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1.
The European Union’s efforts for poverty reduction are based on the principle of Sustainable Human Development. Meeting the terms of this principle entails the consideration of aspects of general interest, known as “cross-cutting issues”, at all levels of intervention. Cross-cutting issues comprise issues like human rights, gender equity, environmental concern, democracy as a social value, or the participation and empowerment of the beneficiaries of development. These issues concern social phenomena that are difficult to isolate in time or capture empirically, causing operational difficulties when projects are subjected to evaluation. Traditional methods of project evaluation, such as Cost Benefit Analysis or the Logic Framework, struggle to incorporate impacts that are difficult to measure or estimate in terms of indicators or monetary value. Therefore, in the field work at a rural development programme located in Bolivia, a need arose spontaneously to find and implement an approach that, complementary to traditional methods of project evaluation, could allow project managers to keep an eye on project performances in terms of cross-cutting issues. This article describes how the MACBETH multicriteria approach was implemented in practice, in order to help an important rural development programme build a project evaluation tool, taking into account cross-cutting issues through a series of interviews and decision conferences attended by specialists and the programme staff.  相似文献   

2.
The problem of students entering university lacking basic mathematical skills is a critical issue in the Australian higher-education sector and relevant globally. The Maths Skills programme at La Trobe University has been developed to address under preparation in the first-year science cohort in the absence of an institutional mathematics support centre. The programme was delivered through first-year science and statistics subjects with large enrolments and focused on basic mathematical skills relevant to each science discipline. The programme offered a new approach to the traditional mathematical support centre or class. It was designed through close collaboration between science subject coordinators and the project leader, a mathematician, and includes resources relevant to science and mathematics questions written in context. Evaluation of the programme showed it improved the confidence of the participating students who found it helpful and relevant. The programme was delivered through three learning modes to allow students to select activities most suitable for them, which was appreciated by students. Mathematics skills appeared to increase following completion of the programme and student participation in the programme correlated positively and highly with academic grades in their relevant science subjects. This programme offers an alternative model for mathematics support tailored to science disciplines.  相似文献   

3.
The minimax relative regret solution to a linear programme with interval objective function coefficients can be found using an algorithm that, at each iteration, solves a linear programme to generate a candidate solution and a mixed integer programme (MIP) to find the corresponding maximum regret. This paper first shows that there exists a regret-maximising solution in which all uncertain costs are at a bound, and then uses this to derive a MIP formulation that maximises the regret of a candidate solution. Computational experiments demonstrate that this approach is effective for problems with up to 50 uncertain objective function coefficients, significantly improving upon the existing enumerative method.  相似文献   

4.
Applications and modelling have gained a prominent role in mathematics education reform documents and curricula. Thus, there is a growing need for studies focusing on the effective use of mathematical modelling in classrooms. Assessment is an integral part of using modelling activities in classrooms, since it allows teachers to identify and manage problems that arise in various stages of the modelling process. However, teachers’ difficulties in assessing student modelling work are a challenge to be considered when implementing modelling in the classroom. Thus, the purpose of this study was to investigate how teachers’ knowledge on generating assessment criteria for assessing student competence in mathematical modelling evolved through a professional development programme, which is based on a lesson study approach and modelling perspective. The data was collected with four teachers from two public high schools over a five-month period. The professional development programme included a cyclical process, with each cycle consisting of an introductory meeting, the implementation of a model-eliciting activity with students, and a follow-up meeting. The results showed that the professional development programme contributed to teachers’ knowledge for generating assessment criteria on the products, and the observable actions that affect the modelling cycle.  相似文献   

5.
The high cost of maintenance in the processing industry implies the need for optimal planning of maintenance strategy. In order to achieve this there is a need to understand the underlying failure processes, which are often very complex. In this paper, a new semi-parametric approach, combining Cox regression with density kernal smoothing, is introduced to estimate the underlying performance. The approach has been applied to several processes and it allowed insight into each process, which would not have been achieved if traditional approaches had been used. Particularly, the refurbishment of processes had a significant impact on the rate failure. This paper concludes by assessing this impact of refurbishment on the maintenance programme.  相似文献   

6.
Dynamic location-routeing problems involve the determination of the least-cost sequence of depot, vehicle fleet and route configurations in a distribution system, over a given planning horizon. This paper presents two solution approaches to such problems. The first is an exact method which is appropriate for small-scale problems. It consists of representing the problem by a suitable network and of solving to optimality an integer linear programme associated with the network. In the second approach, some of the system costs are approximated, and a global solution is then obtained by determining a shortest path on a directed graph. Under some hypotheses, this approach is suitable for large-scale problems. It is illustrated on a simple example.  相似文献   

7.
Estimation errors or uncertainities in expected return and risk measures create difficulties for portfolio optimization. The literature deals with the uncertainty using stochastic, fuzzy or probability programming. This paper proposes a new approach to treating uncertainty. By assuming that the expected return and risk vary within a bounded interval, this paper uses interval analysis to extend the classical mean-variance portfolio optimization problem to the cases with bounded uncertainty. To solve the interval quadratic programming problem, the paper adopts order relations to transform the uncertain programme into a deterministic programme, and includes the investors’ risk preference into the model. Numerical analysis illustrates the advantage of this new approach against conventional methods.  相似文献   

8.
本文采用JIGFEX程序系统,将高层建筑结构作为空间体系进行了较精确的空间静力、动力分析.对地震力和地震扭矩的计算提出了建议.为在中小型计算机上对大型复杂结构进行空间静力、动力分析提供了一个切实可行的计算途径.文内附有实际工程的计算结果和图表.  相似文献   

9.
郭宁  郭鹏  刘洋 《运筹与管理》2021,30(2):196-201
运用复杂网络研究并联式项目群的结构脆弱性。将项目群中的任务用节点表示、任务之间的依赖关系用边表示,依据任务的工期确定点权、任务之间的依赖强度确定边权,则并联式项目群被抽象为一个有向加权网络。在分析并联式项目群网络拓扑特征的基础上,构建并联式项目群脆弱性评估模型,并对一个并联式项目群进行脆弱性评估。仿真结果表明该方法可以对并联式项目群脆弱性进行定量化评估、能够有效识别结构中的脆弱环节。本研究为保障项目群顺利实施、抵御风险提供了新的思路。  相似文献   

10.
A multistep approach to determining the optimal parameters of an exponential smoothing model was used to forecast emergency medical service (E.M.S.) demand for four counties of South Carolina. Daily emergency and routine (non-emergency) demand data were obtained and forecast statistics generated for each county sampled, using Winters' exponential smoothing model. A goal programme was formulated to combine forecast results for emergency calls with routine call forecasts. The goal programme gave a higher priority to accurate forecasting of emergency demand. The forecast model generated implicitly weights demand by severity and provides a reliable estimate of demand overall. The optimal parameter values for the smoothing model were obtained by minimizing the objective function value of the goal programming problem. The parameter values obtained were used to forecast demand for E.M.S. in the selected counties. The results of the model were compared to those using a multiple linear regression model and a single-objective-based exponential smoothing model for 2 months of data. When compared with two single-objective forecast models, the multiple-objective approach yielded more accurate forecasts and, therefore, was more cost-effective for the planner. The model presents and demonstrates a theoretical approach to improving the accuracy of ambulance demand forecasts. The possible impact of this approach on planning efficiency is discussed.  相似文献   

11.
A crucial property of second order fluid models is the behaviour of the fluid level at the boundaries. Two cases have been considered: the reflecting and the absorbing boundary. This paper presents an approach for the stationary analysis of second order fluid models with any combination of boundary behaviours. The proposed approach is based on the solution of a linear system whose coefficients are obtained from a matrix exponent. A practical example demonstrates the suitability of the technique in performance modeling. This work is partially supported by the Italian-Hungarian bilateral R&D programme, by OTKA grant n. T-34972, by Italian Ministry for University and Research (MIUR) through PRIN project Famous and by EEC project Crutial.  相似文献   

12.
13.
This paper addresses the issue of collegiate mathematics achievement of underrepresented minority students as it investigates the impact of a cooperative learning calculus programme on the first-year calculus experience of non-Asian ethnic minority engineering students. The Emerging Ethnic Engineers Programme in the College of Engineering at the University of Cincinnati is a successful, comprehensive programme that focuses on the recruitment, retention, academic success, professional development, and timely graduation of underrepresented coloured students. The objectives of the programme are accomplished through three interrelated phases: pre-college science and mathematics programmes, first-year collegiate programmes, and upper-division programmes. The underlying principles of the first-year programme include academic achievement and establishing a strong sense of community among the cohort. This report will focus on the cooperative learning calculus programme that has been successful in improving retention and academic success rates for coloured freshmen engineering students.  相似文献   

14.
Applying the systems approach in practice requires compromises to be made in its ideals. This paper discusses this problem by examining two case studies of programme budgeting which can be seen to be an application of the systems approach; it attempts to expand the dimensions of budgeting away from an annual exercise based on functions to a process of medium-term planning based on programmes. The two case studies are the introduction and suspension of Planning-Programming-Budgeting-System (P.P.B.S.) in U.S. Federal Government and the various developments in the U.K. in the Public Expenditure Survey (P.E.S.C.). These provide illuminating contrasts in their intended scope and successful implementation. This contrasting experience suggests questions about systems theory. Should the essential characteristic of the systems approach be expansionism or adaptability? Can systems writing afford to ignore compromises necessary to achieve implementation, especially those made to satisfy political interests?  相似文献   

15.
Computability theory concerns information with a causal-typically algorithmic-structure. As such, it provides a schematic analysis of many naturally occurring situations. Emil Post was the first to focus on the close relationship between information, coded as real numbers, and its algorithmic infrastructure. Having characterised the close connection between the quantifier type of a real and the Turing jump operation, he looked for more subtle ways in which information entails a particular causal context. Specifically, he wanted to find simple relations on reals which produced richness of local computability-theoretic structure. To this extent, he was not just interested in causal structure as an abstraction, but in the way in which this structure emerges in natural contexts. Post’s programme was the genesis of a more far reaching research project.In this article we will firstly review the history of Post’s programme, and look at two interesting developments of Post’s approach. The first of these developments concerns the extension of the core programme, initially restricted to the Turing structure of the computably enumerable sets of natural numbers, to the Ershov hierarchy of sets. The second looks at how new types of information coming from the recent growth of research into randomness, and the revealing of unexpected new computability-theoretic infrastructure. We will conclude by viewing Post’s programme from a more general perspective. We will look at how algorithmic structure does not just emerge mathematically from information, but how that emergent structure can model the emergence of very basic aspects of the real world.  相似文献   

16.
In this paper, we explore a novel approach for assessing the impact of a professional development programme on classroom practice of in-service middle school mathematics teachers. The particular focus of this study is the assessment of the impact on teachers’ employment of strategies used in the classroom to foster the mathematical habits of mind and mathematical self-efficacy of their students. We describe the creation and testing of a student survey designed to assess teacher classroom practice based primarily on students’ ratings of teacher practices.  相似文献   

17.
This paper describes a feasibility study for the development of a network of employment services for people with mental health problems (and others) who are unemployed. It highlights the problems of using debate-orientated, soft OR methods when there are difficulties of open communication between different interest groups. In this case, the interest groups were clients and professionals in the mental health system. To bypass these difficulties, a series of confidential interviews was conducted with stakeholders. The issue of who was to be interviewed was resolved through a rolling programme of recommendations, where each interviewee recommended others until most of the people being recommended were people who had already been seen. This approach allowed for the involvement of many people and agencies who the researchers did not initially suspect might be stakeholders. Having conducted the interviews, the researchers then produced a design in the form of an ‘expert’ report. Although they had serious reservations about taking such an approach instead of simply supporting the expertise of already identified stakeholders, it turned out, upon reflection, that they had made the right decision. The ‘expert’ appoach allowed the views of service users to be taken into account. Also, the rolling programme of recommendations used to determine who should be interviewed actually uncovered hitherto ‘hidden’ stakeholders who were crucial to the success or failure of the whole project.  相似文献   

18.
MPLS (Multiprotocol Label Switching) enables the utilisation of explicit routes and other advanced routing mechanisms in multiservice packet networks, capable of dealing with multiple and heterogeneous QoS (Quality of Service) parameters. Firstly the paper presents a discussion of conceptual and methodological issues raised by multiobjective routing optimisation models for MPLS networks. The major contribution is the proposal of a multiobjective routing optimisation framework for MPLS networks. The major features of this modelling framework are: the formulation of a three-level hierarchical routing optimisation problem including network and service performance objectives, the inclusion of fairness objectives in the different levels of optimisation and a two-level stochastic representation of the traffic in the network (traffic flow and packet stream levels). A variant of the general model for two classes of traffic flows, QoS traffic and Best Effort traffic, is also presented. Finally a stochastic teletraffic modelling approach, underlying the optimisation model, is fully described. Work partially supported by programme POSI of the III EC programme cosponsored by FEDER and national funds.  相似文献   

19.
Safety cameras have been central to strategy for improving road safety in the UK (and other countries) over the past decade and a National Safety Camera (NSC) programme was introduced in the year 2000 to fund and guide the expansion of camera sites. This programme was brought to an end in 2007 and responsibility for decisions on expanding, maintaining or rolling back safety cameras has now been largely devolved to local highway authorities and their partners. To make strategic choices in such areas it is clearly vital to understand the extent to which safety cameras are effective in reducing road accident potential. Although the NSC programme has been evaluated this work has focussed mainly on assessments of impacts at camera sites rather than wider area effects: particularly local highway area effects. The research reported here has explored the rates of personal injury collisions (PIC) over the past decade on the roads of English Local Authority areas and investigated relationships between area characteristics including levels of safety camera introductions and the PIC improvements (or otherwise) reported. To assist in this analysis, an indicator of safety camera intensity has been derived in this research to reflect the relative likelihood in areas of coming into contact with safety camera sites This work shows that area improvement rates differ significantly on an urban/rural dimension and are also very dependent on prior (to camera introductions) levels of PIC risk. Controlling for these factors using a pair comparison approach, analysis shows that safety camera introduction effects are statistically detectable in very highly urbanised, high PIC risk areas and at high risk sites within areas but not elsewhere. Whilst recognising that new high risk sites can emerge in any area, the conclusion is reached that many local areas and especially more rural areas would be unlikely to gain advantage from a further general expansion of fixed point and mobile camera sites and that de-commissioning of current sites should be seriously considered.  相似文献   

20.
When implementing, the solution of single-objective unit commitment models may be dissatisfactory or inapplicable. This might mainly be due to not considering the secondary conflicting objectives from the policy-making in internal/external environment of generation companies in the developed models. To attain a practical compromised multi-objective solution for the short-term unit commitment in the deregulated hybrid markets, a novel fuzzy mixed integer linear goal programme is developed in which several complementary objectives with lower relative importances are also incorporated. Non-linear characteristic curves of the generating units are approximated through the piece-wise linear functions. The fuzzy approach is proposed to handle the imprecise nature of the goals’ target levels and priorities as well as some critical data. The critical aspects of power systems are considered in the model. The efficiency of the proposed approach is demonstrated using the experimental results inspired by a real case. The applicable nice feature of our model is that it can easily and efficiently be matched with a various line of unit commitment problems.  相似文献   

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