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Research on the Change Path of Ordinary High School From the Perspective of Transformational Leadership——Take the No.4 High School of Xi’an High-tech Zone as an Example
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作者 Jianghua Chen 《Journal of Educational Theory and Management》 2024年第4期69-76,共8页
The Guiding Opinions of The General Office of the State Council on Promoting the Reform of ordinary high school education Mode in the New Era directly refers to the reform of ordinary high school education mode,making... The Guiding Opinions of The General Office of the State Council on Promoting the Reform of ordinary high school education Mode in the New Era directly refers to the reform of ordinary high school education mode,making it a new era mission of ordinary high school education development.The reform of ordinary high school is a complex and purposeful event,and the process of reform needs to go through several stages,each stage is faced with unique tasks,contradictions and corresponding strategies of change.As a principal,he must be clear about the goal of the school towards the future,the specific problems he needs to face and the corresponding strategies,and how to promote the overall reform of the school.What is the path of change?The proposal of transformational leadership theory provides a new way of thinking for opening the new situation of school reform.How to learn from the transformational leadership theory to seek an endogenous road for the reform of ordinary high school in our country in the complex contemporary educational environment is an important issue worth educators to study. 展开更多
关键词 Ordinary high school change LEADERSHIP perspective MOTIVATION Care
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Perspective in Development of Shape Memory Materials Associated with Martensitic Transformation 被引量:1
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作者 Zuyao XU (T. Y.Hsu) (Shanghai Jiaotong University, Shanghai, 200030, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1994年第2期107-110,共4页
By consideration of the characteristics of martensitic transformation and the derivation from the application of the group theory to martensitic transformation, it may be concluded that the shape memory effect (SME) c... By consideration of the characteristics of martensitic transformation and the derivation from the application of the group theory to martensitic transformation, it may be concluded that the shape memory effect (SME) can be attained in materials through a martensitic transformation and its reverse transformation. only when there forms single or nearly single variant of martensite, with an absence of the factors causing the generation of the resistance against SME. on this principle, various shape memory materials including nonferrous alloys. iron-based alloys and ceramics containjng zirconia are expected to be further developed. A criterion for thermoelastic martensitic transformation is presented, Factors which may act as the resistance against SME in various materials are briefly described 展开更多
关键词 NI perspective in Development of shape Memory Materials Associated with Martensitic Transformation
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Experimental study on thermal and mechanical properties of tailings-based cemented paste backfill with CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials 被引量:2
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作者 Xiaoyan Zhang Tianrun Cao +3 位作者 Lang Liu Baoyun Bu Yaping Ke Qiangqiang Du 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期250-259,共10页
CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials(CEV)was prepared by atmospheric impregnation method.Using gold mine tailings as aggregate of cemented paste backfill(CPB)material,the ... CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials(CEV)was prepared by atmospheric impregnation method.Using gold mine tailings as aggregate of cemented paste backfill(CPB)material,the CPB with CEV added was prepared,and the specific heat capacity,thermal conductivity,and uniaxial compressive strength(UCS)of CPB with different cement-tailing ratios and CEV addition ratios were tested,the influence of the above variables on the thermal and mechanical properties of CPB was analyzed.The results show that the maximum encapsulation capacity of expanded vermiculite for CaCl_(2)·6H_(2)O is about 60%,and the melting and solidification enthalpies of CEV can reach 98.87 J/g and 97.56 J/g,respectively.For the CPB without CEV,the specific heat capacity,thermal conductivity,and UCS decrease with the decrease of cement-tailing ratio.For the CPB with CEV added,with the increase of CEV addition ratio,the specific heat capacity increases significantly,and the sensible heat storage capacity and latent heat storage capacity can be increased by at least 10.74%and 218.97%respectively after adding 12%CEV.However,the addition of CEV leads to the increase of pores,and the thermal conductivity and UCS both decrease with the increase of CEV addition.When cement-tailing ratio is 1:8 and 6%,9%,and 12%of CEV are added,the 28-days UCS of CPB is less than 1 MPa.Considering the heat storage capacity and cost price of backfill,the recommended proportion scheme of CPB material presents cement-tailing ratio of 1:6 and 12%CEV,and the most recommended heat storage/release temperature cycle range of CPB with added CEV is from 20 to 40℃.This work can provide theoretical basis for the utilization of heat storage backfill in green mines. 展开更多
关键词 CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials cemented paste backfill thermal property mechanical property
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Preparation and Properties of Paraffin/PMMA Shape-stabilized Phase Change Material for Building Thermal Energy Storage 被引量:5
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作者 孟多 ZHAO Kang +1 位作者 WANG Anqi WANG Baomin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第1期231-239,共9页
The composite phase change material(PCM) consisting of phase change paraffin(PCP) and polymethyl methacrylate(PMMA) was prepared as a novel type of shape-stabilized PCM for building energy conservation through the met... The composite phase change material(PCM) consisting of phase change paraffin(PCP) and polymethyl methacrylate(PMMA) was prepared as a novel type of shape-stabilized PCM for building energy conservation through the method of bulk polymerization. The chemical structure, morphology, phase change temperature and enthalpy, and mechanical properties of the composite PCM were studied to evaluate the encapsulation effect of PMMA on PCP and determine the optimal composition proportion. FTIR and SEM results revealed that PCP was physically immobilized in the PMMA so that its leakage from the composite was prevented. Based on the thermo-physical and mechanical properties investigations, the optimal mass fraction of PCP in the composite was determined as 70%. The phase change temperature of the composite was close to that of PCP, and its latent heat was equivalent to the calculated value according to the mass fraction of PCP in the composite. For estimating the usability in practical engineering, thermal stability, reliability and temperature regulation performance of the composite were also researched by TG analysis, thermal cycling treatments and heating-cooling test. The results indicated that PCP/PMMA composite PCM behaved good thermal stability depending on the PMMA protection and its latent heat degraded little after 500 thermal cycling. Temperature regulation performance of the composite before and after thermal cycling was both noticeable due to its latent heat absorption and release in the temperature variation processes. The PCP/PMMA phase change plate was fabricated and applied as thermal insulator in miniature concrete box to estimate its temperature regulation effect under the simulated environmental condition. It can be concluded that this kind of PCP/PMMA shape-stabilized PCM with the advantages of no leakage, suitable phase change temperature and enthalpy, good thermal stability and reliability, and effective temperature regulation performance have much potential for thermal energy storage in building energy conservation. 展开更多
关键词 shape-stabilized PHASE change material PHASE change PARAFFin polymethyl METHACRYLATE temperature regulation BUILDinG energy conservation
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A New Kind of Shape-stabilized Phase Change Materials 被引量:2
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作者 肖力光 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第3期491-494,共4页
Based on the lowest melting point and Schroeder’s theoretical calculation formula,nano- modified organic composite phase change materials(PCMs)were prepared.The phase transition temperature and the latent heat of t... Based on the lowest melting point and Schroeder’s theoretical calculation formula,nano- modified organic composite phase change materials(PCMs)were prepared.The phase transition temperature and the latent heat of the materials were 24℃and 172 J/g,respectively.A new shape-stabilized phase change materials were prepared,using high density polyethylene as supporting material.The PCM kept the shape when temperature was higher than melting point.Thus,it can directly contact with heat transfer media.The structure,morphology and thermal behavior of PCM were analyzed by FTIR,SEM and DSC. 展开更多
关键词 phase change material(PCM) shape-stabilized phase change materials high density polyethylene
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Shaped Insulating Refractory Products——Determination of Permanent Linear Change on Heating
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《China's Refractories》 CAS 2005年第4期38-40,共3页
1 Scope This standard covers the definition, technical requirement, apparatus, specimen, test procedure, calculation and test report on permanent linear change of shaped insulating refractory products.
关键词 Determination of Permanent Linear change on Heating shaped insulating Refractory Products length
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Dense Shaped Refractory Products——Test Method of Linear Changes on Reheating
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《China's Refractories》 CAS 2006年第2期36-38,共3页
This Standard specifies methods for the determination of the linear changes on reheating of a dense shaped refractory product.
关键词 TEST Test Method of Linear changes on Reheating Dense shaped Refractory Products
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Incorporating shape constraints in generalized additive modelling of the height-diameter relationship for Norway spruce 被引量:4
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作者 Natalya Pya Matthias Schmidt 《Forest Ecosystems》 SCIE CSCD 2016年第2期112-125,共14页
Background: Measurements of tree heights and diameters are essential in forest assessment and modelling. Tree heights are used for estimating timber volume, site index and other important variables related to forest ... Background: Measurements of tree heights and diameters are essential in forest assessment and modelling. Tree heights are used for estimating timber volume, site index and other important variables related to forest growth and yield, succession and carbon budget models. However, the diameter at breast height (dbh) can be more accurately obtained and at lower cost, than total tree height. Hence, generalized height-diameter (h-d) models that predict tree height from dbh, age and other covariates are needed. For a more flexible but biologically plausible estimation of covariate effects we use shape constrained generalized additive models as an extension of existing h-d model approaches. We use causal site parameters such as index of aridity to enhance the generality and causality of the models and to enable predictions under projected changeable climatic conditions. Methods: We develop unconstrained generalized additive models (GAM) and shape constrained generalized additive models (SCAM) for investigating the possible effects of tree-specific parameters such as tree age, relative diameter at breast height, and site-specific parameters such as index of aridity and sum of daily mean temperature during vegetation period, on the h-d relationship of forests in Lower Saxony, Germany. Results: Some of the derived effects, e.g. effects of age, index of aridity and sum of daily mean temperature have significantly non-linear pattern. The need for using SCAM results from the fact that some of the model effects show partially implausible patterns especially at the boundaries of data ranges. The derived model predicts monotonically increasing levels of tree height with increasing age and temperature sum and decreasing aridity and social rank of a tree within a stand, The definition of constraints leads only to marginal or minor decline in the model statistics like AIC An observed structured spatial trend in tree height is modelled via 2-dimensional surface fitting. Conclusions: We demonstrate that the SCAM approach allows optimal regression modelling flexibility similar to the standard GAM but with the additional possibility of defining specific constraints for the model effects. The longitudinal character of the model allows for tree height imputation for the current status of forests but also for future tree height prediction. 展开更多
关键词 Height-diameter curve Norway spruce shape constrained additive models Impact of climate change Varying coefficient models
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Selective triggering of phase change in dielectrics by femtosecond pulse trains based on electron dynamics control 被引量:2
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作者 徐传彩 姜澜 +1 位作者 冷妮 刘鹏军 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期334-337,共4页
In this study we experimentally reveal that the phase change mechanism can be selectively triggered by shaping femtosecond pulse trains based on electron dynamics control (EDC), including manipulation of excitations... In this study we experimentally reveal that the phase change mechanism can be selectively triggered by shaping femtosecond pulse trains based on electron dynamics control (EDC), including manipulation of excitations, ionizations, densities, and temperatures of electrons. By designing the pulse energy distribution to adjust the absorptions, excitations, ionizations, and recombinations of electrons, the dominant phase change mechanism experiences transition from nonthermal to thermal process. This phenomenon is observed in quadruple, triple, and double pulses per train ablation of fused silica separately. This opens up possibilities for controlling phase change mechanisms by EDC, which is of great significance in laser processing of dielectrics and fabrication of integrated nano- and micro-optical devices. 展开更多
关键词 phase change electron dynamics pulse shaping
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Effect of different heat transfer fluids on discharging performance of phase change material included cylindrical container during forced convection 被引量:2
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作者 SELİMEFENDİGİL Fatih ŞİRİN Ceylin ÖZTOP Hakan F 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第11期3521-3533,共13页
In the present work,effects of various heat transfer fluids on the discharging performance of a phase change material(PCM) included cylindrical container are numerically assessed during forced convection.The heat tran... In the present work,effects of various heat transfer fluids on the discharging performance of a phase change material(PCM) included cylindrical container are numerically assessed during forced convection.The heat transfer fluid air,hydrogen,water and nanofluid with alumina particles are used and the the geometric variation of the PCM embedded region is also considered.The finite element method is used as the solver.Dynamic features of heat exchange with various phases are explored for different heat transfer fluid types,Reynolds number(between 100 and 300) and PCM embedded region geometric variation(h_(x)between 0.01 d_(1) and 0.65 d_(1),hybetween 0.1 h_(1) and 0.4 h_(1)).It is observed that discharging time is significantly influenced by the heat transfer fluid type while full phase transition time for air is obtained as more than 10 times when hydrogen is utilized as heat transfer fluid.The best performance is achieved with nanofluid.When the PCM integrated region size is reduced,discharging time is generally reduced while due to the form of the geometry,vortex formation is established in the PCM region.This results in performance degeneration at the highest radius and height of the inner cylinder.Discharging time increases by about 12% when radius of the inner cylinder is increased from h_(x)=0.35 d_(1) to h_(x)=0.45 d_(1).Dynamic features of PCM temperature and liquid fraction are affected with Reynolds number while discharging time is reduced by about 48% when configurations with the lowest and highest Reynolds number are compared. 展开更多
关键词 heat transfer fluid HYDROGEN phase change material finite element method container shape
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Effect of Selective Medicinal Plant Extract on Blood Glucose, Sperm Shape and Various Physiological Parameters 被引量:1
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作者 Salla Hemadri Reddy Ibtisam Saif Al-Neeri +1 位作者 Hadeel Khalifa Al-Issaei Sara Mohammed Al-Jabri 《American Journal of Plant Sciences》 2015年第8期1109-1115,共7页
Salvadora persica, Moringa pergrina and Citrullus colocynthis are three traditional important medicinal species used in indigenous medicinal herbal drugs to cure various diseases in South Asia and Middle East countrie... Salvadora persica, Moringa pergrina and Citrullus colocynthis are three traditional important medicinal species used in indigenous medicinal herbal drugs to cure various diseases in South Asia and Middle East countries. The objective of the present study is to investigate the effects of oral administration of extracts of Salvadora persica leaves, Moringa pergrina leaves and Citrullus colocynthis seeds on different physiological parameters of mice. The leaves of Salvadora persica, Moringa pergrina and Citrullus colocynthis seeds were collected from Ibri and Al-Musanaa, dried and crushed into powder and extract was obtained by soxhalet apparatus. The extract was then administered to mice at a dosage of 0.5%, 1.0%, 1.5% and 2.0% for twenty one days. The mice treated with different concentrations of plant extracts showed different physiological changes, Salvadora persica leaf extract at 1.5% and 2.0% showed hypo activity, grooming, prostration, while mice treated with 0.5% and 1.0% showed no effective behavioral changes. The Moringa pergrina leaf extract dosage of 0.5%, 1.0%, 1.5% and 2.0% produced significant weight loss and affected the blood sugar level. Citrullus colocynthis seed extract at 1.5% and 2.0% showed abnormal sperms shape like circular head, double head and double tails whereas at 0.5% and 1.0% exhibited normal sperm shape. 展开更多
关键词 PHYTOCHEMICAL Screening Blood SUGAR Level SPERM shape PHYSIOLOGICAL changes
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Shape Similarity Measures of Linear Entities 被引量:1
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作者 ZhangQiaopin LIDeren 《Geo-Spatial Information Science》 2002年第2期62-67,共6页
The essential of feature matching technology lies in how to measure the similarity of spatial entities.Among all the possible similarity measures,the shape similarity measure is one of the most important measures beca... The essential of feature matching technology lies in how to measure the similarity of spatial entities.Among all the possible similarity measures,the shape similarity measure is one of the most important measures because it is easy to collect the necessary parameters and it is also well matched with the human intuition.In this paper a new shape similarity measure of linear entities based on the differences of direction change along each line is presented and its effectiveness is illustrated. 展开更多
关键词 feature matching similarity measures of spatial entities shape analysis differences of direction change
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Melting Intercalation Method to Prepare Lauric Acid/Organophilic Montmorillonite Shape-stabilized Phase Change Material 被引量:3
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作者 陈美祝 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第4期674-677,共4页
A kind of novel shape-stabilized phase change material (SSPCM) was prepared by using a melting intercalation technique. This kind of SSPCM was made of lauric acid (LA) as a phase change material and organophilic m... A kind of novel shape-stabilized phase change material (SSPCM) was prepared by using a melting intercalation technique. This kind of SSPCM was made of lauric acid (LA) as a phase change material and organophilic montmorillonite (OMMT) as a support material. And the thermal properties and morphology of the SSPCM were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electronic microscope (SEM), scanning calorimeter (DSC), and differential thermal cravimetry (TG). The DSC result shows that the phase change temperature of the SSPCM is close to that of LA, and its latent heat is equivalent to that of the calculated value based on the mass ratio of LA measured by TG. The XRD, SEM and TEM results demonstrate that the LA intercalates into the silicate layers of the OMMT, thus forming a typically intercalted hybrid, which can restrict the molecular chain of the LA within the structure of OMMT at high temperature. And consequently SSPCM can keep its solid state during its solid-liquid phase change processing. 展开更多
关键词 shape-stabilized phase change material lauric acid organophilic montmorillonite melting intercalation
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Preface to the Special Issue “Unified Perspective of Climate Variability and Change”
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作者 Shang-Ping XIE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第4期409-410,共2页
Forty years ago, Klaus Wyrtki (1975) of University of Hawaii discovered that E1 Nifio warming off South America is not a result of local wind change but a response to the relaxed equatorial trade winds some 10 000 k... Forty years ago, Klaus Wyrtki (1975) of University of Hawaii discovered that E1 Nifio warming off South America is not a result of local wind change but a response to the relaxed equatorial trade winds some 10 000 km away near the international dateline. The Kelvin wave mechanism was quickly verified from wind-forced ocean model simulations. Consequent develop- ments show that the dance between the fast-reacting atmosphere and slow-evolving ocean sets the pace of E1 Nifio-Southern Oscillation (ENSO; Philander, 1990). The concept of ocean-atmosphere interaction has revolutionized our view of the climate system and led to operational climate prediction. 展开更多
关键词 Preface to the Special Issue Unified perspective of Climate Variability and change ENSO
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APPROXIMATION AND SHAPE-PRESERVING PROPERTIES OF Q-STANCU OPERATOR
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作者 Lianying Yun Rongwei Wang 《Analysis in Theory and Applications》 2011年第3期201-210,共10页
We introduce the definition of q-Stancu operator and investigate its approximation and shape-preserving property. With the help of the sign changes of f(x) and Ln = f(f, q;x) the shape-preserving property of q-Sta... We introduce the definition of q-Stancu operator and investigate its approximation and shape-preserving property. With the help of the sign changes of f(x) and Ln = f(f, q;x) the shape-preserving property of q-Stancu operator is obtained. 展开更多
关键词 q-Stancu operator shape-preserving property sign change
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Modeling method and preliminary model of Asteroid Toutatis from Chang'E-2 optical images 被引量:1
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作者 Xiang-Yu Li Dong Qiao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第3期310-315,共6页
Shape modeling is fundamental to the analysis of dynamic environment and motion around asteroid. Chang'E- 2 successfully made a flyby of Asteroid 4179 Toutatis and obtained plenty of high-resolution images during the... Shape modeling is fundamental to the analysis of dynamic environment and motion around asteroid. Chang'E- 2 successfully made a flyby of Asteroid 4179 Toutatis and obtained plenty of high-resolution images during the mis- sion. In this paper, the modeling method and preliminary model of Asteroid Toutatis are discussed. First, the optical images obtained by Chang'E-2 are analyzed. Terrain and silhouette features in images are described. Then, the modeling method based on previous radar model and preliminary information from optical images is proposed. A preliminary polyhedron model of Asteroid Toutatis is established. Finally, the spherical harmonic coefficients of Asteroid Toutatis based on the polyhedron model are obtained. Some parameters of model are analyzed and compared. Although the model proposed in this paper is only a preliminary model, this work offers a valuable reference for future high-resolution models. 展开更多
关键词 Chang'E-2 Asteroid Toutatis shape modeling.Polyhedron method
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Applying Humboldt’s holistic perspective in China’s sustainability 被引量:1
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作者 Jian-Guo Gao 《Geography and Sustainability》 2021年第2期123-126,共4页
Alexander von Humboldt,was a great German geobotanist,educator and naturalist who greatly influenced sci-ence and humanities for more than two hundred years.In addition to scientific contributions(such as the un-derst... Alexander von Humboldt,was a great German geobotanist,educator and naturalist who greatly influenced sci-ence and humanities for more than two hundred years.In addition to scientific contributions(such as the un-derstanding of vegetation distribution,the concepts of isotherm and pressure contours,and the initial concept of continental drift theory),he firmly believed in the concept of the interconnection of everything and the method-ological approach of a holistic perspective to development,which has significance in achieving the UN Sustainable Development Goals,because they include both synergy and trade-offs among these goals.China has undergone tremendous changes since its reform and opening up in 1978 and now faces severe challenges in sustainable de-velopment.The scientific methods applied by Chinese scientists in sustainability fulfil the Humboldtian holistic perspective of nature.Here I provide four successful cases and their significant implications for addressing the increasingly severe water shortage,biological conservation,and conflicts between human well-being and land.The four examples discussed in this article are enlightened to establish a strong,just,and influential government and require empirical research to implement sustainable development plans.I believe that it’s vital to encourage and supervise public participation for a successful program;for example,the participants should not be restricted to project executors,i.e.,farmers or workers,but also students and scientists.Eradicating poverty must be priori-tized,and well-being is the ultimate goal for sustainable development.This review article provides an extremely valuable reference for other developing or even developed countries to address sustainability challenges. 展开更多
关键词 Biological conservation Climate change Energy Food security Holistic perspective Water resource Sustainable development goals
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Spatio-Temporal Kinematic Decomposition of Movements 被引量:1
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作者 Dimitri Volchenkov Bettina E.Blasing Thomas Schack 《Engineering(科研)》 2014年第8期385-398,共14页
We propose the new experimental method for investigating and approximating the organization and structure of movements with given accuracy. The composition of approximating trajectories illuminating the movement trait... We propose the new experimental method for investigating and approximating the organization and structure of movements with given accuracy. The composition of approximating trajectories illuminating the movement traits discloses the level of movement expertise in dancers and golf players. The method allows estimating the level of movement expertise, drawing the detailed structure of movements, and classifying movements into a given repertoire automatically. 展开更多
关键词 Kinematic Structure of Movements Spatio-Temporal Kinematic Decomposition of Movement Complexity of Movements Complexity of shape changes Automated Classification of Movements
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Phase transition characteristics of the Ni_(46)Mn_(35)Ga_(19) single crystal
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作者 CUI Yuting LI Li 《商丘师范学院学报》 CAS 2010年第6期50-54,共5页
The phase transition characteristics of the prepared Ni46Mn35Ga19 single crystal have been systematically investigated by measuring resistance,strain,heat flow,and ac magnetic susceptibility.The experimental results i... The phase transition characteristics of the prepared Ni46Mn35Ga19 single crystal have been systematically investigated by measuring resistance,strain,heat flow,and ac magnetic susceptibility.The experimental results indicate that both magnetic transition and martensitic transformation occurred simultaneously and the corresponding transition temperature was about 356 K.Meanwhile,the prepared single crystal also exhibited spontaneous and magnetic-field-enhanced two-way thermal shape memory effect with the strains up to-0.89% and-1.90% with and without a magnetic field of 1.6 T,respectively.The possible mechanism of the large spontaneous and magnetic enhanced deformation were analyzed based on the phase transition characteristics of Ni46Mn35Ga19 single crystal and the preferential orientation of martensitic variants. 展开更多
关键词 D.Magnetic entropy change D.shape memory effect C.Martensitic transformation D.Magnetic transition
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主动变位索网结构体系索力识别方法及FAST工程应用
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作者 付兴 孙思源 +3 位作者 李宏男 李庆伟 李辉 任亮 《振动工程学报》 北大核心 2025年第1期135-143,共9页
为准确识别FAST索网结构体系的拉索索力,本文提出了一种可变弹性边界支承的拉索索力识别方法。建立了拉索等效单自由度模型,推导了理想铰接与弹性边界支承下拉索频率间的数学表达式,通过拉索中点、两端点的第一阶振型值对第一阶频率进... 为准确识别FAST索网结构体系的拉索索力,本文提出了一种可变弹性边界支承的拉索索力识别方法。建立了拉索等效单自由度模型,推导了理想铰接与弹性边界支承下拉索频率间的数学表达式,通过拉索中点、两端点的第一阶振型值对第一阶频率进行修正,进而提出了基于弦振动理论的主动变位索网结构体系索力识别方法;对单根拉索开展数值仿真,验证了所提方法的准确性,并开展了参数分析;通过数值仿真及现场实测对FAST索网结构进行索力识别,证明了方法的可行性和工程适用性。结果表明:数值仿真的索力识别相对误差在1%以内,现场实测的索力识别相对误差小于5%。该方法考虑了拉索的复杂边界条件,可避免求解未知边界约束刚度,拓展了传统弦振动理论的工程适用性。 展开更多
关键词 主动变位索网结构体系 可变弹性边界支承 等效单自由度体系 索力识别 频率修正
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