As waste from used electronic products grows steadily, manufacturers face take‐back regulations mandating its collection and proper treatment through recycling, or remanufacturing. Environmentalists ...greet such regulation with enthusiasm, but its effect on remanufacturing activity and industry competition remains unclear. We research these questions, using a stylized model with an original equipment manufacturer (OEM) facing competition from an independent remanufacturer (IR). We examine the effects of regulation on three key factors: remanufacturing levels, consumer surplus, and the OEM profit. First, we find that total OEM remanufacturing actually may decrease under high collection and/or reuse targets, meaning more stringent targets do not imply more remanufacturing. Consumer surplus and the OEM profit, meanwhile, may increase when OEM‐IR competition exists in a regulated market. Finally, through a numerical study, we investigate how total welfare changes in the collection target, what happens when the cost of collection is not linear, and what happens when IR products are valued differently by consumers.
Platform ecosystems have attracted a lot of attention as a new way of value creation and capture. In a longitudinal multi-case study, we compare the transformation efforts of two incumbents in the ...agricultural equipment industry between 2012 and 2021. We identify a set of interdependent choices incumbents make to adapt their model of value creation and capture toward a platform ecosystem. Based on an in-depth comparison, we show that incumbents' assessment of the potential of their product business may lead to distinct platform positioning – the platform as an extension of the legacy business (i.e., product-centric), or a product-independent platform. While our results indicate that both can initiate viable pathways for incumbents in their transition, we find that product-independent and product-centric positioning lead to distinct choice patterns and outcomes at the different levels of the emerging platform ecosystem.
•Incumbents' product to platform transition involves a set of interdependent choices•Incumbent choices are based on the intended role of the legacy product within the platform business•The study highlights two platform positioning strategies: product-centric and product-independent•Both strategies initiate viable transition pathways but lead to distinct choice patterns•Incumbent choices affect how new actors are attracted and how relationships with existing actors are reconfigured
The national defence industry concentrates on military, electronic, information and space technologies. In the near future, Ukraine's defence industry may become one of the most knowledge-intensive ...industrial sectors of the economy. Accordingly, the purpose of the study is to assess the capacity of Ukrainian defence enterprises to produce weapons and military equipment to ensure national security. The research aims not only to assess the problems of the defence industry under martial law but also to ensure the effective development of the defence industry sectors by identifying priority areas of funding.It was found that the current state of the Ukrainian defence industry does not meet the current realities of the time, especially in the context of Russia's full-scale invasion of Ukraine. The provision of equipment and weapons to military units is at a low level. It is found that the renewal of modern models of weapons and military equipment of the Armed Forces of Ukraine, before the full-scale invasion, was less than 1%, which in turn did not allow to compensate for the rate of ageing of existing weapons. The authors suggest ways to support the development of Ukraine's defence industry, in particular, through the creation of a Defence Industry Development Fund.The authors propose to create a Defence Industry Development Fund using public and private sources of funding not prohibited by the legislative framework of Ukraine, which will expand the capabilities of defence industry enterprises to produce weapons and military equipment. The creation of a system of multi-level continuous education in the defence industry and long-term conditions for the sustainable development of the defence industry's human resources will allow to engage in capacity building and reach a new level of support for the Armed Forces of Ukraine through the implementation of NATO standards.
•Investigate how to enhance periodic maintenance with failure & maintenance data.•Develop “predict, then optimize” model prescribing when to advance maintenance.•Visualize optimal policies as ...decision trees to aid interpretation & implementation.•Show value of customizing policies according to machine class & usage intensity.•Policies improve on those used in practice & can identify poorly performing machines.
We investigate whether historical machine failures and maintenance records may be used to derive future machine failure estimates and, in turn, prescribe advancements of scheduled preventive maintenance interventions. We model the problem using a sequential predict, then optimize approach. In our prescriptive optimization model, we use a finite horizon Markov decision process with a variable order Markov chain, in which the chain length varies depending on the time since the last preventive maintenance action was performed. The model therefore captures the dependency of a machine’s failures on both recent failures as well as preventive maintenance actions, via our prediction model. We validate our model using an original equipment manufacturer data set and obtain policies that prescribe when to deviate from the planned periodic maintenance schedule. To improve our predictions for machine failure behavior with limited to no past data, we pool our data set over different machine classes by means of a Poisson generalized linear model. We find that our policies can supplement and improve on those currently applied by 5%, on average.
•COVID-19 had negative effects on the trade of importing and exporting countries.•These effects have been insignificant since July 2020.•The harmful trade effects of COVID-19 have been accommodated ...since its first wave.•COVID-19 has had heterogenous trade effects across industries.
This study investigates how the effects of COVID-19 on international trade changed over time. To do that, we explore monthly data on worldwide trade from January to August in 2019 and 2020. Specifically, our study data include the exports of 34 countries to 173 countries. We estimated the gravity equation by employing various variables as a proxy for the COVID-19 damage. Our findings can be summarized as follows: First, regardless of our measures to quantify the COVID-19 pandemic, we found significantly negative effects of COVID-19 on the international trade of both exporting and importing countries. Second, those effects, especially the effects of COVID-19 in importing countries, tended to become insignificant since July 2020. This result implies that the harmful impacts of COVID-19 on international trade were accommodated after the first wave of the pandemic to some extent. Third, we found heterogeneous effects across industries. The negative effects on non-essential, durable products persist for a long time, whereas positive effects in industries providing medical products were observed.
Electric vehicle batteries should normally be removed from electric vehicles when their power capacity fall to 70% ~ 80% of new batteries. However, removed batteries can still be secondary used for ...other purposes, such as energy storage, before remanufacturing. To promote electric vehicle battery secondary use, this research studies a two-period battery secondary use closed-loop supply chain model consisting of a battery (re)manufacturer, a secondary user and a government. The government may provide subsidies for the secondary users to incentivize electric vehicle battery secondary use. It is found that, only when the recycled batteries' remaining power capacity is relatively high or their remanufacturing rate is relatively low, the government will consider a subsidy. In addition, under government's subsidy regulation, secondary battery users need to determine the quantities of batteries with relatively high power capacity for secondary use. Theoretically, this study enriches the research field of sustainable development of electric vehicle battery industry. Practically, this study also helps practitioners to better manage closed-loop supply chains with battery secondary use, and to enhance supply chain efficiency. Also, this study contributes to governments' regulatory decisions toward electric vehicle industries to balance economy and sustainability in society.
Intrasexually selected weapons Rico‐Guevara, Alejandro; Hurme, Kristiina J.
Biological reviews of the Cambridge Philosophical Society,
February 2019, Volume:
94, Issue:
1
Journal Article
Peer reviewed
Open access
ABSTRACT
We propose a practical concept that distinguishes the particular kind of weaponry that has evolved to be used in combat between individuals of the same species and sex, which we term ...intrasexually selected weapons (ISWs). We present a treatise of ISWs in nature, aiming to understand their distinction and evolution from other secondary sex traits, including from ‘sexually selected weapons’, and from sexually dimorphic and monomorphic weaponry. We focus on the subset of secondary sex traits that are the result of same‐sex combat, defined here as ISWs, provide not previously reported evolutionary patterns, and offer hypotheses to answer questions such as: why have only some species evolved weapons to fight for the opposite sex or breeding resources? We examined traits that seem to have evolved as ISWs in the entire animal phylogeny, restricting the classification of ISW to traits that are only present or enlarged in adults of one of the sexes, and are used as weapons during intrasexual fights. Because of the absence of behavioural data and, in many cases, lack of sexually discriminated series from juveniles to adults, we exclude the fossil record from this review. We merge morphological, ontogenetic, and behavioural information, and for the first time thoroughly review the tree of life to identify separate evolution of ISWs. We found that ISWs are only found in bilateral animals, appearing independently in nematodes, various groups of arthropods, and vertebrates. Our review sets a reference point to explore other taxa that we identify with potential ISWs for which behavioural or morphological studies are warranted. We establish that most ISWs come in pairs, are located in or near the head, are endo‐ or exoskeletal modifications, are overdeveloped structures compared with those found in females, are modified feeding structures and/or locomotor appendages, are most common in terrestrial taxa, are frequently used to guard females, territories, or both, and are also used in signalling displays to deter rivals and/or attract females. We also found that most taxa lack ISWs, that females of only a few species possess better‐developed weapons than males, that the cases of independent evolution of ISWs are not evenly distributed across the phylogeny, and that animals possessing the most developed ISWs have non‐hunting habits (e.g. herbivores) or are faunivores that prey on very small prey relative to their body size (e.g. insectivores). Bringing together perspectives from studies on a variety of taxa, we conceptualize that there are five ways in which a sexually dimorphic trait, apart from the primary sex traits, can be fixed: sexual selection, fecundity selection, parental role division, differential niche occupation between the sexes, and interference competition. We discuss these trends and the factors involved in the evolution of intrasexually selected weaponry in nature.
•Coopetition between original equipment manufacturer (OEM) and its supplier.•Process improvement in component production affects coopetition equilibrium.•Without process improvement, coopetition ...never occurs.•Coopetition occurs when the supplier-initiated process improvement is efficient.•With OEM-initiated process improvement, coopetition never happens.
Coopetition is a business phenomenon that dominates many supply chains. We aim to understand why and how coopetition occurs in supply chains with the presence of process improvement in upstream component production. An original equipment manufacturer (OEM) can purchase the component from either a non-competing supplier (NS) or a competing supplier (CS) that also sells substitutable products in the end consumer market. We demonstrate that without process improvement, coopetition does not exist, because the OEM prefers sourcing from the NS, even though the CS is willing to sell the component to the OEM. Two cases are considered in which process improvement is present: supplier-initiated investment, where the suppliers conduct self-investment, and OEM-initiated investment, where the OEM invests in the supplier's process. We find that with supplier-initiated investment, the CS always prefers coopetition, but the OEM may not. When the investment is efficient, coopetition occurs as an equilibrium outcome; otherwise, competition occurs. The cause of coopetition equilibrium comes from variable process improvement incentives of the CS that derive from two driving forces: the vertical wholesale price effect and the horizontal quantity competition effect. When the degree of product substitution is low, the CS increases its investment and lowers its wholesale price, benefiting the OEM. When the degree of product substitution is high, the CS reduces its investment as well as production quantity, which also benefits the OEM. Interestingly, with OEM-initiated investment, the CS might not always choose to sell the component to the OEM, and as a result, coopetition never occurs.
•Multi-stage stochastic epidemics-ventilator-logistics compartmental model.•Optimize ventilator allocation under asymptomatic uncertainty and risk.•Epidemiological, population, migration, and cost ...data-driven model.•New region-based sub-problem and bounds improving optimality gap.•A general model that could be extended to other infectious diseases.
This study presents a new risk-averse multi-stage stochastic epidemics-ventilator-logistics compartmental model to address the resource allocation challenges of mitigating COVID-19. This epidemiological logistics model involves the uncertainty of untested asymptomatic infections and incorporates short-term human migration. Disease transmission is also forecasted through a new formulation of transmission rates that evolve over space and time with respect to various non-pharmaceutical interventions, such as wearing masks, social distancing, and lockdown. The proposed multi-stage stochastic model overviews different scenarios on the number of asymptomatic individuals while optimizing the distribution of resources, such as ventilators, to minimize the total expected number of newly infected and deceased people. The Conditional Value at Risk (CVaR) is also incorporated into the multi-stage mean-risk model to allow for a trade-off between the weighted expected loss due to the outbreak and the expected risks associated with experiencing disastrous pandemic scenarios. We apply our multi-stage mean-risk epidemics-ventilator-logistics model to the case of controlling COVID-19 in highly-impacted counties of New York and New Jersey. We calibrate, validate, and test our model using actual infection, population, and migration data. We also define a new region-based sub-problem and bounds on the problem and then show their computational benefits in terms of the optimality and relaxation gaps. The computational results indicate that short-term migration influences the transmission of the disease significantly. The optimal number of ventilators allocated to each region depends on various factors, including the number of initial infections, disease transmission rates, initial ICU capacity, the population of a geographical location, and the availability of ventilator supply. Our data-driven modeling framework can be adapted to study the disease transmission dynamics and logistics of other similar epidemics and pandemics.
Sexually selected weapons, such as the antlers of deer, claws of crabs, and tusks of beaked whales, are strikingly diverse across taxa and even within groups of closely related species. Phylogenetic ...comparative studies have typically taken a simplified approach to investigate the evolution of weapon diversity, examining the gains and losses of entire weapons, major shifts in size or type, or changes in location. Less understood is how individual weapon components evolve and assemble into a complete weapon. We addressed this question by examining weapon evolution in the diverse, multi-component hind-leg and body weapons of leaf-footed bugs, superfamily Coreoidea (Hemiptera: Heteroptera). Male leaf-footed bugs use their morphological weapons to fight for access to mating territories. We used a large multilocus dataset comprised of ultraconserved element loci for 248 species and inferred evolutionary transitions among component states using ancestral state estimation. Our results suggest that weapons added components over time with some evidence of a cyclical evolutionary pattern-gains of components followed by losses and then gains again. Furthermore, our best estimate indicated that certain trait combinations evolved repeatedly across the phylogeny, suggesting that they function together in battle or that they are genetically correlated. This work reveals the remarkable and dynamic evolution of weapon form in the leaf-footed bugs and provides insights into weapon assembly and disassembly over evolutionary time.
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