The impact of nonlinear dynamics on the resilience of a grocery supply chain

Purpose of this paper: In an effort to improve operational and logistical efficiencies, UK grocery retailers combined primary and secondary distribution increasing the importance of designing resilient replenishment systems in the distribution centre. This paper has the purpose to analyse the resilience performance of the distribution centre stock ordering system within a grocery retailer. Design/methodology/approach: A system dynamics approach is used for framing and building a credible representation of the real system. Mathematical analysis of the nonlinear model based on nonlinear control engineering techniques in combination with system dynamics simulation have been used to understand the behaviour of stock and shipment output responses in the distribution centre given step and periodic demand signals. Findings: Preliminary mathematical analysis through nonlinear control theory techniques has been undertaken in order to gain initial insights in the understanding of the replenishment control model. This practice allowed the researcher to identify specific behaviour change in the DC stock and shipment responses, which are key indicators for assessing supply chain resilience, without going through a time-consuming simulation process. Transfer function analysis and describing function serve as a guideline for undertaking system dynamics simulation. Value: This paper aims to fill the gap in the literature of supply chain resilience by using quantitative system dynamics methods to assess the resilience performance of a grocery retailer. In this way, we also supplement the literature with empirical data. Moreover, we explore different analytical methods since simulation is the predominant method for quantitative analysis of system dynamics. Research limitations/implications (if applicable): This research is limited to the dynamics of single-echelon supply chain systems. Although the EPOS sales data and the store replenishment system have been considered in the validation process, this study has focused on analysing the resilience performance of the DC replenishment system only. Considering the multi-echelon supply chain is intended for further research activities. Practical implications (if applicable): The findings suggest that the distribution centre replenishment system can be re-designed in order to improve the supply chain resilience performance. The ‘As Is’ scenario produces slow response of stock levels and inventory targets are never recovered due to a permanent offset

Establishing a framework for the effective design of resilient supply chains with inherent non-linearities

Purpose of this paper: Previous control theory research on supply chain dynamics has predominantly taken a linear perspective of the real world, whereas nonlinearities have usually been studied via a simulation approach. Nonlinearities can naturally occur in supply chains through the existence of physical and economic constraints, for example, capacity limitations. Since the ability to flex capacity is an important aspect of supply chain resilience, there is a need to rigorously study such nonlinearities. Hence, the purpose of this paper is to propose a framework for the dynamic design of supply chains so that they are resilient to nonlinear system structures

Consuming the million-mile electric car

Unlike for many consumer products, there has been no strong environmental case for extending the life of internal combustion engine cars as the majority of their environmental impact is fuel consumed in use and not the energy and materials involved in manufacturing. Indeed, with improving fuel efficiency, product life extension is environmentally undesirable; older, less fuel-efficient cars need to be replaced by newer more fuel-efficient models. Electric vehicles (EVs) are predominantly considered environmentally beneficial by using an increasingly decarbonised fuel – electricity. However, LCA analyses show that EVs have substantial environmental impacts in their materials, manufacturing and disposal. The high ‘embedded’ environmental impacts of EVs fundamentally change the case for product life extension. Thus, product life extension is desirable for EVs and they are suited to it. While petrol and diesel cars have an average lifetime mileage of 124,000 miles (200,000 Kilometres), the case for the million-mile (1.6 million Kilometre) electric car appears strong. Although it may be technically possible to produce a million-mile EV, how will such vehicles be consumed given that the car consumption is complex, involving, for example, extracting use and symbolic value? In this contribution we explore the nature of the relationship between cars and the consumer that moves beyond technical and functional value to understand what form of access consumers require to an EV across its entire 50-year life. If such consumption aspects are overlooked then, even if the million-mile car is technically viable, it is unlikely to be adopted and the environmental benefits they may yield will be lost.Peer reviewedFinal Accepted Versio

Isolated Antibiotic Producing Bacteria in Local Soil Samples Determined to be Bacillus

Nosocomial pathogens are multi-drug resistant to antibiotics that fight bacterial infections posing danger to the public health, the most dangerous of them being the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.). This project is a collabortaion with the TIny Earth Project Initiative (TEPI), which is a global network of educators and students focused on studentsourcing antibiotic discovery from the soil. TEPI allows student-led research on local soil samples from Bettendorf, IA to discover potential novel antibiotic producing bacteria that could potentially treat ESKAPE pathogens and reduce public health risk. Two soil isolates were identified as antibiotic producing bacteria, CP-8-LB-B. subtilis and CP-26-TSA-B. subtilis, that worked against Bacillus subtilis. The soil isolates were sent for 16S rRNA sequencing at the University of Iowa, Institute of Human Genetics and ran through the NCBI BLAST program to be identified as belonging to the Bacillus genus

Why They Fight: Combat Motivation in the Iraq War

With the recent lightning swift combat successes of Operation IRAQI FREEDOM, there may be a tendency to view with awe the lethality of U.S. technology and training. The researchers, however, argue that the true strength of America\u27s military might lies not in its hardware or high-tech equipment, but in its soldiers. Dr. Leonard Wong and his colleagues traveled to Iraq to see what motivated soldiers to continue in battle, to face extreme danger, and to risk their lives in accomplishing the mission. As a means of comparison, they began by interviewing Iraqi Regular Army prisoners of war to examine their combat motivation and unit dynamics. The researchers then interviewed U.S. combat troops fresh from the fields of battle to examine their views. What they found was that today\u27s U.S. soldiers, much like soldiers of the past, fight for each other. Unit cohesion is alive and well in today\u27s Army. Yet, Dr. Wong and his fellow researchers also found that soldiers cited ideological reasons such as liberation, freedom, and democracy as important factors in combat motivation. Today\u27s soldiers trust each other, they trust their leaders, they trust the Army, and they also understand the moral dimensions of war. This year marks the 30th anniversary of the all-volunteer Army. This monograph is a celebration of the success of that radical idea and the transformation of the U.S. Army from a demoralized draft army, to a struggling all-volunteer force, to a truly professional Army.https://press.armywarcollege.edu/monographs/1787/thumbnail.jp

Evaluating regional emission estimates using the TRACE-P observations

Measurements obtained during the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) experiment are used in conjunction with regional modeling analysis to evaluate emission estimates for Asia. A comparison between the modeled values and the observations is one method to evaluate emissions. Based on such analysis it is concluded that the inventory performs well for the light alkanes, CO, ethyne, SO2, and NOₓ. Furthermore, based on model skill in predicting important photochemical species such as O₃, HCHO, OH, HO₂, and HNO₃, it is found that the emissions inventories are of sufficient quality to support preliminary studies of ozone production. These are important finding in light of the fact that emission estimates for many species (such as speciated NMHCs and BC) for this region have only recently been estimated and are highly uncertain. Using a classification of the measurements built upon trajectory analysis, we compare observed species distributions and ratios of species to those modeled and to ratios estimated from the emissions inventory. It is shown that this technique can reconstruct a spatial distribution of propane/benzene that looks remarkably similar to that calculated from the emissions inventory. A major discrepancy between modeled and observed behavior is found in the Yellow Sea, where modeled values are systematically underpredicted. The integrated analysis suggests that this may be related to an underestimation of emissions from the domestic sector. The emission is further tested by comparing observed and measured species ratios in identified megacity plumes. Many of the model derived ratios (e.g., BC/CO, SOₓ/C₂H₂) fall within ∼25% of those observed and all fall outside of a factor of 2.5. (See Article file for details of the abstract.)Department of Civil and Environmental EngineeringAuthor name used in this publication: Wang, T

Evaluation Process for GraPE (A Web-Based Expert System for Reviewing Grant Proposal)

A reviewing process of grant proposals is of paramount importance and tiresome for a referee. It excessively consumes time in reading and analysing the content. However, there is no exact methodology to help and assist referees in the evaluation process. The objective of this vroject is to build a web-based expert system to assist beginner referees in this process The system is based on ERA (Electronic Referee Assistant), la knowledge-based advisor for Informatics research papers, and named GraPE (Grant Proposal ERA ). GraPE aims to provide guidance to beginner referees to help them make a better review and become better reviewers. This paper will describe GraPE and the system evaluation that has been carried out in order to confirm the hypothesis proposed in this project

Overcoming barriers to engaging socio-economically disadvantaged populations in CHD primary prevention: a qualitative study

<p><b>Background:</b> Preventative medicine has become increasingly important in efforts to reduce the burden of chronic disease in industrialised countries. However, interventions that fail to recruit socio-economically representative samples may widen existing health inequalities. This paper explores the barriers and facilitators to engaging a socio-economically disadvantaged (SED) population in primary prevention for coronary heart disease (CHD).</p> <p><b>Methods:</b> The primary prevention element of Have a Heart Paisley (HaHP) offered risk screening to all eligible individuals. The programme employed two approaches to engaging with the community: a) a social marketing campaign and b) a community development project adopting primarily face-to-face canvassing. Individuals living in areas of SED were under-recruited via the social marketing approach, but successfully recruited via face-to-face canvassing. This paper reports on focus group discussions with participants, exploring their perceptions about and experiences of both approaches.</p> <p><b>Results:</b> Various reasons were identified for low uptake of risk screening amongst individuals living in areas of high SED in response to the social marketing campaign and a number of ways in which the face-to-face canvassing approach overcame these barriers were identified. These have been categorised into four main themes: (1) processes of engagement; (2) issues of understanding; (3) design of the screening service and (4) the priority accorded to screening. The most immediate barriers to recruitment were the invitation letter, which often failed to reach its target, and the general distrust of postal correspondence. In contrast, participants were positive about the face-to-face canvassing approach. Participants expressed a lack of knowledge and understanding about CHD and their risk of developing it and felt there was a lack of clarity in the information provided in the mailing in terms of the process and value of screening. In contrast, direct face-to-face contact meant that outreach workers could explain what to expect. Participants felt that the procedure for uptake of screening was demanding and inflexible, but that the drop-in sessions employed by the community development project had a major impact on recruitment and retention.</p> <p><b>Conclusion:</b> Socio-economically disadvantaged individuals can be hard-to-reach; engagement requires strategies tailored to the needs of the target population rather than a population-wide approach.</p&gt

Reconstructing ‘the Alcoholic’: Recovering from Alcohol Addiction and the Stigma this Entails

Public perception of alcohol addiction is frequently negative, whilst an important part of recovery is the construction of a positive sense of self. In order to explore how this might be achieved, we investigated how those who self-identify as in recovery from alcohol problems view themselves and their difficulties with alcohol and how they make sense of others’ responses to their addiction. Semi-structured interviews with six individuals who had been in recovery between 5 and 35 years and in contact with Alcoholics Anonymous were analysed using Interpretative Phenomenological Analysis. The participants were acutely aware of stigmatising images of ‘alcoholics’ and described having struggled with a considerable dilemma in accepting this identity themselves. However, to some extent they were able to resist stigma by conceiving of an ‘aware alcoholic self’ which was divorced from their previously unaware self and formed the basis for a new more knowing and valued identity