Productivity and Management of Renewable Resources: Why More Efficient Fishing Fleets Should Fish Less

This article analyses the effect of productivity improvements on optimal fisheries management. It is shown that when harvest costs are independent of resource stock and the stock is below its steady state level, then for any given stock it is optimal to reduce harvest levels in response to a productivity increase unless optimal harvest rate is already zero. If harvest costs are stock dependent this result is modified; for stock dependent harvest costs there exists an interval of stock sizes below the steady state where it is optimal to reduce the harvest rate for any given stock size whereas if the harvest rate is close to an economically optimal steady state it is optimal to increase the harvest rate.

On the Estimation of the Initial Stock in the Problem of Resource Extraction

We consider a differential game of non-renewable resource extraction, in which the players do not know the precise value of the resource stock and, thus, have to make an estimate. We define the value of information about the initial stock and give recommendations for the choice of the estimate depending on the parameters of the problem. Further, we consider the situation where the players only know the bounds for the stock of the resource and solve the problem of computing the optimal estimate, such that it minimizes the players’ losses in the worst-case scenario. The analysis allows us to give a simple rule for the choice of the optimal estimate of the resource stock.

Natural Resource Management: A Network Perspective

This paper studies the role of social networks in the management of natural resources. We consider a finite number of agents who exploit a specific natural resource. Harvesting is subject to three external effects, namely resource stock externalities, crowding externalities, and collaboration spillovers. We show that the structure of the social network—defined by the presence of collaboration links between individual agents—determines the equilibrium and the optimal harvesting amount. We then allow the agents to make decisions about creating or eliminating cooperation links, which endogenizes the structure of the network and is proved to affect total harvesting and aggregate welfare. Conservation plans are shown to change the regulator’s objective and increase even further the gap between the decentralized and the optimal outcomes. We show that the optimal policy depends explicitly on the structure of the network and the ‘centrality’ of the associated agents. Finally, introducing heterogeneity is proved to affect both individual profits and the incentives to create cooperation links.

Feedback Nash Equilibrium of N Agents Fishery Problem

This paper is built on the fundamental of Jorgensen and Sorge considering a differential game about fishery problem. In reality, the exploiters can be many because of the non-excludability of common resource. Thus, we expand the former two players model to N players model and we find more different equilibriums in N players scenario. Through this, we want to find some guidance for the changing of common resource stock. Further to control overexploitation.

Storage Management and Wastage of Reproductive Health Medicines in Public Health Facilities of West Wollega Zone, Ethiopia: Mixed Study

Background: Keeping proper storage conditions at health facilities is important to reduce pharmaceutical wastage caused by environmental factors. The expiration of medicines at the health facilities led to wastage of potentially life-saving drugs and unnecessary expenditure on the disposal of those expired medicines. Therefore, the aim of this study was to assess pharmaceutical stores and wastage of reproductive health medicines due to expirationMethod: A facility-based descriptive cross-sectional quantitative and qualitative study was conducted using a checklist, structured and semi-structured questionnaires.Results: Among 23 health facilities assessed, 17 (73.91%) (4(100%) hospitals and 13(68.42%) health centers) fulfilled desirable storage conditions. The total value of reproductive health medicines wasted due to expire in surveyed facilities was 357,920.52 ETB (12,323.81 US dollars) and the Percentage of Stock Wasted due to Expiration was 8.04%. Levonorgestrel 0.75mg tablet contributed highest percentage to expired medicines.Conclusion: Pharmaceutical stores in hospitals had equipment and furniture, fulfilled desirable storage conditions, whereas, significant number of the health centers’ medical store did not comply with the recommended storage conditions. Challenges of store management identified were poor infrastructure, administrative challenges, and shortage of human resource. Stock wasted due to expiration was high and the contributing challenge was non-need-based supply. So Ethiopian pharmaceutical Supply Agency should supply reproductive health medicines based on need and concerned government bodies should avail pharmaceutical store infrastructures, hire professionals, and follow health facilities administrations.

Road to digital manufacturing – a longitudinal case-based analysis

PurposeThe authors’ main objective is to examine the resource alteration underlying the digital manufacturing transformation. The authors rely on the adaptation aspect of dynamic capabilities (DC) theory and their analysis shows how and why a factory adapts its resources and capabilities during digital transformation.Design/methodology/approachTo grasp the change, the authors apply the longitudinal case study method within a revelatory case setting. The digital transformation is detailed from the perspective of a subsidiary that has played a key role in the division's digital transformation.FindingsAnalysing the revealed four stages of the transformation through the lenses of the DC components of adaptation (sensing capability, absorptive capacity, integrative capability, relational capability), this study suggests a sequence with unbalanced characteristics. Each stage starts with sensing capability, each component appears during each stage and each stage is dominated by a different component. Relying on the path dependency concept, the authors also present that the interplay between lean as an old resource stock and digital manufacturing as a new resource stock is rather a necessity, especially at the beginning of the transformation (at a corporation that pursues lean for years).Practical implicationsDigital strategy development is rather an intermediate element of the transformation, since committed personnel (or maybe their network) start bottom-up and coordinate initiatives as they sense the opportunities in the environment. Top managers should rely on their accumulated knowledge and involve them into the transfer coalition in the top-down phase of digitalization. The authors’ case also underlines that starting to experiment with novel technologies requires a solid (and usually expensive) technological and human basis. Finally, process improvement focussed developments at a high-performing factory might be just enough to deal with ever-demanding customer expectations.Originality/valueThis study is among the firsts in operations management that relies on the DC theory to follow up the digital transformation of a factory. A further valuable contribution is that the adaptation process is examined in a longitudinal case study.

Rational taxation in an open access fishery model

We consider a model of fishery management, where n agents exploit a single population with strictly concave continuously differentiable growth function of Verhulst type. If the agent actions are coordinated and directed towards the maximization of the discounted cooperative revenue, then the biomass stabilizes at the level, defined by the well known “golden rule”. We show that for independent myopic harvesting agents such optimal (or ε-optimal) cooperative behavior can be stimulated by the proportional tax, depending on the resource stock, and equal to the marginal value function of the cooperative problem. To implement this taxation scheme we prove that the mentioned value function is strictly concave and continuously differentiable, although the instantaneous individual revenues may be neither concave nor differentiable.