scholarly journals Reorganizing Complex Network to Improve Large-Scale Multiagent Teamwork

2014 ◽  
Vol 2014 ◽  
pp. 1-12
Author(s):  
Yang Xu ◽  
Pengfei Liu ◽  
Xiang Li

Large-scale multiagent teamwork has been popular in various domains. Similar to human society infrastructure, agents only coordinate with some of the others, with a peer-to-peer complex network structure. Their organization has been proven as a key factor to influence their performance. To expedite team performance, we have analyzed that there are three key factors. First, complex network effects may be able to promote team performance. Second, coordination interactions coming from their sources are always trying to be routed to capable agents. Although they could be transferred across the network via different paths, their sources and sinks depend on the intrinsic nature of the team which is irrelevant to the network connections. In addition, the agents involved in the same plan often form a subteam and communicate with each other more frequently. Therefore, if the interactions between agents can be statistically recorded, we are able to set up an integrated network adjustment algorithm by combining the three key factors. Based on our abstracted teamwork simulations and the coordination statistics, we implemented the adaptive reorganization algorithm. The experimental results briefly support our design that the reorganized network is more capable of coordinating heterogeneous agents.

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Yang Xu ◽  
Pengfei Liu ◽  
Xiang Li ◽  
Wei Ren

Building efficient distributed coordination algorithms is critical for the large scale multiagent system design, and the communication network has been shown as a key factor to influence system performance even under the same coordination protocol. Although many distributed algorithm designs have been proved to be feasible to build their functions in the large scale multiagent systems as claimed, the performances may not be stable if the multiagent networks were organized with different complex network topologies. For example, if the network was recovered from the broken links or disfunction nodes, the network topology might have been shifted. Therefore, their influences on the overall multiagent system performance are unknown. In this paper, we have made an initial effort to find how a standard network recovery policy, MPLS algorithm, may change the network topology of the multiagent system in terms of network congestion. We have established that when the multiagent system is organized as different network topologies according to different complex network attributes, the network shifts in different ways. Those interesting discoveries are helpful to predict how complex network attributes influence on system performance and in turn are useful for new algorithm designs that make a good use of those attributes.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Enys Mones ◽  
Piotr Sapieżyński ◽  
Simon Thordal ◽  
Henrik Palmer Olsen ◽  
Sune Lehmann

AbstractAs courts strive to simultaneously remain self-consistent and adapt to new legal challenges, a complex network of of citations between decided cases is established. Using network science methods to analyze the underlying patterns of citations between cases can help us understand the large-scale mechanisms which shape the judicial system. Here, we use the case-to-case citation structure of the Court of Justice of the European Union to examine this question. Using a link-prediction model, we show that over time the complex network of citations evolves in a way which improves our ability to predict new citations. Investigating the factors which enable prediction over time, we find that the content of the case documents plays a decreasing role, whereas both the predictive power and significance of the citation network structure itself show a consistent increase over time. Finally, our analysis enables us to validate existing citations and recommend potential citations for future cases within the court.


2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 9-10
Author(s):  
George Foxcroft ◽  
Jenny Patterson

Abstract Recently published research on gilt development using contemporary commercial dam-lines has confirmed: 1) That the growth performance of gilts is rarely below the lifetime growth rate of 0.55 kg.d that would limit the onset of sexual maturity; 2) The majority of gilts provided direct daily contact with mature boars from 160 days of age reach puberty by 200 days of age and represent a normal distribution of “early responders”; 3) Gilts that respond later to boar stimulation have poorer lifetime fertility and tend to be over weight at breeding; 4) Pubertal responses to direct boar contact are significantly higher than responses to fenceline contact with boars; 5) Even if pubertal responses to direct boar contact are delayed in particular cohorts of gilts, good pubertal responses to exogenous, low-dose eCG/hCG treatments (PG600) allow efficient replacement gilt flows to be maintained in most commercial situations; 6) Delaying breeding until second observed estrus, and providing at least 10 days of acclimation to individual stall accommodation, maximizes first litter performance. When gilts were managed in purpose designed facilities that allowed daily records of vulval and behavioral responses to effective boar stimuli to be recorded, the lifetime reproductive performance of know pubertal gilts entering the breeding herd exceeded industry benchmarks. Of 2,374 naturally cyclic and 741 PG600-induced gilts delivered to the breeding herd, 97.6 and 95.7%, respectively, were bred, 94.7 and 92.0%, respectively, farrowed a first litter and 70.6 and 65.3%, respectively, farrowed a fourth litter. In terms of key factors other than reproductive performance that affect retention rate, another recent large-scale study of commercial replacement gilts derived from multiplication sows with a known litter birth weight phenotype confirmed data based on individual gilt birth weight, in that high growth rates linked to heavy weights at breeding were a major risk factor for early removal from the breeding herd. Therefore, poor gilt management must still be viewed as a major factor limiting breeding herd performance.


Author(s):  
Ron Harris

Before the seventeenth century, trade across Eurasia was mostly conducted in short segments along the Silk Route and Indian Ocean. Business was organized in family firms, merchant networks, and state-owned enterprises, and dominated by Chinese, Indian, and Arabic traders. However, around 1600 the first two joint-stock corporations, the English and Dutch East India Companies, were established. This book tells the story of overland and maritime trade without Europeans, of European Cape Route trade without corporations, and of how new, large-scale, and impersonal organizations arose in Europe to control long-distance trade for more than three centuries. It shows that by 1700, the scene and methods for global trade had dramatically changed: Dutch and English merchants shepherded goods directly from China and India to northwestern Europe. To understand this transformation, the book compares the organizational forms used in four major regions: China, India, the Middle East, and Western Europe. The English and Dutch were the last to leap into Eurasian trade, and they innovated in order to compete. They raised capital from passive investors through impersonal stock markets and their joint-stock corporations deployed more capital, ships, and agents to deliver goods from their origins to consumers. The book explores the history behind a cornerstone of the modern economy, and how this organizational revolution contributed to the formation of global trade and the creation of the business corporation as a key factor in Europe's economic rise.


2019 ◽  
Vol 14 (3) ◽  
pp. 33
Author(s):  
L. V. Tomin

The article is devoted to the analysis of the structure, the peculiarities of functioning and the socio-economic and political effects of the «platform capitalism». The basis of this model is the network effects produced by the integrated information and communication infrastructure, which contribute to the monopolization and the constant expansion of platform companies into new areas. The principle of functioning of this infrastructure is the continuous collection and further monetization of data extracted from the interactions of individuals among themselves or with one of the elements of a digitalized economy or government structures. Such an infrastructure — forms a potential threat of strengthening state and corporate control over citizens. In addition, the activities of platform companies produce negative effects on the labor market, reinforcing the process of precarization of employment. The integrated information and communication infrastructure of platform companies form a system of a kind of «digital Taylorism», which deprives the employee of autonomy and privacy in the workplace. The influence of digitalization, subjected to the technocratic logic of the neoliberal model of governance in democratic countries, strengthens the de-politicization of relations between the citizen and the state and further changes the balance of power between labor and capital in favor of the latter. Large-scale protests of the last years against the companies of “capitalism of platforms” demonstrated the structural contradictions of this model and formed new forms of organization and actions of grassroots workers of the “digital economy”.


Author(s):  
Ekaterina Bourova-Flin ◽  
Samira Derakhshan ◽  
Afsaneh Goudarzi ◽  
Tao Wang ◽  
Anne-Laure Vitte ◽  
...  

Abstract Background Large-scale genetic and epigenetic deregulations enable cancer cells to ectopically activate tissue-specific expression programmes. A specifically designed strategy was applied to oral squamous cell carcinomas (OSCC) in order to detect ectopic gene activations and develop a prognostic stratification test. Methods A dedicated original prognosis biomarker discovery approach was implemented using genome-wide transcriptomic data of OSCC, including training and validation cohorts. Abnormal expressions of silent genes were systematically detected, correlated with survival probabilities and evaluated as predictive biomarkers. The resulting stratification test was confirmed in an independent cohort using immunohistochemistry. Results A specific gene expression signature, including a combination of three genes, AREG, CCNA1 and DDX20, was found associated with high-risk OSCC in univariate and multivariate analyses. It was translated into an immunohistochemistry-based test, which successfully stratified patients of our own independent cohort. Discussion The exploration of the whole gene expression profile characterising aggressive OSCC tumours highlights their enhanced proliferative and poorly differentiated intrinsic nature. Experimental targeting of CCNA1 in OSCC cells is associated with a shift of transcriptomic signature towards the less aggressive form of OSCC, suggesting that CCNA1 could be a good target for therapeutic approaches.


Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 474
Author(s):  
Huaqiao Liu ◽  
Yiren Pan ◽  
Huiguang Bian ◽  
Chuansheng Wang

In this study, the two key factors affecting the thermal performance of the insert rubber and stress distribution on the tire sidewall were analyzed extensively through various performance tests and simulations to promote the development of run-flat tires. Four compounds and two structures of insert rubber were designed to investigate the effects of heat accumulation and stress distribution on durability testing at zero pressure. It was concluded that the rigidity and tensile strength of the compound were negatively correlated with temperature. The deformation was a key factor that affects energy loss, which could not be judged solely by the loss factor. The stress distribution, however, should be considered in order to avoid early damage of the tire caused by stress concentration. On the whole, the careful balance of mechanical strength, energy loss, and structural rigidity was the key to the optimal development of run-flat tires. More importantly, the successful implementation of the simulations in the study provided important and useful guidance for run-flat tire development.


2021 ◽  
Author(s):  
Hassan Ahmadian ◽  
Payam Mohseni

Abstract Iran's strategy with respect to Saudi Arabia is a key factor in the complex balance of power of the Middle East as the Iranian–Saudi rivalry impacts the dynamics of peace and conflict across the region from Yemen to Syria, Lebanon, Iraq and Bahrain. What is Iranian strategic thinking on Saudi Arabia? And what have been the key factors driving the evolution of Iranian strategy towards the Kingdom? In what marks a substantive shift from its previous detente policy, we argue that Tehran has developed a new containment strategy in response to the perceived threat posed by an increasingly prox-active Saudi Arabia in the post-Arab Spring period. Incorporating rich fieldwork and interviews in the Middle East, this article delineates the theoretical contours of Iranian containment and contextualizes it within the framework of the Persian Gulf security architecture, demonstrating how rational geopolitical decision-making factors based on a containment strategy, rather than the primacy of sectarianism or domestic political orientations, shape Iran's Saudi strategy. Accordingly, the article traces Iranian strategic decision-making towards the Kingdom since the Islamic Revolution of 1979 and examines three cases of Iran's current use of containment against Saudi Arabia in Syria, Yemen and Qatar.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yanlu Xing ◽  
Joël Brugger ◽  
Barbara Etschmann ◽  
Andrew G. Tomkins ◽  
Andrew J. Frierdich ◽  
...  

AbstractReaction-induced porosity is a key factor enabling protracted fluid-rock interactions in the Earth’s crust, promoting large-scale mineralogical changes during diagenesis, metamorphism, and ore formation. Here, we show experimentally that the presence of trace amounts of dissolved cerium increases the porosity of hematite (Fe2O3) formed via fluid-induced, redox-independent replacement of magnetite (Fe3O4), thereby increasing the efficiency of coupled magnetite replacement, fluid flow, and element mass transfer. Cerium acts as a catalyst affecting the nucleation and growth of hematite by modifying the Fe2+(aq)/Fe3+(aq) ratio at the reaction interface. Our results demonstrate that trace elements can enhance fluid-mediated mineral replacement reactions, ultimately controlling the kinetics, texture, and composition of fluid-mineral systems. Applied to some of the world’s most valuable orebodies, these results provide new insights into how early formation of extensive magnetite alteration may have preconditioned these ore systems for later enhanced metal accumulation, contributing to their sizes and metal endowment.


Atmosphere ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 93
Author(s):  
Andrew Hazelton ◽  
Ghassan J. Alaka ◽  
Levi Cowan ◽  
Michael Fischer ◽  
Sundararaman Gopalakrishnan

The early stages of a tropical cyclone can be a challenge to forecast, as a storm consolidates and begins to grow based on the local and environmental conditions. A high-resolution ensemble of the Hurricane Analysis and Forecast System (HAFS) is used to study the early intensification of Hurricane Dorian, a catastrophic 2019 storm in which the early period proved challenging for forecasters. There was a clear connection in the ensemble between early storm track and intensity: stronger members moved more northeast initially, although this result did not have much impact on the long-term track. The ensemble results show several key factors determining the early evolution of Dorian. Large-scale divergence northeast of the tropical cyclone (TC) appeared to favor intensification, and this structure was present at model initialization. There was also greater moisture northeast of the TC for stronger members at initialization, favoring more intensification and downshear development of the circulation as these members evolved. This study highlights the complex interplay between synoptic and storm scale processes in the development and intensification of early-stage tropical cyclones.


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