Metastable Features of Economic Networks and Responses to Exogenous Shocks

It has been proved that network structure plays an important role in addressing a collective behaviour. In this paper we consider a network of firms and corporations and study its metastable features in an Ising based model. In our model, we observe that if in a recession the government imposes a demand shock to stimulate the network, metastable features shape its response. Actually we find that there is a minimum bound where demand shocks with a size below it are unable to trigger the market out from recession. We then investigate the impact of network characteristics on this minimum bound. We surprisingly observe that in a Watts-Strogatz network though the minimum bound depends on the average of the degrees, when translated into the economics language, such a bound is independent of the average degrees. This bound is about $0.44 \Delta$GDP, where $\Delta$GDP is the gap of GDP between recession and expansion. We examine our suggestions for the cases of the United States and the European Union in the recent recession, and compare them with the imposed stimulations. While stimulation in the US has been above our threshold, in the EU it has been far below our threshold. Beside providing a minimum bound for a successful stimulation, our study on the metastable features suggests that in the time of crisis there is a "golden time passage" in which the minimum bound for successful stimulation can be much lower. So, our study strongly suggests stimulations to be started within this time passage.Comment: 13 pages, 10 figures, accepted for publication in PloS On

A Comparative Study on the Prohibition of Sitting and Doing Religious Services in Tombs from the Point s of View of Ibn Taymiyyah and the Four Sunni Schools

Doing religious services in tombs is one of the controversies among Ibn Taymiyyah and his followers and the Sunni Muslims. Wahhabis believe that the people doing religious services in the tombs of prophets are pagan; they demolish holy tombs, excommunicate and exterminate other Muslims.  Ibn Taymiyyah as the main theorist of excommunicative thinking justifies the excommunication based on some weak arguments like a Hadith related from Aba-Morsad Al-Ghanavi prohibiting religious service in tombs and even sometimes excommunicates the act. The present study, attempts to conduct a comparative study on the issue of doing services in tombs from the point of view of Ibn Taymiyyah and his follower and the four Sunni Schools of jurisprudence. The final conclusion made is that beside several errors in the documentation and content of the above Hadith, it conflicts with many other general and specific Hadiths allowing religious service in tombs. Moreover, Sunni scholars have antipathy toward the act in their most radical ideas and do not consider it taboo. Another important conclusion made is that the Wahhabis and Ibn Taymiyyah ideas are in great contradiction with Sunni and other Muslims' ideas. Keywords: Ibn Taymiyyah; Service; Tomb; Sunni; Prayers; Do not say prayers; Aba-Morsad Al-Ghanavi; Do not say prayers for the

The relationship between Shia and protests in sight of Madlong and Halm

The study scrutinizes the relationship between Shia and protest in the era ending in the time of Imam Asgari [Peace be upon him]. Two high-cited orientalists, Madlong and Halm, are considered in this reviewing study and it is similarly but with different deductions inferred from both that the role of Imam in social protests is confirmed. A continuous identified history is given by Madlong for Imam Shia, at least after Imam Jafar Sadegh [P.B.U.H]. He believes that Imam Jurisprudence had completely illuminated the basic concepts of this gilder (Shia) such as Imamat (pontificate) itself. He generally claims a leadership role for Imam in all the aspects of the society including protest. But Halm thinks the main identification of Imam Shia has been recognized in the beginning of the Short Occultation and not before that. Hence the relationship between Shia and protest could not be relevant to Imam Asgari or his ancestors. However, it is possible to look at the topic for all of Imams separately. Key Words: Shia, Protest, Orientalist

Empirical Coordination in a Triangular Multiterminal Network

In this paper, we investigate the problem of the empirical coordination in a triangular multiterminal network. A triangular multiterminal network consists of three terminals where two terminals observe two external i.i.d correlated sequences. The third terminal wishes to generate a sequence with desired empirical joint distribution. For this problem, we derive inner and outer bounds on the empirical coordination capacity region. It is shown that the capacity region of the degraded source network and the inner and outer bounds on the capacity region of the cascade multiterminal network can be directly obtained from our inner and outer bounds. For a cipher system, we establish key distribution over a network with a reliable terminal, using the results of the empirical coordination. As another example, the problem of rate distortion in the triangular multiterminal network is investigated in which a distributed doubly symmetric binary source is available.Comment: Accepted in ISIT 201

Context-Aware Information Retrieval for Enhanced Situation Awareness

In the coalition forces, users are increasingly challenged with the issues of information overload and correlation of information from heterogeneous sources. Users might need different pieces of information, ranging from information about a single building, to the resolution strategy of a global conflict. Sometimes, the time, location and past history of information access can also shape the information needs of users. Information systems need to help users pull together data from disparate sources according to their expressed needs (as represented by system queries), as well as less specific criteria. Information consumers have varying roles, tasks/missions, goals and agendas, knowledge and background, and personal preferences. These factors can be used to shape both the execution of user queries and the form in which retrieved information is packaged. However, full automation of this daunting information aggregation and customization task is not possible with existing approaches. In this paper we present an infrastructure for context-aware information retrieval to enhance situation awareness. The infrastructure provides each user with a customized, mission-oriented system that gives access to the right information from heterogeneous sources in the context of a particular task, plan and/or mission. The approach lays on five intertwined fundamental concepts, namely Workflow, Context, Ontology, Profile and Information Aggregation. The exploitation of this knowledge, using appropriate domain ontologies, will make it feasible to provide contextual assistance in various ways to the work performed according to a user’s taskrelevant information requirements. This paper formalizes these concepts and their interrelationships

Predicting the effects of dimensional and material stiffness variations on a compliant bistable microrelay performance

In this paper we investigate the effects of dimensional and material stiffness variations on a microrelay performance. A linear displacement bistable micromechanism is modelled by pseudo-rigid-body model method and fully characterized. To find the effects of dimensional and material stiffness variation, an analysis of mechanical error is used. The method is a stochastic one and takes into account the random nature of variations. Variations of the contact force and required power of a microrelay example is obtained by the method introduced and the performance of the microrelay is determined. The method introduced is a simple, effective and general that may be used at the design level

UNIT AND UNITARY CAYLEY GRAPHS FOR THE RING OF EISENSTEIN INTEGERS MODULO nn

Let ${E}_{n}$ be the ring of Eisenstein integers modulo $n$. We denote by $G({E}_{n})$ and $G_{{E}_{n}}$, the unit graph and the unitary Cayley graph of ${E}_{n}$, respectively. In this paper, we obtain the value of the diameter, the girth, the clique number and the chromatic number of these graphs. We also prove that for each $n>1$, the graphs $G(E_{n})$ and $G_{E_{n}}$ are Hamiltonian