Cooperative Pushing Research Articles

An exactly solvable model for RNA polymerase during the elongation stage

We consider a Markovian model for the kinetics of RNA Polymerase (RNAP) which provides a physical explanation for the phenomenon of cooperative pushing during transcription elongation observed in biochemical experiments onEscherichia coliand yeast RNAP. To study how backtracking of RNAP affects cooperative pushing we incorporate into this model backward (upstream) RNAP moves. With a rigorous mathematical treatment of the model we derive conditions on the mutual static and kinetic interactions between RNAP under which backtracking preserves cooperative pushing. This is achieved by exact computation of several key properties in the steady state of this model, including the distribution of headway between two RNAP along the DNA template and the average RNAP velocity and flux.

Data-Driven Strategies in the Evolutionary Game of Green Port Construction: Analyzing Policy Incentives for Shore Power Adoption

This study addresses the critical challenge of green port construction in China, with a focus on the underutilized potential of shore power technology, through a computational lens. By establishing an evolutionary game model that captures the intricate dynamics among ports, shipping companies, and government agencies, we introduce a computational framework that utilizes advanced data analytics, network simulations, and optimization algorithms to evaluate policy incentives and their efficacy. The heart of our analysis lies in the deployment of network simulation tools and predictive analytics, which facilitate a deep dive into the operational dynamics and strategy adaptations within the tripartite system. Our findings underscore the pivotal role of government subsidies, quantitatively determined through optimization algorithms, in influencing the evolutionary path towards sustainable port operations. The research demonstrates that a carefully calibrated subsidy regime, informed by simulation outcomes and data-driven insights, can significantly boost the adoption of shore power technologies among ports and shipping companies, nurturing a symbiotic relationship that accelerates green construction efforts. Furthermore, the study leverages computational algorithms to simulate initial game scenarios, revealing how the presence of shore power infrastructure and technology-ready ships can catalyze a cooperative push towards environmental goals. Through a comprehensive computational approach, including the use of mathematical modeling and the analysis of vast datasets, the paper highlights the transformative power of policy interventions guided by computational intelligence. The conclusions drawn not only emphasize the necessity for targeted government action but also showcase the potential of computer science methodologies in crafting and implementing effective environmental policies, offering a novel pathway to expedite the green transformation of China’s maritime infrastructure.

Load Pushing Capacity Analysis of Individual and Multi-Cooperative Mobile Robot through Symbiotic Application

Certain missions require multiple mobile robots working together to accomplish it. There is a need, however, to determine the optimal configuration of modular mobile robots doing cooperative tasks to ensure high utilization and efficiency rate of the individual robot. This study proposed the use of a biosystem-inspired approach in assessing the influence of multiple robots on each other in performing a cooperative pushing task. The kinematics of pushing interaction at a single contact point was first discussed in the study to provide a solid foundation of the mission to be analyzed. Various dimensions in an experimental setup were also covered to better understand how these contribute to planar pushing. Through the resulting symbiotic coefficient, the study was able to determine the optimal configuration among the two, four, and six wheeled mobile robots pushing an object with various loads. While the dominant coefficient for symbiotic relationship was classified as beneficial and only one was neutral, the decline in coefficient values of the 3rd configuration (six wheeled) with respect to the 2nd configuration (4 wheeled) implies possible negative coefficient in the next configuration (8 wheeled). The maximum level of distance at which an object can be pushed was also obtained. This was called the state of plateau wherein adding another module is no longer suggested as it will not improve the pushing capacity any further. Knowing these key points significantly helps in ensuring cost and work efficiency of a given configuration in performing different missions.

RNA Polymerase interactions and elongation rate

We show that non-steric molecular interactions between RNA polymerase (RNAP) motors that move simultaneously on the same DNA track determine strongly the kinetics of transcription elongation. With a focus on the role of collisions and cooperation, we introduce a stochastic model that allows for the exact analytical computation of the stationary properties of transcription elongation as a function of RNAP density, their interaction strength, nucleoside triphosphate concentration, and rate of pyrophosphate release. Cooperative pushing, i.e., an enhancement of the average RNAP velocity and elongation rate, arises due to stochastic pushing which cannot be explained by steric hindrance alone. The cooperative effect requires a molecular repulsion in excess of a critical strength and disappears beyond a critical RNAP density, above which jamming due to collisions takes over. For strong repulsion and at the same time strong stochastic blocking, cooperative pushing at low RNAP densities is suppressed, but a reentrance regime at higher densities appears.

Third-Order Nonlinear Optical Properties of Asymmetric Non-Alternant Open-Shell Condensed-Ring Hydrocarbons: Effects of Diradical Character, Asymmetricity, and Exchange Interaction

Using spin-unrestricted density functional theory, the longitudinal static second hyperpolarizability γ has been investigated for an asymmetric azulene-like open-shell condensed-ring molecule (1) as well as for its symmetric almost closed-shell and open-shell analogues (pentacene (2) and its dicyclopenta- (3) and dicyclohepta-fused (4) analogues). It is found that the symmetric systems, 3 and 4, having intermediate diradical characters show a 6–9 times enhancement of γ as compared to 2, but that this enhancement is even larger (by a factor of 30) for the asymmetric diradicaloid, 1. Geometrical, electronic, and magnetic descriptors have shown that in 1 the terminal seven- and five-membered rings display a cooperative push–pull effect, leading to a large dipole moment, that seems to reinforce its aromaticity as well as its ionic character, whereas 3 and 4 are mostly neutral diradicaloids and are less aromatic. These features have been rationalized by resorting to an asymmetric two-site model within the vale...

Object Conveyance Algorithm for Multiple Mobile Robots based on Object Shape and Size

This paper describes a determination method of a number of a team for multiple mobile robot object conveyance. The number of robot on multiple mobile robot systems is the factor of complexity on robots formation and motion control. In our previous research, we verified the use of the complex-valued neural network for controlling multiple mobile robots in object conveyance problem. Though it is a significant issue to develop effective determination team member for multiple mobile robot object conveyance, few studies have been done on it. Therefore, we propose an algorithm for determining the number of the team member on multiple mobile robot object conveyance with grasping push. The team member is determined based on object weight to obtain appropriate formation. First, the object shape and size measurement is carried out by a surveyor robot that approaches and surrounds the object. During surrounding the object, the surveyor robot measures its distance to the object and records for estimating the object shape and size. Since the object shape and size are estimated, the surveyor robot makes initial push position on the estimated push point and calls additional robots for cooperative push. The algorithm is validated in several computer simulations with varying object shape and size. As a result, the proposed algorithm is promising for minimizing the number of the robot on multiple mobile robot object conveyance.

2P1-V10 モード切り替えを行う複数移動ロボットのモンテカルロ法を用いた協調押し動作の動作計画

2P1-V10 モード切り替えを行う複数移動ロボットのモンテカルロ法を用いた協調押し動作の動作計画

Efficient and adaptive web replication using content clustering

Recently, there has been an increasing deployment of content distribution networks (CDNs) that offer hosting services to Web content providers. In this paper, we first compare the uncooperative pulling of Web contents used by commercial CDNs with the cooperative pushing. Our results show that the latter can achieve comparable users' perceived performance with only 4%-5% of replication and update traffic compared with the former scheme. Therefore, we explore how to efficiently push content to CDN nodes. Using trace-driven simulation, we show that replicating content in units of URLs can yield 60%-70% reduction in clients' latency, compared with replicating in units of Websites. However, it is very expensive to perform such a fine-grained replication. To address this issue, we propose to replicate content in units of clusters, each containing objects which are likely to be requested by clients that are topologically close. To this end, we describe three clustering techniques and use various topologies and several large Web server traces to evaluate their performance. Our results show that the cluster-based replication achieves performance close to that of the URL-based scheme, but only at 1%-2% of computation and management cost. In addition, by adjusting the number of clusters, we can smoothly trade off management and computation cost for better client performance. To adapt to changes in users' access patterns, we also explore incremental clustering that adaptively adds new documents to the existing content clusters. We examine both offline and online incremental clustering, where the former assumes access history is available while the latter predicts access pattern based on the hyperlink structure. Our results show that the offline clustering yields performance close to that of the complete re-clustering at much lower overhead. The online incremental clustering and replication cut down the retrieval cost by 4.6 times compared with random and by 8 times compared with no replication. Therefore it is especially useful to improve document availability during flash crowds.

Introducing “Cooperative Push”: How Inefficient Environmental Policy (Sometimes!) Protects the Global Commons Better

In this paper we argue that the incentive structures of the gamesnations play in international environmental negotiations dependupon the choice of environmental policy instruments. Bargainingon the use of some instrument (e.g. an effluent charge) mayput the players into a dilemma game (like Chicken). Negotiationsto apply a different instrument (say, an emission reductionquota) may lead to a cooperation game (like Stag Hunt). The higherthe incentive to cooperate in the type of game which is built upby a specific instrument, the higher is this instrument's``cooperative push''. Of course, comparing two instruments,the one with the higher cooperative push might well be the lessefficient one. In this Paper, we analyse a situation where thehigher cooperative push of an instrument overcompensates thisinstrument's lower efficiency: Aggregate welfare withbilateral cooperation (the equilibrium of Stag Hunt) is higher than withunilateral cooperation (the equilibrium of the Chicken game).The question remains whether sovereign countries decide to playStag Hunt ending up in the welfare superior equilibrium. It isshown below that they do not in an uncoordinated optimising setting.However, we develop a particular frame where the proposedsolution meets the criteria of individual rationality,stability and fairness. It thereby establishes the politically mostdesired result – international cooperation.

Anatomy of a long boom provoking a dynamic economy in the 21st century

The world stands on the threshold of a tantalizing opportunity: the possibility of a sustained economic boom over the first decades of the next millennium. This article outlines the confluence of forces – particularly the transition to a knowledge society, the emergence of a global economy and the pursuit of environmental sustainability – which could come together to propel huge improvements in wealth‐creating capacity and wellbeing world‐wide. The transition to a knowledge economy and society over the next few decades opens up the possibility of massive productivity gains. Equally significant, stimulus for a long boom could emerge from the creation of much more deeply integrated global markets for goods, services, capital and technology. Finally, the long boom could be sustained by a cooperative push to redirect the path of humanity’s relationship to the environment – a change entailing massive investments in new, less resource‐intensive patterns of consumption and methods of production. The unleashing of these dynamic forces hinges on two basic policy thrusts. First, economic dynamism in general and a long boom in particular will demand exceptional efforts – nationally and internationally – to encourage continuous innovation and high levels of investment. Second, with the prospects for a long boom contingent on the realization of a leap in the levels of international cooperation, decision makers will have to consider bold new approaches to negotiating and reconciling conflicting interests and divergent needs.