Improving health care through community OR

Two examples of Community OR (COR) applied to public and patient involvement in improving health services in the UK are described—the Hull and East Riding Impact project and Trailblazers. These projects are consumer controlled but professionally facilitated. The team members have or have had mental illnesses but are committed to improving mental health services by applying COR methods. These projects illustrate how COR can contribute to the improvement of health services by enabling service users to take the lead in facilitating multi-stakeholder planning and problem solving. The Impact team produced a tool based around Ulrich's critical heuristics and have used this in several successful consultations in the NHS. The Trailblazer project used an idealized planning approach in a novel way to produce a distance method of consultation aimed at enabling stakeholders to negotiate commitments to action. Longer-term evaluation of these approaches is planned.     

Managing Cost Overrun Risk in Project Funding Allocation

This paper discusses decision making of project funding allocation under uncertain project costs. Because project costs are uncertain and funding allocations may not necessarily match the costs required, each project is inherently subject to a cost overrun risk (COR). In this paper, a model is proposed in which project cost is treated as a factor with a probability density function. The decision maker then allocates the total funding to the projects while minimizing a weighted sum of mean and variance of the COR of the project portfolio. Some properties of project COR are derived and interpreted. Optimal funding allocation, in relationship to factors such as various project sizes and riskiness, project interdependency, and the decision maker’s risk preference, is analyzed. The proposed funding allocation model can be integrated with project selection decision-making and provides a basis for more effective project control.     

Designing a recovery-orientated system of care: A community operational research perspective

Theory suggests health focused Community Operational Research (COR) projects and their participants can benefit from balancing a “glass half empty” concern for deficits, problems and weaknesses with a “glass half full” concern for identifying health assets and bringing them into use. We present a COR systemic intervention in the care of persons with addiction and substance use/ misuse problems in Clydeplace, Scotland (anonymised). Our research reveals how the Whole Person Recovery System is situated within a wider General Community Recovery System that offers a variety of health assets that can be mobilised to create and increase recovery capital. The project involved 20 semi-structured interviews, two asset mapping workshops, a certificated “health issues” course completed by seven “champions”, and action planning and implementation. In the interviews participants found gaps were more easily identified than assets. During the workshops participants identified 388 discrete assets and gaps, prioritised these using a simple voting system and developed a series of actions to mobilise health assets including bringing into use local facilities and amenities and involving a number of individuals and groups in local events and activities. Our study suggests that even in the impoverished system of Clydeplace, a “Community Catalyst” in the form of a Community Operational Researcher can act to stimulate the co-development of health assets, build relationships and enable the creation of social capital. It is not clear though when such systems become “self-catalysing.”     

Temporal Taylor’s scaling of facial electromyography and electrodermal activity in the course of emotional stimulation

High frequency psychophysiological data create a challenge for quantitative modeling based on Big Data tools since they reflect the complexity of processes taking place in human body and its responses to external events. Here we present studies of fluctuations in facial electromyography (fEMG) and electrodermal activity (EDA) massive time series and changes of such signals in the course of emotional stimulation. Zygomaticus major (ZYG; “smiling” muscle) activity, corrugator supercilii (COR; “frowning” muscle) activity, and phasic skin conductance (PHSC; sweating) levels of 65 participants were recorded during experiments that involved exposure to emotional stimuli (i.e., IAPS images, reading and writing messages on an artificial online discussion board). Temporal Taylor’s fluctuations scaling were found when signals for various participants and during various types of emotional events were compared. Values of scaling exponents were close to one, suggesting an external origin of system dynamics and/or strong interactions between system’s basic elements (e.g., muscle fibres). Our statistical analysis shows that the scaling exponents enable identification of high valence and arousal levels in ZYG and COR signals.     

A new proposed model of restricted data envelopment analysis by correlation coefficients

The concept of efficiency in data envelopment analysis (DEA) is defined as weighted sum of outputs/weighted sum of inputs. In order to calculate the maximum efficiency score, each decision making unit (DMU)’s inputs and outputs are assigned to different weights. Hence, the classical DEA allows the weight flexibility. Therefore, even if they are important, the inputs or outputs of some DMUs can be assigned zero (0) weights. Thus, these inputs or outputs are neglected in the evaluation. Also, some DMUs may be defined as efficient even if they are inefficient. This situation leads to unrealistic results. Also to eliminate the problem of weight flexibility, weight restrictions are made in DEA. In our study, we proposed a new model which has not been published in the literature. We describe it as the restricted data envelopment analysis ((ARIII(COR))) model with correlation coefficients. The aim for developing this new model, is to take into account the relations between variables using correlation coefficients. Also, these relations were added as constraints to the CCR and BCC models. For this purpose, the correlation coefficients were used in the restrictions of input–output each one alone and their combination together. Inputs and outputs are related to the degree of correlation between each other in the production. Previous studies did not take into account the relationship between inputs/outputs variables. So, only with expert opinions or an objective method, weight restrictions have been made. In our study, the weights for input and output variables were determined, according to the correlations between input and output variables. The proposed new method is different from other methods in the literature, because the efficiency scores were calculated at the level of correlations between the input and/or output variables.     

Teaching communication in an MBA operations research/management science course

This paper discusses the inclusion of a writing requirement within a first-year Operations Research/Management Science (OR) course of a Masters of Business Administration (MBA) curriculum. The inclusion of a writing requirement addresses the importance of communication in OR. It is the authors’ supposition that many of the recent criticisms of OR teaching have their roots in poor OR communication. Although OR faculty members can well argue relative values, we have failed to adequately prepare our students to communicate relevant insights from OR studies. The integration of a writing requirement, consisting of short executive summary-style reports and a major term project, within an MBA OR course can do much in promoting further OR study and OR work. This paper describes our experience in instituting a writing requirement within a first-year MBA course in OR.     

On electromagnetic waves in complex linear media in nonsmooth domains

Electromagnetic wave propagation in more complex linear materials such as bi‐anisotropic media have come to a considerable attention within the last 15–20 years. We shall propose a general framework to approach a class of highly complex materials. Such problems have been extensively studied mostly in the time‐harmonic case. In this paper, we focus on the time‐dependent case. A well‐posedness result for a large class of media is obtained. We also analyze Drude–Born–Fedorov type media in nonsmooth domains of arbitrary topological genus within this framework. Copyright © 2012 John Wiley & Sons, Ltd.     

Modelling the diffusion of lead into drinking water

The use of lead in pipe networks, and the subsequent lead emissions into drinking water, is now a major concern to the European Union Member States. Computer simulation offers the possibility for achieving a greater understanding of the issues that relate to plumbosolvency control. An analytical and a numerical scheme for the diffusion of lead into drinking water within a pipe during a stagnation period are described. These have been validated by experimental work. Three models have been investigated to simulate the flow of water through a pipe. These flow models have been used in conjunction with the equation of mass transfer to simulate the concentration of lead at the tap. This has been used within a Monte Carlo framework in order to simulate a zone of properties. The zonal output data obtained consists of failure rates at specified lead standards. This data can be utilised to investigate and prioritise plumbosolvency control options, and substantially overcomes the severe limitations of sampling.     

Minimizing the number of machines with limited workload capacity for scheduling jobs with interval constraints

In this paper, we consider a parallel machine scheduling problem in which machines have a limited workload capacity and jobs have deadlines and release dates. The problem is motivated by the operation of energy storage management systems for microgrids under emergency conditions and generalizes some problems that have already been studied in the literature for their theoretical value. In this work, we propose heuristic and exact algorithms to solve the problem. The heuristics are adaptations of classical bin packing heuristics in which additional conditions on the feasibility of a solution are imposed, whereas the exact method is a branch-and-price approach. The results show that the branch-and-price approach is able to optimally solve random instances with up to 250 jobs within a time limit of one hour, while the heuristic procedures provide near optimal solution within reduced running times. Finally, we also provide additional complexity results for a special case of the problem.     

Metropolis-Hastings Within Partially Collapsed Gibbs Samplers

The partially collapsed Gibbs (PCG) sampler offers a new strategy for improving the convergence of a Gibbs sampler. PCG achieves faster convergence by reducing the conditioning in some of the draws of its parent Gibbs sampler. Although this can significantly improve convergence, care must be taken to ensure that the stationary distribution is preserved. The conditional distributions sampled in a PCG sampler may be incompatible and permuting their order may upset the stationary distribution of the chain. Extra care must be taken when Metropolis-Hastings (MH) updates are used in some or all of the updates. Reducing the conditioning in an MH within Gibbs sampler can change the stationary distribution, even when the PCG sampler would work perfectly if MH were not used. In fact, a number of samplers of this sort that have been advocated in the literature do not actually have the target stationary distributions. In this article, we illustrate the challenges that may arise when using MH within a PCG sampler and develop a general strategy for using such updates while maintaining the desired stationary distribution. Theoretical arguments provide guidance when choosing between different MH within PCG sampling schemes. Finally, we illustrate the MH within PCG sampler and its computational advantage using several examples from our applied work.     

Concurrent optimization in designing for logistics support

Concurrent Engineering has always been an important field within military industry and is gaining recognition within commercial industry as well. Studies have suggested that long-range research efforts need to be directed to the area of integrated logistics. In order to satisfy the overall logistics objectives, product designs must incorporate consideration of the impact that design decisions have on operations, maintenance, transportation and supply. This paper presents a model that carries out a concurrent optimization of a product design and its associated manufacturing and logistics support systems. We offer this model as a framework for decision support of concurrent engineering activities.     

HOW DOES THE WAY IN WHICH INDIVIDUAL STUDENTS BEHAVE AFFECT THE SHARED CONSTRUCTION OF MEANING?

Audio taped discussions between three students have been examined to shed light on the way in which the behaviour of individual students may affect the shared construction of meaning with graphical calculators. These discussions revealed a complex pattern of interaction between the students. Each student was responsible for defining his or her own role within the discourse and these roles appeared to change as the discussion progressed. With reference to the framework offered by Winbourne and Watson (1998), it is proposed that local communities of practice have been established and that the individual student's positioning within the community of practice determines their success as a learner and contributes towards the creation of shared knowledge.     

Statistics on wreath products and generalized binomial-stirling numbers

Various statistics on wreath products are defined via canonical words, “colored” right to left minima and “colored” descents. It is shown that refined counts with respect to these statistics have nice recurrence formulas of binomial-Stirling type. These extended Stirling numbers determine (via matrix inversion) dual systems, which are also shown to have combinatorial realizations within the wreath product. The above setting also gives rise to a MacMahon-type equi-distribution theorem over subsets with prescribed statistics. Partially supported by Minerva Grant No. 8441 and by EC's IHRP Programme, within the Research Training Network “Algebraic Combinatorics in Europe”, grant HPRN-CT-2001-00272. Partially supported by EC's IHRP Programme, within the Research Training Network “Algebraic Combinatorics in Europe”, grant HPRN-CT-2001-00272.     

On linear optimization over Wasserstein balls

Mathematical Programming - Wasserstein balls, which contain all probability measures within a pre-specified Wasserstein distance to a reference measure, have recently enjoyed wide popularity in the...     

A cost-based importance measure for system components: An extension of the Birnbaum importance

In reliability engineering, component importance measures are used to prioritise components in a system for purposes such as reliability improvement and maintenance planning. Existing importance measures have paid little attention to the costs incurred by maintaining a system and its components within a given time period. Cost-effectiveness analysis, however, is critically important in increasingly competitive markets. This paper proposes a new cost-based importance measure which considers costs incurred by maintaining a system and its components within a finite time horizon. Possible extensions are discussed and examples are given to show the use of the new measure.     

Progress and stagnation of gender equity: contradictory trends within mathematics research and education in Sweden

During the last decade women in Sweden have reduced men’s lead in participation in mathematics education and in professional careers as mathematicians. However, the development is uneven and slow overall. In some areas and at the highest levels women have increased their participation only marginally. Why, one may ask, is progress so slow after almost 20 years of active work from the Women and Mathematics movement in Sweden and within a society in which gender equity is highly valued at the societal and political levels? The development is described in quantitative measures going back 20 years. Several concrete and successful initiatives from the last decade intended to “de-gender” mathematics and to involve women and men alike in mathematics are described. In contrast a gender-blind position or a view of women as problems in mathematics seems to reign within some influential bodies.     

Exploring new directions for research in problem structuring methods: on the role of cognitive style

Prior research has argued that cognitive style can have a significant impact on group decision making. In addition, several scholars have proposed that cognitive style can play a key role in the design and use of group decision support systems. However, cognitive style has not received a great deal of attention in the problem structuring methods (PSMs) community. This is surprising, given that PSMs are specifically developed to support a group in their decision making. The purpose of this paper is thus to examine the significance of cognitive style within PSMs. The paper identifies and explores the role of four different cognitive style functions in problem structuring interventions. This analysis is carried out by focusing on the different tasks embedded within a group process supported by PSMs. Implications for the research and practice of PSMs are then discussed.     

Conducting secret ballot elections in computer networks: Problems and solutions

We discuss problems related to devising a secret balloting system with the following properties: (1) all eligible voters and they only may vote, (2) all ballots are secret, i.e. do not reveal the identity of the voter, (3) all voters may check whether their ballots have been correctly assigned, (4) the voters may revise their ballots within a predetermined time, and (5) errors in ballot assignment can be corrected within a predetermined time.     

Bipolarity in argumentation graphs: Towards a better understanding

Different abstract argumentation frameworks have been used for various applications within multi-agents systems. Among them, bipolar frameworks make use of both attack and support relations between arguments. However, there is no single interpretation of the support, and the handling of bipolarity cannot avoid a deeper analysis of the notion of support.In this paper we consider three recent proposals for specializing the support relation in abstract argumentation: the deductive support, the necessary support and the evidential support. These proposals have been developed independently within different frameworks. We restate these proposals in a common setting, which enables us to undertake a comparative study of the modellings obtained for the three variants of the support. We highlight relationships and differences between these variants, namely a kind of duality between the deductive and the necessary interpretations of the support.     

Assessing the impact of problem structuring methods in multi-organizational settings: an empirical investigation

Problem structuring methods (PSMs) have most commonly been employed with groups operating within single-organizational contexts. This paper argues that PSMs are by their nature also appropriate for supporting the work of multi-organizational groups (MOGs) operating within a partnership context. An experience of the use of a PSM in this context is reported and evaluated. The research findings suggest that there is indeed scope for the use of PSMs with MOGs, and that these methods do appear to have a positive role in achieving some of the products claimed for PSM interventions. In particular, the experience as a whole tends to demonstrate that mutual accommodations between the organizations represented in the MOG can be the result of the use of PSMs. The paper concludes with a discussion of the significance of the experience, and proposes some directions for further research.