Cooperative Maintenance Research Articles

DivideMerge: A multi-vessel optimization approach for cooperative operation and maintenance scheduling in offshore wind farm

The optimization of maintenance scheduling and routing in offshore wind farms is crucial for the intelligent operation and maintenance of offshore wind energy. It involves determining the optimal timing, assigning vessels, planning routes, and efficiently completing maintenance tasks with maximum efficiency and minimal cost. Traditional branch-and-bound search methods, often used in multi-vessel cooperative maintenance scheduling models, face limitations in finding optimal solutions efficiently, while classic heuristic methods may compromise on global optimality. This paper introduces DivideMerge, a high-performance hybrid algorithm that synergizes heuristic and exact algorithms to address large-scale multi-vessel cooperative maintenance scheduling challenges in offshore wind farms. Initially, a maintenance task constraint decomposition heuristic method is utilized to break down the collaborative optimization scheduling problem into individual vessel scheduling sub-problems, ensuring adherence to the constraints of the original problem. Subsequently, the CP-SAT solver is employed to sequentially solve these sub-problems rapidly. The solutions for individual vessel scheduling are then merged to form a comprehensive solution for the multi-vessel cooperative maintenance scheduling problem. Computational results validate the effectiveness and robustness of DivideMerge, demonstrating a solution speed nearly 1000 times faster than the commercial Gurobi solver, thus offering a significant advancement in the field of offshore wind farm maintenance optimization.

Supply chain demands and cooperation maintenance for resilience in manufacturing in post-COVID era - a literature review.

The pandemic period influenced the decisions of manufacturing enterprises in the area of Supply Chain (SC) solutions and the implications for the improving the cooperation maintenance (CM) between the company workers, customer and service providers. SC demands recognition and CM enable the adaptation to market and company’s environment changes. In this paper the literature analysis according to the PRISMA methodology on the changes within SC and CM in manufacturing in post-COVID era is provided. The main development trends regarding demands for SC resilience and MC were defined: firstly: sustainable development of production in terms of SC and CM risk, and secondly: SC and CM risk management in the context of its security.

Cooperation maintenance in dynamic discrete-time multicriteria games with application to bioresource management problem

We consider a dynamic, discrete-time, game model where the players use a common resource and seek to optimize different criteria. The center (referee) shares the resource available for exploitation between the competitors. To construct a multicriteria Nash equilibrium the bargaining solution is adopted. To obtain a multicriteria cooperative equilibrium, a modified bargaining scheme that guarantees the fulfillment of individual rationality conditions is applied. Two approaches to maintain cooperative behavior, namely, the cooperative incentive equilibrium and the time-consistent payoff distribution procedure, are considered. Moreover, the cooperative incentive equilibrium is constructed under the assumption that the center punishes players for deviations. A dynamic bi-criteria bioresource management problem is investigated to illustrate the solution concepts proposed.

Effects of individual strategies for resource access on collaboratively maintained irrigation infrastructure

AbstractBuilt infrastructure for water and energy supply, transportation, and other such services underpins human well‐being and socioeconomic development. A fundamental understanding of how infrastructure design and user strategies interact can guide important design decisions as well as policy formulation for ensuring long‐term infrastructure viability in conjunction with improved individual user benefits. In this work, an agent based model (ABM) is developed to study this issue for the specific case of irrigation canals. Cooperatively maintained irrigation canals serve essential roles in sustaining agriculture‐based economies in many regions. Canal system design can strongly affect benefits derived by distributed users, regional agricultural output, and the long‐term viability of the shared infrastructure itself. Here, an ABM is used to investigate how an option to use an independent water source interacts with canal design to affect canal maintenance cooperation and farmer income. The independent water source is stylized as a well that provides access to groundwater and represents a strategically robust design option; a design option that reduces the implementer's utility vulnerability to unfavorable actions by other actors. Research in other systems has demonstrated that strategically robust designs can improve both implementer utility and the probability of collaboration. The results of this research, in contrast, demonstrate that the option of individual resource access, the strategically robust design option, as represented by a well, reduces cooperative maintenance in most cases. However, wells also improve farmer income, especially for downstream farmers that are most affected by water theft.

Research on synergic Control Algorithm and Collision Avoidance of unmanned aerial vehicle Formation

The current study mainly researches the problem of leader-follower based formation cooperative maintenance of fixed-wing UAV. First, the fixed-wing UAV formation with the leader-follower structure is used as the research object, and the flight dynamics model is established; the formation synergic control law is designed for the follower and the leader in the formation, especially the follower’s control law is improved to realize the state tracking control of the follower by controlling the speed and roll Angle of UAV; as stated by the master-slave formation, the distributed topology is introduced to realize the information interaction between adjacent UAVs, and on this basis, a collision avoidance strategy has been added to prevent drones from colliding with each other in the formation. Finally, the formation control algorithm and collision avoidance strategy are simulated through data simulation, and the results prove that the UAV formation can effectively complete the formation task and avoid collisions within the formation.

Super-rational aspiration induced strategy updating helps resolve the tragedy of the commons in a cooperation system with exit rights

Avoiding the tragedy of the commons requires altruists to incur some losses to benefit the group. Although specific rules and self-enforcing agreements could help maintain the cooperation system stable, the costly recognition and free-rider problem are still questioned these two cooperation maintenance mechanisms. We here considered the situation of both exit costs and exit benefits in the asymmetric prisoner's dilemma game and introduced a super-rational aspiration induced strategy updating, where players adjust strategies in line with their payoffs and aspirations. If their payoffs reach or exceed the aspiration levels, which may be rational or super-rational, they keep their strategies. Otherwise, they imitate a local neighbor's strategy. We explored this rule in the structured and well-mixed population. The results show that super-rationality and asymmetry could together promote cooperation when exit costs exist. With exit benefit, super-rationality promotes cooperation in both structures and asymmetry only works in the well-mixed population. This suggests that the introduced strategy updating rule could sustain cooperation among egoists with exit rights.

A Blockchain enabled location-privacy preserving scheme for vehicular ad-hoc networks

n the imminent future, with the immense need for improving road safety and demand for enhancing the overall driving experience, the utility of vehicular ad-hoc networks technology (VANET) becomes well pronounced. But, the major setbacks of VANET are centralized architecture and the lack of privacy-preserving mechanisms. As it is evident, blockchain technology is gaining attention because of the features like decentralization, distributive, cooperative maintenance and non-tampering nature. This paper presents a decentralized architecture of VANET comprising blockchain technology. The proposed blockchain-based model for VANET works in four stages: blockchain network initialization, vehicle registration, pseudonym upload, and blockchain maintenance. This can efficiently solve the problems emerging in centralized architectures and helps in resolving trust issues between the entities. We propose an algorithm for protecting location privacy and providing anonymity. Experimental analysis proves that the given architecture performs better than the existing solutions.

Why do human and non-human species conceal mating? The cooperation maintenance hypothesis.

Despite considerable cultural differences, a striking uniformity is argued to exist in human preferences for concealing sexual intercourse from the sensory perception of conspecifics. However, no systematic accounts support this claim, with only limited attempts to understand the selective pressures acting on the evolution of this preference. Here, I combine cross-cultural and cross-species comparative approaches to investigate these topics. First, an analysis of more than 4572 ethnographies from 249 cultures presents systematic evidence that the preference to conceal mating is widespread across cultures. Second, I argue that current anthropological hypotheses do not sufficiently explain why habitual concealment of mating evolved in humans but is only seldom exhibited by other social species. Third, I introduce the cooperation maintenance hypothesis, which postulates that humans, and a specific category of non-human species, conceal matings to prevent sexual arousal in witnesses (proximate explanation). This allows them to simultaneously maintain mating control over their partner(s) and cooperation with group members who are prevented from mating (ultimate explanations). I conclude by presenting a comparative framework and predictions to be tested across species and human cultures.

Cooperative maintenance of cellular identity in systems with intercellular communication defects.

The cooperative dynamics of cellular populations emerging from the underlying interactions determines cellular functions and thereby their identity in tissues. Global deviations from this dynamics, on the other hand, reflect pathological conditions. However, how these conditions are stabilized from dysregulation on the level of the single entities is still unclear. Here, we tackle this question using the generic Hodgkin-Huxley type of models that describe physiological bursting dynamics of pancreatic β-cells and introduce channel dysfunction to mimic pathological silent dynamics. The probability for pathological behavior in β-cell populations is ∼100% when all cells have these defects, despite the negligible size of the silent state basin of attraction for single cells. In stark contrast, in a more realistic scenario for a mixed population, stabilization of the pathological state depends on the size of the subpopulation which acquired the defects. However, the probability to exhibit stable pathological dynamics in this case is less than 10%. These results, therefore, suggest that the physiological bursting dynamics of a population of β-cells is cooperatively maintained, even under intercellular communication defects induced by dysfunctional channels of single cells.

Dominance-related contributions to collective territory defence are adjusted according to the threat

Across diverse societies, group members benefit from the cooperative maintenance of a shared territory (a public good). How such public goods are maintained has received extensive interest, yet individual contributions to cooperative territory defence remain poorly understood. Recent theory predicts that, in groups with social hierarchies, privileged individuals will contribute most to competition with rival groups as they benefit most from defence of the territory. Here, we investigated whether dominant individuals contribute more to territory defence in a group-territorial bird in which dominants monopolize within-group reproduction: the white-browed sparrow-weaver, Plocepasser mahali. Using simulated territorial intrusions, we demonstrate that dominants contributed significantly more than subordinates to territory defence. We also found that individual contributions were adjusted according to threat: males of both social classes significantly and similarly increased their contributions to defence in response to a high threat (playback of an unfamiliar pair's duet, rather than that of a neighbouring pair), which was associated with a stronger collective response by the group. Thus, while dominants contributed most as predicted by the asymmetry in benefits, subordinates did increase contributions when they were needed most (in small groups and under greater threat). Contributions by subordinates when needed most also highlights that dominants could still benefit substantially from tolerating the presence of subordinates despite their overall lower contributions. Our results show that public goods can be maintained despite unequal contributions and highlight the potential importance of context-dependent behavioural flexibility in mitigating collective action problems.

Interorganizational Cooperation and Youth Policy: Case of Utena

The implementation of youth policy is closely connected to interorganizational cooperation between the organizations that are active in the field of youth activities. The goal of this paper is to present the results of a study wherein the factors that possibly determine cooperation between youth organizations and the local government administration in the Utena District municipality were studied. According to the studies on cooperation and organizational behavior, the factors that contribute to cooperation are the following: an uncertainty of the future, possessing mutual goals, the costs and benefits of cooperation maintenance, and the level of trust between organizations. In order to determine the exact combination of factors and how they contribute to cross-organizational cooperation, a crisp-set qualitative comparative analysis was conducted. The possible cooperation situations between the organizations that are active in the field of youth and the local government administration were the study cases. The semistructured interview method was employed in order to interview the representatives of local the government administration and organizations. The results of data analysis revealed that the most important factor for interorganizational cooperation in the field of youth policy is the level of trust between organizations in the Utena District municipality.

The Study of the Supply Chain Cooperation Mechanism Based on the “Information Economic Man Assumption”

Widely accepted social regulations are playing an important role in influencing human cooperation, which largely reduces the demand for information and helps in forming a stable cooperation partnership. Based on this, we put forward a rational and social consistent economic agent mode—The “Information Economic Man Assumption”. Taking Field Theory for reference, we established the organizational information mode and introduced the concept of capital vector. Also the capital vector of economic organization and value orientation are taken as core variables, thus we analyze the basic condition of cooperation maintenance from economic, cultural and moral factors at the same time.

自動状態診断を基とした協働型保守管理サポート方法について -ユーザー，メーカーが一体となった保守管理サポート体制の確立へ

自動状態診断を基とした協働型保守管理サポート方法について -ユーザー，メーカーが一体となった保守管理サポート体制の確立へ

Progenitor and Terminal Subsets of CD8 + T Cells Cooperate to Contain Chronic Viral Infection

Chronic infections strain the regenerative capacity of antiviral T lymphocyte populations, leading to failure in long-term immunity. The cellular and molecular events controlling this regenerative capacity, however, are unknown. We found that two distinct states of virus-specific CD8(+) T cells exist in chronically infected mice and humans. Differential expression of the T-box transcription factors T-bet and Eomesodermin (Eomes) facilitated the cooperative maintenance of the pool of antiviral CD8(+) T cells during chronic viral infection. T-bet(hi) cells displayed low intrinsic turnover but proliferated in response to persisting antigen, giving rise to Eomes(hi) terminal progeny. Genetic elimination of either subset resulted in failure to control chronic infection, which suggests that an imbalance in differentiation and renewal could underlie the collapse of immunity in humans with chronic infections.

Cooperative Markov decision processes: time consistency, greedy players satisfaction, and cooperation maintenance

We deal with multi-agent Markov decision processes (MDPs) in which cooperation among players is allowed. We find a cooperative payoff distribution procedure (MDP-CPDP) that distributes in the course of the game the payoff that players would earn in the long run game. We show under which conditions such a MDP-CPDP fulfills a time consistency property, contents greedy players, and strengthen the coalition cohesiveness throughout the game. Finally we refine the concept of Core for Cooperative MDPs.

Research on Cooperative Maintenance Decision System for Power Plant

The cooperative maintenance is carried out of China's electric power system, an important research topic, how to achieve wide-area collaboration maintenance decision is one of the forefront research tasks in the maintenance field. In order to solve the knowledge resource sharing and utilization in the plants maintenance field, on the basis of analyzing the current status and needs of the maintenance network, to achieve the object of swarm cooperative maintenance decision-making, we have established the collaborative maintenance decision system, is supported by multi-knowledge, multi-method, multi-resource, multi-information based on knowledge grid, and also have investigated the knowledge modeling approach. Resource nodes open mutually, share resource information and by the unified management and scheduling of the knowledge grid platform, coordination between each other, provide the necessary services for different power plants, manufacturers and research institutes. That is beneficial to enhancing the diagnosis standards and treatment ability of the maintenance decision system, reducing the diagnosis and maintenance costs, and improving the diagnosis efficiency.

Conservation priorities of genetic diversity in domesticated metapopulations: a study in taurine cattle breeds.

We estimated neutral diversity of 21 European cattle breeds with 105 microsatellites. Nine of them resembled unselected Balkan Buša strains with diffuse breeding barriers and the 12 others were strongly differentiated, isolated breeds. Because of the impact of neutral genetic diversity on long-term population adaptive capacity, we discuss the long-term outcome of different conservation priorities in a subdivided metapopulation of the investigated cattle breeds. The optimal contribution to a pool of total genetic diversity allocated more than 95% of long-term relevant neutral diversity to virtually unselected strains of the Balkan Buša, while the maximization of total variance preferred inbred breeds. Current artificial selection methods, such as genomic selection sped up and a recovery of underestimated traits becomes quickly impossible. We emphasize that currently neutral and even deleterious alleles might be required for future genotypes in sustainable and efficient livestock breeding and production systems of a 21st century. We provide cumulative evidences that long-term survival relies on genetic complexity and complexity relies on allelic diversity. Our results suggest that virtually unselected, nonuniform strains harbor a crucial proportion of neutral diversity and should be conserved with high global priority. As one example, we suggest a cooperative maintenance of the nondifferentiated, highly fragmented, and fast vanishing metapopulation of Balkan Buša.

Workflow specification for interaction management between experts in a cooperative remote diagnosis process

The maintenance became one of the strategic industrial functions. Far from being stabilized today, it progress by introducing the new management methods and the technological development of the production equipments, in particular in the measurement and the control operation. All these factors modify the organization modes of the maintenance function, which converges more and more towards a cooperative approach. It will absorb a big part henceforth, and subsequently, will require a rigorous modeling allowing its future implementation. In this fact, we propose the specification of a workflow model to assist the cooperative maintenance. It main aim, will be to coordinate the interactions between the various intervening actors in the maintenance process.

Relay assignment and cooperation maintenance in wireless networks: a game theoretical approach

In this study, the authors study the relays assignment problem in cooperative wireless networks with self-interested nodes. The authors propose a cooperation mechanism which includes the cooperative relationship formation stage and cooperation maintenance stage. The cooperative relationship among the nodes can be modelled as an exchange market game where nodes trade transmission power between each other to obtain diversity gain. The exchange games have a basic assumption that each node conforms to trade agreement so that each agent has the option to trade its good to obtain a better one. In such a game, strict core is considered as individual rational, Pareto optimal and relationship-stable solution. A cooperation cycle formation (CCF) algorithm is proposed to obtain the strict core solution. However, in networks, some deviated nodes may break the cooperation agreement to obtain more utility gain. Such deviated behaviours in the cooperation cycles can totally destroy the cooperation relationship. However, the data transmissions in networks have the repeated element. Hence, based on the cooperative cycle formed by CCF, the authors introduce a repeated game model for cooperation maintenance in the second stage. A dynamic punishment and recover mechanism is proposed to punish the deviated behaviours and recover cooperation.

Pro-tumorigenic Effects of miR-31 Loss in Mesothelioma

The human genome encodes several hundred microRNA (miRNA) genes that produce small (21-23n) single strand regulatory RNA molecules. Although abnormal expression of miRNAs has been linked to cancer progression, the mechanisms of this dysregulation are poorly understood. Malignant mesothelioma (MM) of pleura is an aggressive and highly lethal cancer resistant to conventional therapies. We and others previously linked loss of the 9p21.3 chromosome in MM with short time to tumor recurrence. In this study, we report that MM cell lines derived from patients with more aggressive disease fail to express miR-31, a microRNA recently linked with suppression of breast cancer metastases. We further demonstrate that this loss is due to homozygous deletion of the miR-31-encoding gene that resides in 9p21.3. Functional assessment of miR-31 activity revealed its ability to inhibit proliferation, migration, invasion, and clonogenicity of MM cells. Re-introduction of miR-31 suppressed the cell cycle and inhibited expression of multiple factors involved in cooperative maintenance of DNA replication and cell cycle progression, including pro-survival phosphatase PPP6C, which was previously associated with chemotherapy and radiation therapy resistance, and maintenance of chromosomal stability. PPP6C, whose mRNA is distinguished with three miR-31-binding sites in its 3'-untranslated region, was consistently down-regulated by miR-31 introduction and up-regulated in clinical MM specimens as compared with matched normal tissues. Taken together, our data suggest that tumor-suppressive propensity of miR-31 can be used for development of new therapies against mesothelioma and other cancers that show loss of the 9p21.3 chromosome.