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Timing theory integrated nursing combined behavior change integrated theory of nursing on primiparous influence
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作者 Yan-Xia He Yang Lv +2 位作者 Ting-Ting Lan Fang Deng Yuan-Yuan Zhang 《World Journal of Clinical Cases》 SCIE 2024年第2期293-301,共9页
BACKGROUND The comprehension and utilization of timing theory and behavior change can offer a more extensive and individualized provision of support and treatment alternatives for primipara.This has the potential to e... BACKGROUND The comprehension and utilization of timing theory and behavior change can offer a more extensive and individualized provision of support and treatment alternatives for primipara.This has the potential to enhance the psychological well-being and overall quality of life for primipara,while also furnishing healthcare providers with efficacious interventions to tackle the psychological and physiological obstacles encountered during the stages of pregnancy and postpartum.AIM To explore the effect of timing theory combined with behavior change on selfefficacy,negative emotions and quality of life in patients with primipara.METHODS A total of 80 primipara cases were selected and admitted to our hospital between August 2020 and May 2022.These cases were divided into two groups,namely the observation group and the control group,with 40 cases in each group.The nursing interventions differed between the two groups,with the control group receiving routine nursing and the observation group receiving integrated nursing based on the timing theory and behavior change.The study aimed to compare the pre-and post-nursing scores of Chinese Perceived Stress Scale(CPSS),Edinburgh Postpartum Depression Scale(EPDS),Self-rating Anxiety Scale(SAS),breast milk knowledge,self-efficacy,and SF-36 quality of life in both groups.RESULTS After nursing,the CPSS,EPDS,and SAS scores of the two groups was significantly lower than that before nursing,and the CPSS,EPDS,and SAS scores of the observation group was significantly lower than that of the control group(P=0.002,P=0.011,and P=0.001 respectively).After nursing,the breastfeeding knowledge mastery,selfefficacy,and SF-36 quality of life scores was significantly higher than that before nursing,and the breastfeeding knowledge mastery(P=0.013),self-efficacy(P=0.008),and SF-36 quality of life(P=0.011)scores of the observation group was significantly higher than that of the control group.CONCLUSION The integration of timing theory and behavior change integrated theory has been found to be an effective approach in alleviating negative mood and stress experienced by primipara individuals,while also enhancing their selfefficacy and overall quality of life.This study focuses on the key concepts of timing theory,behavior change,primipara individuals,negative mood,and quality of life. 展开更多
关键词 Timing theory Behavior change PRIMIPARA Bad mood Quality of life
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Challenges and Countermeasures for Integrating the Protection of Environmental Rights into Actions for Addressing Climate Change
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作者 秦天宝 袁野阳光 《The Journal of Human Rights》 2023年第4期869-893,共25页
Climate change,which is the result of human activities,has wide-ranging impact.It poses a serious threat to human rights.Environmental rights are where the protection of the ecological environment and the development ... Climate change,which is the result of human activities,has wide-ranging impact.It poses a serious threat to human rights.Environmental rights are where the protection of the ecological environment and the development of human rights intersect.In view of the close relationship between the actions for addressing climate change and environmental rights,China should integrate the protection of environmental rights into the actions for addressing climate change,so as to achieve simultaneous development of both.In the process of coping with climate change,the right to climate stability that mainly pursues a“harmless”environment and the right to a more livable climate that pursues a“beautiful eco-environment”are specific manifestations of environmental rights and should be the priority of protection efforts.However,there are still some obstacles to achieving the coordinated development of the efforts to address climate change and the protection of environmental rights because traditional rights protection methods mainly give individuals subjective rights with the power to claim and are thus difficult to meet the needs of environmental rights protection in the context of climate change,and there are inherent value differences between responding to climate change and the realization of other human rights.Building a multi-level national obligation system to address climate change,giving full play to the role of courts in responding to climate change through moderate judicial activism,and coordinating the efforts to cope with climate change and the development of human rights under the guidance of a holistic system view are effective ways to overcome the aforementioned difficulties. 展开更多
关键词 actions for addressing climate change environmental rights judicial activism holistic system view
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Runoff change in the Yellow River Basin of China from 1960 to 2020 and its driving factors
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作者 WANG Baoliang WANG Hongxiang +3 位作者 JIAO Xuyang HUANG Lintong CHEN Hao GUO Wenxian 《Journal of Arid Land》 SCIE CSCD 2024年第2期168-194,共27页
Analysing runoff changes and how these are affected by climate change and human activities is deemed crucial to elucidate the ecological and hydrological response mechanisms of rivers.The Indicators of Hydrologic Alte... Analysing runoff changes and how these are affected by climate change and human activities is deemed crucial to elucidate the ecological and hydrological response mechanisms of rivers.The Indicators of Hydrologic Alteration and the Range of Variability Approach(IHA-RVA)method,as well as the ecological indicator method,were employed to quantitatively assess the degree of hydrologic change and ecological response processes in the Yellow River Basin from 1960 to 2020.Using Budyko's water heat coupling balance theory,the relative contributions of various driving factors(such as precipitation,potential evapotranspiration,and underlying surface)to runoff changes in the Yellow River Basin were quantitatively evaluated.The results show that the annual average runoff and precipitation in the Yellow River Basin had a downwards trend,whereas the potential evapotranspiration exhibited an upwards trend from 1960 to 2020.In approximately 1985,it was reported that the hydrological regime of the main stream underwent an abrupt change.The degree of hydrological change was observed to gradually increase from upstream to downstream,with a range of 34.00%-54.00%,all of which are moderate changes.However,significant differences have been noted among different ecological indicators,with a fluctuation index of 90.00%at the outlet of downstream hydrological stations,reaching a high level of change.After the mutation,the biodiversity index of flow in the middle and lower reaches of the Yellow River was generally lower than that in the base period.The research results also indicate that the driving factor for runoff changes in the upper reach of the Yellow River Basin is mainly precipitation,with a contribution rate of 39.31%-54.70%.Moreover,the driving factor for runoff changes in the middle and lower reaches is mainly human activities,having a contribution rate of 63.70%-84.37%.These results can serve as a basis to strengthen the protection and restoration efforts in the Yellow River Basin and further promote the rational development and use of water resources in the Yellow River. 展开更多
关键词 Budyko theory hydrological regime attribution analysis ecological responses Yellow River climate change human activity RUNofF
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Impacts of multi-scenario land use change on ecosystem services and ecological security pattern: A case study of the Yellow River Delta
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作者 XueHua Cen Hua Zhang 《Research in Cold and Arid Regions》 CSCD 2024年第1期30-44,共15页
The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the regio... The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the region has witnessed significant land use/cover changes(LUCC), impacting ecosystem services(ES) and ecological security patterns(ESP). Investigating LUCC's effects on ES and ESP in the YRD is crucial for ecological security and sustainable development. This study utilized the PLUS model to simulate 2030 land use scenarios, including natural development(NDS), economic development(EDS), and ecological protection scenarios(EPS). Subsequently, the InVEST model and circuit theory were applied to assess ES and ESP under varying LUCC scenarios from 2010 to 2030. Findings indicate:(1) Notable LUCC from 2010 to 2030, marked by decreasing cropland and increasing construction land and water bodies.(2) From 2010 to 2020, improvements were observed in carbon storage,water yield, soil retention, and habitat quality, whereas 2020–2030 saw increases in water yield and soil retention but declines in habitat quality and carbon storage. Among the scenarios, EPS showed superior performance in all four ES.(3) Between 2010 and 2030, ecological sources, corridors, and pinchpoints expanded, displaying significant spatial heterogeneity. The EPS scenario yielded the most substantial increases in ecological sources,corridors, and pinchpoints, totaling 582.89 km^(2), 645.03 km^(2),and 64.43 km^(2), respectively. This study highlights the importance of EPS, offering insightful scientific guidance for the YRD's sustainable development. 展开更多
关键词 Land use change Multi-scenario simulation Ecosystem services Ecological security pattern the Yellow River Delta Circuit theory
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Quantitative distinction of the relative actions of climate change and human activities on vegetation evolution in the Yellow River Basin of China during 1981-2019 被引量:4
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作者 LIU Yifeng GUO Bing +3 位作者 LU Miao ZANG Wenqian YU Tao CHEN Donghua 《Journal of Arid Land》 SCIE CSCD 2023年第1期91-108,共18页
Under the combined influence of climate change and human activities,vegetation ecosystem has undergone profound changes.It can be seen that there are obvious differences in the evolution patterns and driving mechanism... Under the combined influence of climate change and human activities,vegetation ecosystem has undergone profound changes.It can be seen that there are obvious differences in the evolution patterns and driving mechanisms of vegetation ecosystem in different historical periods.Therefore,it is urgent to identify and reveal the dominant factors and their contribution rates in the vegetation change cycle.Based on the data of climate elements(sunshine hours,precipitation and temperature),human activities(population intensity and GDP intensity)and other natural factors(altitude,slope and aspect),this study explored the spatial and temporal evolution patterns of vegetation NDVI in the Yellow River Basin of China from 1989 to 2019 through a residual method,a trend analysis,and a gravity center model,and quantitatively distinguished the relative actions of climate change and human activities on vegetation evolution based on Geodetector model.The results showed that the spatial distribution of vegetation NDVI in the Yellow River Basin showed a decreasing trend from southeast to northwest.During 1981-2019,the temporal variation of vegetation NDVI showed an overall increasing trend.The gravity centers of average vegetation NDVI during the study period was distributed in Zhenyuan County,Gansu Province,and the center moved northeastwards from 1981 to 2019.During 1981-2000 and 2001-2019,the proportion of vegetation restoration areas promoted by the combined action of climate change and human activities was the largest.During the study period(1981-2019),the dominant factors influencing vegetation NDVI shifted from natural factors to human activities.These results could provide decision support for the protection and restoration of vegetation ecosystem in the Yellow River Basin. 展开更多
关键词 vegetation evolution driving mechanisms climate change human activities relative actions Geodetector Yellow River Basin
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The action mechanisms and structures designs of F-containing functional materials for high performance oxygen electrocatalysis 被引量:1
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作者 Gang Wang Shuwei Jia +7 位作者 Hongjing Gao Yewen Shui Jie Fan Yixia Zhao Lei Li Weimin Kang Nanping Deng Bowen Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期377-397,I0010,共22页
Non-renewable fossil fuels have led to serious problems such as global warming,environmental pollution,etc.Oxygen electrocatalysis including oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)plays a cent... Non-renewable fossil fuels have led to serious problems such as global warming,environmental pollution,etc.Oxygen electrocatalysis including oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)plays a central role in clean energy conversion,enabling a number of sustainable processes for future air battery technologies.Fluorine,as the most electronegative element(4.0)not only can induce more efficient regulation for the electronic structure,but also can bring more abundant defects and other novel effects in materials selection and preparation for favorable catalysis with respect to the other nonmetal elements.However,an individual and comprehensive overview of fluorine-containing functional materials for oxygen electrocatalysis field is still blank.Therefore,it is very meaningful to review the recent progresses of fluorine-containing oxygen electrocatalysts.In this review,we first systematically summarize the controllable preparation methods and their possible development directions based on fluorine-containing materials from four preparation methods.Due to the strong electron-withdrawing properties of fluorine,its control of the electronic structure can effectively enhance the oxygen electrocatalytic activity of the materials.In addition,the catalytic enhancement effect of fluorine on carbonbased materials also includes the prevent oxidation and the layer peeling,and realizes the precise atomic control.And the catalytic improvement mechanism of fluorine containing metal-based compounds also includes the hydration of metal site,the crystal transformation,and the oxygen vacancy induction.Then,based on their various dimensions(0D–3D),we also have summarized the advantages of different morphologies on oxygen electrocatalytic performances.Finally,the prospects and possible future researching direction of F-containing oxygen electrocatalysts are presented(e.g.,novel pathways,advanced methods for measurement and simulation,field assistance and multi-functions).The review is considered valuable and helpful in exploring the novel designs and mechanism analyses of advanced fluorine-containing electrocatalysts. 展开更多
关键词 Fluorine-containing functional materials action mechanisms and structure designs Density functional theory Oxygen evolution reaction Oxygen reduction reaction
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Understanding the Underlying Mechanisms of Action for Successful Implementation of Social Prescribing
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作者 Kate Walker Chris Griffiths Harmony Jiang 《Open Journal of Preventive Medicine》 CAS 2023年第2期41-56,共16页
There is growing evidence for the use of social prescribing as a means of facilitating healthy lifestyle behavior changes by linking patients to sources of support in the community. However, there are gaps in understa... There is growing evidence for the use of social prescribing as a means of facilitating healthy lifestyle behavior changes by linking patients to sources of support in the community. However, there are gaps in understanding about what works to facilitate and enable this behavior change i.e. , the mechanisms of actions underpinning social prescribing delivery. This study used a qualitative approach involving interviews with 18 Social Prescription Link Workers (SPLWs). Reflective thematic analysis was used to analyze the data. Through this, an overall theme of “Theoretical underpinning: Solution-focused and strengths-based” was identified. This was made up of sub-themes relating to mechanisms underpinning: the SPLWs’ role (comprising asking questions, motivational interviewing and the therapeutic alliance);the patients’ role, (empowerment and active engagement);and the approach adopted (solution building, goal and action orientated). To formalize this, a framework could be developed for SPLWs that encapsulates the solution-focused strengths-based approach for application within social prescribing. This framework can then be embedded into practice facilitating more successful healthy lifestyle behavior change for social prescribing patients. 展开更多
关键词 Social Prescribing Behaviour change SOLUTION-FOCUSED Goal and action Orientation
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Globalization Under the Spells of Breakdowns in Supply Chains, Regime Change, Regime Formation, and Alliance Restructuring: How Much Is Left for Public Goods?
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作者 Ekkart Zimmermann 《International Relations and Diplomacy》 2023年第5期211-216,共6页
In a paper conceived about five years ago(“Globalization and Public Goods:Too Big to Tackle?”)roughly a dozen factors were linked to explain important causal paths from globalization to the potential output of publi... In a paper conceived about five years ago(“Globalization and Public Goods:Too Big to Tackle?”)roughly a dozen factors were linked to explain important causal paths from globalization to the potential output of public goods.The Russian invasion of Ukraine,the corona epidemic,and the increased hegemonic rivalry between China and the U.S.interrupted or even destroyed many of the linkages between globalization and potential public good production.About five important detrimental paths involved in the meantime.In the present article we aim at linking what is left from the previous level of globalization or emerging to form a new and simplified causal model for likely linkages between truncated or(re-)emerging globalization,and the deadly needed output of public goods.These linkages refer to rules of climate control,go to trade linkages and arbitrary tariffs and trade interventions.Regime change,regime formation,and alliance restructuring address aspects of domestic rule and international stability.Selectorate theory,regime type,and exit options for political elites provide key explanatory factors in explaining globalization and public goods productions,or their decay.Where possible we use some data and transformation experiences corroborating our arguments.In other instances need for further empirical macro research will become clear. 展开更多
关键词 hegemonic rivalry new alliances and bloc formation de-globalization and re-globalization selectorate theory regime type and regime change elite exit options public goods
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Analysis of the USD/JPY and EUR/JPY Exchange Rates Using Multifractal Analysis and Extreme Value Theory
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作者 Fumio Maruyama 《Journal of Applied Mathematics and Physics》 2023年第10期2816-2827,共12页
We performed a multifractal analysis using wavelet transform to detect the changes in the fractality of the USD/JPY and EUR/JPY exchange rates, and predicted their extreme values using extreme value theory. After the ... We performed a multifractal analysis using wavelet transform to detect the changes in the fractality of the USD/JPY and EUR/JPY exchange rates, and predicted their extreme values using extreme value theory. After the 1997 Asian financial crisis, the USD/JPY and EUR/JPY became multifractal, then the USD/JPY became monofractal and stable, and yen depreciation was observed. However, the EUR/JPY became multifractal and unstable, and a strong yen depreciation was observed. The coherence between the USD/JPY and EUR/JPY was strong between 1995 and 2000. After the 2007-2008 financial crisis, the USD/JPY became monofractal and stable, and yen appreciation was observed. However, the EUR/JPY became multifractal and unstable, and strong yen appreciation was observed. Various diagnostic plots for assessing the accuracy of the GP model fitted to USD/JPY and EUR/JPY are shown, and all the diagnostic plots support the fitted GP model. The shape parameters of USD/JPY and EUR/JPY were close to zero, therefore the USD/JPY and EUR/JPY did not have finite upper limits. We predicted the maximum return level for the return periods of 10, 20, 50, 100, 350, and 500 years and their respective 95% confidence intervals (CI). As a result, the 10-year and 100-year return levels for USD/JPY were estimated to be 149.6 and 164.8, with 95% CI [143.2, 156.0] and [149.4, 180.1], respectively. 展开更多
关键词 WAVELET MULTIFRACTAL Extreme Value theory GP USD/JPY and EUR/JPY Ex-change Rates
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Monitoring the change in horizontal stress with multi-wave time-lapse seismic response based on nonlinear elasticity theory 被引量:2
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作者 Fu-Bin Chen Zhao-Yun Zong Xing-Yao Yin 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期815-826,共12页
Monitoring the change in horizontal stress from the geophysical data is a tough challenge, and it has a crucial impact on broad practical scenarios which involve reservoir exploration and development, carbon dioxide (... Monitoring the change in horizontal stress from the geophysical data is a tough challenge, and it has a crucial impact on broad practical scenarios which involve reservoir exploration and development, carbon dioxide (CO_(2)) injection and storage, shallow surface prospecting and deep-earth structure description. The change in in-situ stress induced by hydrocarbon production and localized tectonic movements causes the changes in rock mechanic properties (e.g. wave velocities, density and anisotropy) and further causes the changes in seismic amplitudes, phases and travel times. In this study, the nonlinear elasticity theory that regards the rock skeleton (solid phase) and pore fluid as an effective whole is used to characterize the effect of horizontal principal stress on rock overall elastic properties and the stress-dependent anisotropy parameters are therefore formulated. Then the approximate P-wave, SV-wave and SH-wave angle-dependent reflection coefficient equations for the horizontal-stress-induced anisotropic media are proposed. It is shown that, on the different reflectors, the stress-induced relative changes in reflectivities (i.e., relative difference) of elastic parameters (i.e., P- and S-wave velocities and density) are much less than the changes in contrasts of anisotropy parameters. Therefore, the effects of stress change on the reflectivities of three elastic parameters are reasonably neglected to further propose an AVO inversion approach incorporating P-, SH- and SV-wave information to estimate the change in horizontal principal stress from the corresponding time-lapse seismic data. Compared with the existing methods, our method eliminates the need for man-made rock-physical or fitting parameters, providing more stable predictive power. 1D test illustrates that the estimated result from time-lapse P-wave reflection data shows the most reasonable agreement with the real model, while the estimated result from SH-wave reflection data shows the largest bias. 2D test illustrates the feasibility of the proposed inversion method for estimating the change in horizontal stress from P-wave time-lapse seismic data. 展开更多
关键词 Monitoring change in horizontal stress Multi-wave reflection coefficients Nonlinear elasticity theory Time-lapse seismic data
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The Pursuit of Fallacy in Density Functional Theory: The Quest for Exchange and Correlation, the Rigorous Treatment of Exchange in the Kohn-Sham Formalism and the Continuing Search for Correlation
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作者 A. Gonis 《World Journal of Condensed Matter Physics》 2014年第3期200-225,共26页
As pointed out in the paper preceding this one, in the case of functionals whose independent variable must obey conditions of integral normalization, conventional functional differentiation, defined in terms of an arb... As pointed out in the paper preceding this one, in the case of functionals whose independent variable must obey conditions of integral normalization, conventional functional differentiation, defined in terms of an arbitrary test function, is generally inapplicable and functional derivatives with respect to the density must be evaluated through the alternative and widely used limiting procedure based on the Dirac delta function. This leads to the determination of the rate of change of the dependent variable with respect to its independent variable at each isolated pair, , that may not be part of a functional (a set of ordered pairs). This extends the concept of functional derivative to expectation values of operators with respect to wave functions leading to a density even if the wave functions (and expectation values) do not form functionals. This new formulation of functional differentiation forms the basis for the study of the mathematical integrity of a number of concepts in density functional theory (DFT) such as the existence of a universal functional of the density, of orbital-free density functional theory, the derivative discontinuity of the exchange and correlation functional and the extension of DFT to open systems characterized by densities with fractional normalization. It is shown that no universal functional exists but, rather, a universal process based only on the density and independent of the possible existence of a potential, leads to unique functionals of the density determined through the minimization procedure of the constrained search. The mathematical integrity of two methodologies proposed for the treatment of the Coulomb interaction, the self-interaction free method and the optimized effective potential method is examined and the methodologies are compared in terms of numerical calculations. As emerges from this analysis, the optimized effective potential method is found to be numerically approximate but formally invalid, contrary to the rigorously exact results of the self-interaction-free method. 展开更多
关键词 DENSITY FUNCTIONAL theory Variational Properties of DENSITY FUNCTIONAL theory Self-Interaction Error Optimized Effective Potential FUNCTIONAL DERIVATIVE Parametric DERIVATIVE FUNCTIONAL Rate of change DERIVATIVE Discontinuity Orbital-Free DENSITY FUNCTIONAL theory EXchange and CORRELATION FUNCTIONAL
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Research on the construction path of the megacity from the perspective of Nudge Theory:Empirical evidence of the“Park City”construction in Chengdu Tianfu New Area
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作者 Xiaoqin Xie Xinglong Gong Shaojie Pan 《Chinese Journal of Population,Resources and Environment》 2023年第3期163-171,共9页
The transformation of Chengdu Tianfu New Area,a state-level new district,from the first site of constructing the“Park City”to the representative of the“Park City”,contains a unique path of“Chinese Style Governanc... The transformation of Chengdu Tianfu New Area,a state-level new district,from the first site of constructing the“Park City”to the representative of the“Park City”,contains a unique path of“Chinese Style Governance”.To expand the diverse paths of constructing megacities,the current research references the nudge theory of behavioral science,adopts the extended case method,and takes Chengdu Tianfu New Area as a typical case to summarize the“nudge”path of“Party City”construction.The study found that the government achieves the lock-in effect by the priming mechanism and uses the nudge strategy of improving environment and guiding public opinion,thereby helping the people make free choices.It realizes the framework effect by the salience mechanism and uses the strategies of highlighting key information and optimizing information delivery methods,which directly affects the behavior of the public.It achieves the commitment effect by the comparison mechanism,including the horizontal comparison and vertical comparison strategies,and gradually realizes the policy goals.It realizes the social norm effect by the imitation mechanism and uses the strategies of creating peer pressure and playing celebrity effect,which in turn influence people’s choices.With the help of the“nudging”mechanism,the construction of the park city has realized the interactive cycle of“government output-citizen feedback”and achieved the goal of“making great change through small actions”.As a new behavioral intervention tool,“nudging”provides an alternative explanation for the construction of the park city in Tianfu New Area and opens up new ideas for the construction of megacities.This study concludes that the construction of megacities can achieve the goal of“common return”through different ways and provides practical inspiration for future urban construction. 展开更多
关键词 Behavior nudge MEGACITIES Common return through different ways Making great change through small actions
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College English Teaching Study Conducted by Discovery Learning Theory and Action Research——Take College English Ⅱ for Instance
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作者 李姝颖 《海外英语》 2017年第4期221-222,共2页
The unceasing revolution of the global economy and culture boosts the revolutionary step of the educational circle.Combining the creed of The Guide of College English Teaching in 2016 with the results of investigation... The unceasing revolution of the global economy and culture boosts the revolutionary step of the educational circle.Combining the creed of The Guide of College English Teaching in 2016 with the results of investigation and survey in colleges, a research group in the Institute of Foreign Languages of Hankou University comes up with a revolutionary trial scheme on College English teaching conducted by discovery learning theory, as well as a research method of action research, which is in hope of mending the problems and shortcomings of current College English teaching. 展开更多
关键词 college English discovery learning theory action research teaching revolution
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APPLICABILITY OF THE MASS ACTION LAW IN COMBINATION WITH THE COEXISTENCE THEORY OF METALLIC MELTS INVOLVING COMPOUND TO BINARY METALLIC MELTS 被引量:4
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作者 J.ZhangMetallurgical Engineering School, University of Science and Technology Beijing, Beijing 100083, China Manuscript received 9 March 2001 in revised form 7 August 2001 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2002年第4期353-362,共10页
Based on the atomicity and molecularity as well as the consistency ofthermodynamic properties and activities of metallic melts with their structures, the coexistencetheory of metallic melts structure involving compoun... Based on the atomicity and molecularity as well as the consistency ofthermodynamic properties and activities of metallic melts with their structures, the coexistencetheory of metallic melts structure involving compound has been suggested. According to this theory,the calculating models of mass action concentrations for different binary metallic melts have beenformulated. The calculated mass action concentrations agree well with corresponding measuredactivities, which confirms that the suggested theory can reflect the structural characteristics ofmetallic melts involving compound and that the mass action law is widely applicable to this kind ofmetallic melts. 展开更多
关键词 metallic melts activity mass action law coexistence theory
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Calculating Models of Mass Action Concentrations for Fe-P and Cr-P Melts and Optimization of Their Thermodynamic Parameters 被引量:2
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作者 Jian Zhang(Metallurgy School, University of Science and Technology Beijing, Beijing 100083, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1999年第3期174-177,共4页
Based on the phase diagrams, reliable reference experimental data and the coexistence theory of metallic melts structure involving compound formation, calculating models of mass action concentrations for Fe-P and Cr-... Based on the phase diagrams, reliable reference experimental data and the coexistence theory of metallic melts structure involving compound formation, calculating models of mass action concentrations for Fe-P and Cr-P melts have been formulated. At the same time, some of their thermodynamic parameters have been optimized. The calculated results not only agree well with the measuredvalues, but also obey the mass action law rigorously, this in turn shows that these models can reflect the structural characteristics of corresponding melts. 展开更多
关键词 ACTIVITY phase diagram coexistence theory mass action concentration
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Calculating Model of Mass Action Concentrations for Fe-Cr-P Melts and Optimization of Thermodynamic Parameters 被引量:2
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作者 Jian Zhang (Metallurgy School, University of Science and Technology Beliing, Beijing 100083, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1999年第1期11-14,共4页
According to the results of research on the thermodynamic propelles of Fe-Cr, Fe-P and Cr-P melts, the measured achvihes of Fe-Cr-P melts from reference sources as well as the coexistence theory of metallic melts str... According to the results of research on the thermodynamic propelles of Fe-Cr, Fe-P and Cr-P melts, the measured achvihes of Fe-Cr-P melts from reference sources as well as the coexistence theory of metallic melts structure involving compound formation, a calculating model of the mass action concentrations for Fe-Cr-P melts has been formulated and some of its thermodynamic parameters have been optimized. The calculated mass action concentrations agree with the measured achvities, which shows that this model can reflect the structural reality of Fe-Cr-P melts. 展开更多
关键词 ACTIVITY dephosphorization of stainless steel coexistence theory mass action concentration
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Oderly accumulation theory of shale system petroleum resource and its prospecting significance-A case study of Chang 7 Member of Yanchang Formation in Ordos Basin 被引量:5
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作者 Cui Jingwei Zhu Rukai +1 位作者 Li Shixiang Zhang Zhongyi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期265-266,共2页
1 Introduction Shale formations bear abundant mineral resource and*unconventional petroleum resource,and the unconventional petroleum resource that contain in the shale formation should be integrated and researched.
关键词 In Oderly accumulation theory of shale system petroleum resource and its prospecting significance-A case study of Chang 7 Member of Yanchang formation in Ordos Basin
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String Gauge Symmetries in the Conformally Gauge-Fixed Polyakov D1 Brane Action in the Presence of Background Gauge Fields 被引量:1
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作者 Usha Kulshreshtha Daya Shankar Kulshreshtha 《Journal of Modern Physics》 2012年第1期110-115,共6页
Recently we have studied the instant-form quantization (IFQ) and the light-front quantization (LFQ) of the conformally gauge-fixed Polyakov D1 brane action using the Hamiltonian and path integral formulations. The IFQ... Recently we have studied the instant-form quantization (IFQ) and the light-front quantization (LFQ) of the conformally gauge-fixed Polyakov D1 brane action using the Hamiltonian and path integral formulations. The IFQ is studied in the equal world-sheet time framework on the hyperplanes defined by the world- sheet time σ0 = τ = constant and the LFQ in the equal light-cone world-sheet time framework, on the hyperplanes of the light-front defined by the light-cone world-sheet time . The light-front theory is seen to be a constrained system in the sense of Dirac in contrast to the instant-form theory. However, owing to the gauge anomalous nature of these theories, both of these theories are seen to lack the usual string gauge symmetries defined by the world-sheet reparametrization invariance (WSRI) and the Weyl invariance (WI). In the present work we show that these theories when considered in the presence of background gauge fields such as the NSNS 2-form gauge field or in the presence of gauge field and the constant scalar axion field , then they are seen to possess the usual string gauge symmetries (WSRI and WI). In fact, these background gauge fields are seen to behave as the Wess-Zumino/Stueckelberg fields and the terms containing these fields are seen to behave as Wess-Zumino or Stueckelberg terms for these theories. 展开更多
关键词 LIGHT-FRONT QUANTIZATION Hamiltonian QUANTIZATION Path Integral QUANTIZATION Constrained Dynamics Constraint QUANTIZATION GAUGE SYMMETRY STRING GAUGE SYMMETRY STRING theory D-BRANE actions Polyakov action Light-Cone QUANTIZATION
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Light-Front Hamiltonian and Path Integral Formulations of the Conformally Gauge-Fixed Polyakov D1 Brane Action 被引量:1
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作者 Usha Kulshreshtha Daya Shankar Kulshreshtha 《Journal of Modern Physics》 2011年第5期335-340,共6页
In a recent paper we have studied the Hamiltonian and path integral quantizations of the conformally gauge-fixed Polyakov D1 brane action in the instant-form of dynamics using the equal world-sheet time framework on t... In a recent paper we have studied the Hamiltonian and path integral quantizations of the conformally gauge-fixed Polyakov D1 brane action in the instant-form of dynamics using the equal world-sheet time framework on the hyperplanes defined by the world- sheet time . In the present work we quantize the same theory in the equal light-cone world-sheet time framework, on the hyperplanes of the light-front defined by the light-cone world-sheet time , using the standard constraint quantization techniques in the Hamiltonian and path integral formulations. The light-front theory is seen to be a constrained system in the sense of Dirac, which is in contrast to the corresponding case of the instant-form theory, where the theory remains unconstrained in the sense of Dirac. The light-front theory is seen to possess a set of twenty six primary second-class contraints. In the present work Hamiltonian and path integral quantizations of this theory are studied on the light-front. 展开更多
关键词 LIGHT-FRONT QUANTIZATION HAMILTONIAN QUANTIZATION Path Integral QUANTIZATION Constrained Dynamics Constraint QUANTIZATION GAUGE SYMMETRY STRING GAUGE SYMMETRY STRING theory D-brane actions Polyakov action Light-Cone Quantization.
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Climate Change from the Perspective of Soil and Water Ecological Theory 被引量:2
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作者 Fazheng SUN 《Meteorological and Environmental Research》 CAS 2021年第4期9-12,共4页
The earth s ecological environment is declining at an unprecedented rate,and human survival is facing great risks.Among the global changes,the most serious ones are climate change and global warming.Analyzed from the ... The earth s ecological environment is declining at an unprecedented rate,and human survival is facing great risks.Among the global changes,the most serious ones are climate change and global warming.Analyzed from the theory of soil and water ecology,the root cause of this problem lies in the disordered and uncontrolled human activities,which only pay attention to the interests of development and ignore the purpose of development.From the source,it is the consequence of human excessive interference and damage to the earth s water and soil ecology.It is urgent to protect and repair the earth s water and soil ecology,realize carbon neutralization as soon as possible,and prevent the irreversible disaster caused by global warming from the source. 展开更多
关键词 Climate change Global warming Carbon neutralization Soil and water ecology Soil and water ecological theory
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