首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到17条相似文献,搜索用时 15 毫秒
1.
Systemic Practice and Action Research - Fall armyworm (FAW) infestation in African countries presents significant threats to maize production. Such infestation has major economic implications in...  相似文献   

2.
On the course of history,human beings have liberated production capacity and madeglorious achievements in economic development.However,global environmental pollutionand ecological problem have arisen as a result of irrational development and utilization o…  相似文献   

3.
Decision- making isthe whole process from discovering to solving a problem. The characterof its logic is the problem- oriented pragmatism and innovative ratiocination taking thefuture as premise. Decision- making mechanism is the operation mode that the d…  相似文献   

4.
Public spending is a major policy tool for the government to adjust the macro economic progress. This paper characterizes the effects of shocks in government spending and taxes on Chinese economy growth since 1978. It does so by using a mixed structural VAR (SVAR) approach. Identification is achieved by using institutional information about the tax and spending to identify automatic and discretionary response, and by implication, to infer fiscal shocks. The results show positive government spending shocks as having a positive effect on output, and positive tax shocks as having a negative effects.  相似文献   

5.
Liu  Qing  Liu  Xiuli 《系统科学与复杂性》2020,33(4):1126-1143
This paper explores the impacts of the universal two-child policy on Beijing's population in the long term. It gives a detail estimation of Beijing population considering the latest fertility and immigration policy and can help related government department management population. The cohortcomponent method based on a net migration was applied to project population by age for Beijing from2020 to 2050 in four fertility scenarios. The innovation is the estimation method of the mortality rate with the life table linked with life expectancy. The results show that, though the basic development trend of Beijing's population will not change essentially under the universal two-child policy, low birth rate and aging problems will be improved. Compared with the partial policy relaxation, the total population will be 876,478 persons more than that in 2050, the share of population aged 0–14 will increase 1.1 percentage points, and the aged dependency ratio will decrease 1.96 percentage points.Some measures should be taken to encourage more couples to have a second child and introduce more young talents to promote Beijing's prosperity.  相似文献   

6.

This paper explores Checkland’s Soft Systems Methodology (SSM) through the lenses of a theoretical framework that incorporates key concepts from Maturana’s Ontology of the Observer (OoO) with the view of complementing Checkland’s SSM application process. We outline and examine paradigmatic compatibility between: Checkland’s ontological position (reality is problematic/chaotic) together with his interpretivist epistemology (multiple perceptions enrich the ever-changing reality); and Maturana’s OoO (we are immersed in the praxis of living in an ontological multi-universe). We argue that OoO resonates with key SSM theoretical underpinnings. After establishing compatibility between these two influential systems thinkers, we advance a conceptual framework in which Checkland’s SSM learning process is re-visited through a the framework grounded on Maturana’s OoO. The proposed framework illustrates how key ideas drawn from Maturana’s OoO can shed light into the way in which some of the main SSM devices (i.e.: Root definitions, Conceptual model) are used in the SSM process. By doing that, SSM is enriched and becomes more flexible as the stakeholders involved are placed within the domain of constitutive ontologies from which, a deeper dialogue can be promoted in a domain of coexistence in mutual acceptance. We argue that this is a suitable way to have more flexible and holistic views for a SSM intervention in particular to promote the learning process and debating proposed changes amongst the stakeholders involved. The proposed framework, when applied, may enhance the power of SSM learning process and when adopted can have substantial implications to complement the SSM process.

  相似文献   

7.
Understanding the characteristics of the dynamic relationship between the onshore Renminbi (CNY) and the offshore Renminbi (CNH) exchange rates considering the impact of some extreme events is very important and it has wide implications in several areas such as hedging. For better estimating the dynamic relationship between CNY and CNH, the Granger-causality test and Bry-Boschan Business Cycle Dating Algorithm were employed in this paper. Due to the intrinsic complexity of the lead-lag relationships between CNY and CNH, the empirical mode decomposition (EMD) algorithm is used to decompose those time series data into several intrinsic mode function (IMF) components and a residual sequence, from high to low frequency. Based on the frequencies, the IMFs and a residual sequence are combined into three components, identified as short-term composition caused by some market activities, medium-term composition caused by some extreme events and the long-term trend. The empirical results indicate that when it only matters the short-term market activities, CNH always leads CNY; while the medium-term impact caused by those extreme events may alternate the lead-lag relationships between CNY and CNH.  相似文献   

8.
This paper studies the complete monotonicity of the probability of ruinψin the the classical risk model and the classical risk model that is perturbed by a diffusion.As a byproduct,the authors give an alternative proof to a result on the optimal dividend problem due to LoefFen(2008).  相似文献   

9.
We explore problems involving the measurement of the performance of a system. We outline two systemic approaches that have come from different epistemological positions: one from the interpretivist paradigm (soft systems methodology) and the other from the cybernetic paradigm (viable systems model). These two systemic methodologies that have tackled problems involving performance measurement are considered and discussed: (a) Checkland’s systems ideas of ‘managing and controlling’ a system throughout a set of three measures of performance: efficacy, efficiency and effectiveness; and (b) Beer’s concepts of Actuality, Capability, Potentiality of the firm and his claims that the performance of a system needs to be quantifiable and resumed on ‘pure’ numbers which should reflect the survivability of the firm. A parallel is drawn between the two approaches concluding that although the paradigms underpinning them are in some way different, the practicalities of these approaches to control, measure and improve the performance of a system are very similar. A case involving the measurement of a proposed research strategic plan for a Manchester Metropolitan University Business School’s department is used to illustrate the systemic approaches.  相似文献   

10.
Based on the information entropy, a model for water quality assessment is Using this model, the paper gives a case study on the water quality assessment River. The space-time variation law of the water quality is analyzed also in this result indicates that the model possesses some clear mathematic and physical and it is simple, practical and accurate.  相似文献   

11.
1.INTRODUCTIONDue to the process and characteristics of the non-stationary signals both in ti me and frequency do-mains,wavelet technology has been widely em-ployedin scientific research and engineering appli-cation fields[1~3].To date,wavelet algorithmthatneeds a larger number of mathematic operationsand complicated program is mainly realized bycomputer,whichis quite difficult and expensive toapplyit to engineeringfields and portable electron-ic systems.To solve these problems,we proposed…  相似文献   

12.

The algebraic methods represented by Wu’s method have made significant breakthroughs in the field of geometric theorem proving. Algebraic proofs usually involve large amounts of calculations, thus making it difficult to understand intuitively. However, if the authors look at Wu’s method from the perspective of identity,Wu’s method can be understood easily and can be used to generate new geometric propositions. To make geometric reasoning simpler, more expressive, and richer in geometric meaning, the authors establish a geometric algebraic system (point geometry built on nearly 20 basic properties/formulas about operations on points) while maintaining the advantages of the coordinate method, vector method, and particle geometry method and avoiding their disadvantages. Geometric relations in the propositions and conclusions of a geometric problem are expressed as identical equations of vector polynomials according to point geometry. Thereafter, a proof method that maintains the essence of Wu’s method is introduced to find the relationships between these equations. A test on more than 400 geometry statements shows that the proposed proof method, which is based on identical equations of vector polynomials, is simple and effective. Furthermore, when solving the original problem, this proof method can also help the authors recognize the relationship between the propositions of the problem and help the authors generate new geometric propositions.

  相似文献   

13.
This paper reports on a study in which an interpretive systems-based approach to knowledge elicitation, the Appreciative Inquiry Method (AIM), is used to elicit and record the expertise of what is referred to as a ??knowledge guardian??. A ??knowledge guardian?? is an individual who is a current repository and representative of some culturally-embedded knowledge which, for generations, has been passed on through teaching and apprenticeship, and continues to be so. Such knowledge is rich, complex and precious and merits protection. The knowledge guardian in this study is a Portuguese rider and teacher of Classical Dressage. His expertise relies heavily upon the ability to ??feel?? and explain such feeling in his teaching. The view of Classical Dressage that emerges from the study emphasises the importance of the individual??s psychological development and motivation to participate in the art due to a desire to experience ??brilliance??. The paper describes the process undertaken during the elicitation sessions and provides the models developed and used to facilitate the discussion. These models (Root Definition and Conceptual Model) are of the type commonly associated with Soft Systems Methodology. The paper also provides comments on the use of AIM, the knowledge recorded about Classical Dressage and the reflections of the two collaborators involved in the study.  相似文献   

14.
Rapid advances in machine learning combined with wide availability of online social media have created considerable research activity in predicting what might be the news of tomorrow based on an analysis of the past.In this work,we present a deep learning forecasting framework which is capable to predict tomorrow’s news topics on Twitter and news feeds based on yesterday’s content and topic-interaction features.The proposed framework starts by generating topics from words using word embeddings and K-means clustering.Then temporal topic-networks are constructed where two topics are linked if the same user has worked on both topics.Structural and dynamic metrics calculated from networks along with content features and past activity,are used as input of a long short-term memory(LSTM)model,which predicts the number of mentions of a specific topic on the subsequent day.Utilizing dependencies among topics,our experiments on two Twitter datasets and the HuffPost news dataset demonstrate that selecting a topic’s historical local neighbors in the topic-network as extra features greatly improves the prediction accuracy and outperforms existing baselines.  相似文献   

15.
ImportantDates●Submissiondue●Notificationofacceptance●Camera readycopydueNovember15,2005December30,2005January10,2006WorkshopScope IntelligenceandSecurityInformatics(ISI)canbebroadlydefinedasthestudyofthedevelopmentanduseof advancedinformationtechnologiesandsystemsfornationalandinternationalsecurity relatedapplications.TheFirst andSecondSymposiumsonISIwereheldinTucson,Arizona,in2003and2004,respectively.In2005,theIEEEInter nationalConferenceonISIwasheldinAtlanta,Georgia.TheseIS…  相似文献   

16.
We use the sociological systems theory proposed by Niklas Luhmann to complement a socially-oriented view of knowledge with the role of technical infrastructure in knowledge creation. We highlight the self-referential character of knowledge creation and draw upon illustrative examples from open-source software. We discuss why knowledge creation processes are often prone to breakdown and propose three conditions that may stabilize knowledge creation processes: perceptibility, systemic memory, and modularity.  相似文献   

17.
This paper follows several case studies where the children’s services departments of English and Welsh local authorities have fundamentally redesigned the way they worked following the application of the Vanguard Method (Seddon, Systems thinking in the public sector, 2008), a particular form of systems thinking. After first studying the way the children’s social care service worked as a system, the social workers in these authorities were able to demonstrate the way that government-prescribed IT and performance measures were restricting the way they could do what was shown to matter to the children in their care. The paper will document how, after being granted ministerial permission to suspend the use of their old performance measures and IT, a new set of operating principles was developed and employed. The redesigned system has shown encouraging early results. Evidence from these case studies (following Yin 2009) is presented in the form of recorded operational improvements and statements from participants. The paper will be of topical relevance to all involved in social care in the light of the government-commissioned Munro Review (Munro, The Munro Review of child protection: final report, 2011). The issues discussed will also be germane to the many other public sector partner agencies involved in the delivery of social care services (e.g. police, health, housing associations).  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号