Supply chain collaboration under uncertainty

In fluctuating economic conditions such as global recession, supply chains operate under changing conditions of uncertainty. The impact of this uncertainty and associated risk might be mitigated by collaboration. This paper proposes a model of supply chain collaboration based on information exchange and decision coordination at both the strategic and tactical levels. However, a collaborative supply chain can be exposed to associated risks such as the failure of individual actors. Governance regimes can facilitate collaboration at the strategic and tactical level and mitigate valid apprehensions about collaboration that the actors may have. Governance can be considered as a critical factor in achieving collaboration. The paper argues for explicit rules to regulate information exchange and decision coordination at the strategic and tactical level. An illustrative case study of an automotive supplier from the electronics industry is used to explain the model

A Method for Improving Overlapping of Testing and Design

Testing is a critical activity in product development. The academic literature provides limited insight about overlapping between upstream testing and downstream design tasks, especially in considering the qualitative differences between activities that are overlapped. In general, the existing literature treats two overlapped sequential activities as similar, and suggests optimal overlapping policies, techniques, and time–cost assessment. However, this case study-based research identifies that the overlapping of upstream testing with downstream design activities has different characteristics than the overlapping of two design activities. This paper first analyzes the characteristics that affect the overlapping of upstream testing and downstream design activities, and then proposes a method to reduce the time of rework in cases where the upstream testing is overlapped with subsequent redesign phases

Improving overlapping between testing and design in engineering product development processes

Testing components, prototypes and products comprise essential, but time consuming activities throughout the product development process particularly for complex iteratively designed products. To reduce product development time, testing and design processes are often overlapped. A key research question is how this overlapping can be planned and managed to minimise risks and costs. The first part of this research study investigates how a case study company plans testing and design processes and how they manage these overlaps. The second part of the study proposes a significant modification to the existing process configuration for design and testing, which explicitly identifies virtual testing, that is an extension to Computer Aided Engineering which mirrors the testing process through product modelling and simulation, as a distinct and significant activity used to (a) enhance and (b) replace some physical tests. The analysis shows how virtual testing can mediate information flows between overlapping (re)design and physical tests. The effects of virtual testing to support overlap of test and (re)design is analysed for the development phases of diesel engine design at a case study company. We assess the costs and risks of overlaps and their amelioration through targeted virtual testing. Finally, using the analysis of the complex interactions between (re)design, physical and virtual testing, and the scope for replacing physical with virtual testing is examined

Employee burnout and job retention scores among EMS workers in Vermont

Objective: To assess whether shift length and employment status were positively associated with increased burnout and retention among emergency medical service (EMS) workers in the state of Vermont. Methods: We conducted a secondary analysis of cross-sectional data using the Vermont EMS Retention Survey from the Vermont Department of Health. 545 participants provided data from August to November 2019. Measures included burnout and retention using the Maslach Burnout Inventory. Results: In an adjusted model, the 24-hour shift length was associated with higher burnout compared to the eight-hour shift. Volunteer workers displayed lower instances of burnout and had higher retention rates than their paid counterparts. Conclusions: These findings suggest that in some cases, shift length and employment status may relate to burnout and retention. These relationships could inform policies related to staffing and scheduling of EMS workers. Further research could assess a predictive relationship between shift length, employment status and burnout or retention

DETC2005-85394 PREDICTABILITY OF CHANGE IN ENGINEERING: A COMPLEXITY VIEW

ABSTRACT Design changes can be surprisingly complex. We examine the problems they cause and discuss the problems involved in predicting how changes propagate, based on empirical studies. To assist this analysis we distinguish between (a) a static background of connectivities (b) descriptions of designs, processes, resources and requirements and (c) the dynamics of design tasks acting on descriptions. The background might consist of existing designs and subsystems, or established processes used to create them. The predictability of design change is examined in terms of this model, especially the types and scope of uncertainties and where complexities arise. An industrial example of change propagation is presented in terms of the background (connectivity) -description -action model

Cryptic genetic subdivision in the San Benito evening primrose (Camissonia benitensis)

When rare plants are distributed across a range of habitats, ecotypic differentiation may arise requiring customized conservation measures. The rate of local adaptation may be accelerated in complex landscapes with numerous physical barriers to gene flow. In such cases, examining the distribution of genetic diversity is essential in determining conservation management units. We investigated the distribution of genetic diversity in the federally threatened Camissonia benitensis (Onagraceae), which grows in two distinct serpentine habitats across several watersheds in San Benito, Fresno, and Monterey Cos., CA, USA. We compared genetic diversity with that of its two widespread relatives, C. contorta and C. strigulosa, and examined the potential for hybridization with the latter species. Genotyping results using seven heterospecific microsatellite markers indicate that differentiation between habitat types was weak (F ST = 0.0433) and in an AMOVA analysis, there was no significant partitioning of molecular variation between habitats. Watersheds accounted for 11.6 % of the molecular variation (pairwise F ST = 0.1823–0.4275). Three cryptic genetic clusters were identified by InStruct and STRUCTURE that do not correlate with habitat or watershed. C. benitensis exhibits 5–11× higher inbreeding levels and 0.54× lower genetic diversity in comparison to its close relatives. We found no evidence of hybridization between C. benitensis and C. strigulosa. To maximize conservation of the limited amount of genetic diversity in C. benitensis, we recommend mixing seed representing the three cryptic genetic clusters across the species’ geographic range when establishing new populations

Supporting change processes in design: Complexity, prediction and reliability

Change to existing products is fundamental to design processes. New products are often designed through change or modification to existing products. Specific parts or subsystems are changed to similar ones whilst others are directly reused. Design by modification applies particularly to safety critical products where the reuse of existing working parts and subsystems can reduce cost and risk. However change is rarely a matter of just reusing or modifying parts. Changing one part can propagate through the entire design leading to costly rework or jeopardising the integrity of the whole product. This paper characterises product change based on studies in the aerospace and automotive industry and introduces tools to aid designers in understanding the potential effects of change. Two ways of supporting designers are described: probabilistic prediction of the effects of change and visualisation of change propagation through product connectivities. Change propagation has uncertainties which are amplified by the choices designers make in practice as they implement change. Change prediction and visualisation is discussed with reference to complexity in three areas of product development: the structural backcloth of connectivities in the existing product (and its processes), the descriptions of the product used in design and the actions taken to carry out changes

Testing in the incremental design and development of complex products

Testing is an important aspect of design and development which consumes significant time and resource in many companies. However, it has received less research attention than many other activities in product development, and especially, very few publications report empirical studies of engineering testing. Such studies are needed to establish the importance of testing and inform the development of pragmatic support methods. This paper combines insights from literature study with findings from three empirical studies of testing. The case studies concern incrementally developed complex products in the automotive domain. A description of testing practice as observed in these studies is provided, confirming that testing activities are used for multiple purposes depending on the context, and are intertwined with design from start to finish of the development process, not done after it as many models depict. Descriptive process models are developed to indicate some of the key insights, and opportunities for further research are suggested

Systematic review investigating the reporting of comorbidities and medication in randomized controlled trials of people with dementia

Objectives: dementia is a debilitating condition characterised by global loss of cognitive and intellectual functioning, which reduces social and occupational performance. This population frequently presents with medical co-morbidities such as hypertension, cardiovascular disease and diabetes. The CONSORT statement outlines recommended guidance on reporting of participant characteristics in clinical trials. It is, however, unclear how much these are adhered to in trials assessing people with dementia. This paper assesses the reporting of medical co-morbidities and prescribed medications for people with dementia within randomised controlled trial (RCT) reports. Design: a systematic review of the published literature from the databases AMED, CINAHL, MEDLINE, EMBASE and the Cochrane Clinical Trial Registry from 1 January 1997 to 9 January 2014 was undertaken in order to identify RCTs detailing baseline medical co-morbidities and prescribed medications . Eligible studies were appraised using the Critical Appraisal Skills Programme (CASP) RCT appraisal tool, and descriptive statistical analyses were calculated to determine point prevalence. Results: nine trials, including 1474 people with dementia, were identified presenting medical co-morbidity data. These indicated neurological disorders ( prevalence 91%), vascular disorders (prevalence 91%), cardiac disorders ( prevalence 74%) and ischaemic cerebrovascular disease ( prevalence 53%) were most frequently seen. Conclusions: published RCTs poorly report medical co-morbidities and medications for people with dementia. Future trials should include the report of these items to allow interpretation of whether the results are generalisable to frailer older populations