Currency substitution as an automatic stabilizer

In the presence of frictions, the existing literature shows that currency substitution is detrimental for domestic aggregate stability. This paper singles out the role of currency substitution and shows that diversified currency holdings operate as an automatic stabilizer that mitigates belief-driven cyclical fluctuations in Farmer’s (1997) indeterminate monetary economy. When the foreign inflation rate is lower than the domestic inflation rate, the model’s steady state always displays saddle-path stability. Hence, equilibrium indeterminacy originally present in the domestic country is entirely removed in the presence of diversified currency holdings. When the foreign inflation rate is higher than the domestic inflation rate, then depending on the degrees of currency substitution and relative risk aversion, indeterminacy is either impossible or the requisite level of the foreign inflation rate for indeterminacy is too high to square with data. The stabilizing effect of diversified currency holdings on domestic aggregate stability is robust to whether domestic and foreign currencies display as Edgeworth substitutes or complements, or are additively separable in the household’s preferences.

Research on Distributed In-Vehicle Wireless Self-Organized Routing Protocol Distribution Mechanism

In recent years, the application of intelligent transportation systems has gradually made the transportation industry safe, efficient, and environmentally friendly and has led to a broader research prospect of vehicle wireless communication technology. Distributed vehicular self-organizing networks are mobile self-organizing networks in realistic traffic situations. Data interaction and transmission between nodes are achieved through the establishment of a vehicular self-organizing network. In this paper, a multipath routing protocol considering path stability and load balancing is proposed to address the shortcomings of existing distributed vehicular wireless self-organizing routing protocols. This protocol establishes three loop-free paths in the route discovery phase and uses the path stability parameter and load level parameter together to measure the total transmission cost. The one with the lowest total transmission cost is selected as the highest priority path for data transmission in the route selection phase, and the other two are used as alternate paths, and when the primary path breaks, the higher priority of the remaining path will continue to transmit data as the primary route. In this paper, to improve the content distribution performance of target vehicles in scenarios where communication blind zones exist between adjacent roadside units, an assisted download distribution mechanism for video-like large file content is designed in the V2V and V2I cooperative communication regime. That is, considering a two-way lane scenario, we use the same direction driving vehicles to build clusters, reverse driving vehicles to carry prefetched data, and build clusters to forward prefetched data to improve the data download volume of target vehicles in nonhot scenarios such as highways with the sparse deployment of roadside units, to meet the data volume download demand of in-vehicle users for large files and give guidance for efficient distribution of large file content in highway scenarios.

FTTCNF- Novel Approach for Fault Tolerant Topology Control in Manet

In wireless networks it is observed that as nodes move unpredictably sudden link disconnections occur during transmission. This leads to frequent path changes and multiple path discoveries which subsequently increase transmission of control packets in network. The nodes in the network simply rebroadcast the received route request (RREQ) packet if they do not have the route to the required destination. In addition to this, frequent hello messages for neighbour set construction and maintenance also increase control message count in the network causing a flooding issue. In order to mitigate these problems, the proposed Fault Tolerant Topology Control Neuro Fuzzy method (FTTCNF), incorporates measures to improve the network stability and to reduce the control packets in the network. These measure 1.reduce control message transmissions among neighbours by finding a stable path 2. neighbour node distance is computed based on the reception of a signal strength Indication (RSSI), 3. path stability is decided by the link expiry time (LET) which can be used to predict the neighbour mobility deviations. These factors, ( above mentioned distance, path stability factor PSF, and LET) are subjected to the fuzzification process to identify the fuzzy rule values and are given as input to the neuron formation stage. Final neuron value is computed for all available paths and the maximum value path is chosen for data transmission. Energy level monitoring is also applied at each node to check the node’s current energy and should it go below the energy threshold level the node by itself, joining the routing process is avoided. Simulation results have proved that the proposed method significantly reduces the routing overhead and improves the stability of path during data transmission.

An Optimal Tail Selection in Risk Measurement

The appropriate choice of a threshold level, which separates the tails of the probability distribution of a random variable from its middle part, is considered to be a very complex and challenging task. This paper provides an empirical study on various methods of the optimal tail selection in risk measurement. The results indicate which method may be useful in practice for investors and financial and regulatory institutions. Some methods that perform well in simulation studies, based on theoretical distributions, may not perform well when real data are in use. We analyze twelve methods with different parameters for forty-eight world indices using returns from the period of 2000–Q1 2020 and four sub-periods. The research objective is to compare the methods and to identify those which can be recognized as useful in risk measurement. The results suggest that only four tail selection methods, i.e., the Path Stability algorithm, the minimization of the Asymptotic Mean Squared Error approach, the automated Eyeball method with carefully selected tuning parameters and the Hall single bootstrap procedure may be useful in practical applications.

SBADR: stable and bandwidth aware dynamic routing protocol for mobile ad hoc network

Purpose Quality communication is a big challenge in mobile ad hoc networks because of a restricted environment for mobile devices, bandwidth-constrained radio connections, random mobility of connected devices, etc. High-quality communication through wireless links mainly depends on available bandwidth, link stability, energy of nodes, etc. Many researchers proposed stability and link quality methods to improve these issues, but they still require optimization. This study aims to contribute towards better quality communication in temporarily formed networks. The authors propose the stable and bandwidth aware dynamic routing (SBADR) protocol with the aim to provide an efficient, stable path with sufficient bandwidth and enough energy hold nodes for all types of quality of service (QoS) data communication. Design/methodology/approach The proposal made in this work used received signal strength from the media access control (MAC) layer to estimate the stability of the radio connection. The proposed path stability model combines the stability of the individual link to compute path stability. The amount of bandwidth available for communication at a specific time on a link is defined as the available link bandwidth that is understood as the maximum throughput of that link. Bandwidth as a QoS parameter ensures high-quality communication for every application in such a network. One other improvement, towards quality data transmission, is made by incorporating residual energies of communicating and receiving nodes in the calculation of available link bandwidth. Findings Communication quality in mobile ad hoc network (MANET) does not depend on a single parameter such as bandwidth, energy, path stability, etc. To address and enhance quality communication, this paper focused on high impact factors, such as path stability, available link bandwidth and energy of nodes. The performance of SBADR is evaluated on the network simulator and compared with that of other routing protocols, i.e. route stability based QoS routing (RSQR), route stability based ad-hoc on-demand distance vector (RSAODV) and Ad-hoc on-demand distance vector (AODV). Experimental outcomes show that SBADR significantly enhanced network performance in terms of throughput, packet delivery ratio (PDR) and normalized control overhead (NCO). Performance shows that SBADR is suitable for any application of MANET having random and high mobility. Research limitations/implications QoS in MANET is a challenging task. To achieve high-quality communication, the authors worked on multiple network parameters, i.e. path stability, available link bandwidth and energy of mobile nodes. The performance of the proposed routing protocol named SBADR is evaluated by a network simulator and compared with that of other routing protocols. Statistical analysis done on results proves significant enhancement in network performance. SBADR is suitable for applications of MANET having random and high mobility. It is also efficient for applications having a requirement of high throughput. Practical implications SBADR shows a significant enhancement in received data bytes, which are 1,709, 788 and 326 more in comparison of AODV, RSAODV and RSQR, respectively. PDR increased by 21.27%, 12.1%, 4.15%, and NCO decreased by 9.67%, 5.93%, 2.8% in comparison of AODV, RSAODV and RSQR, respectively. Social implications Outcomes show SBADR will perform better with applications of MANET such as disaster recovery, city tours, university or hospital networks, etc. SBADR is suitable for every application of MANET having random and high mobility. Originality/value This is to certify that the reported work in the paper entitled “SBADR: stable and bandwidth aware dynamic routing protocol for mobile ad hoc network” is an original one and has not been submitted for publication elsewhere. The authors further certify that proper citations to the previously reported work have been given and no data/tables/figures have been quoted verbatim from the other publications without giving due acknowledgment and without permission of the author(s).

Fuzzy Logic Based Path Stability Forecasting Scheme for Improving Data Dissemination in MANETs

Path stability of the mobile nodes in MANET plays a vital role in effective data dissemination as it depends on factors such as mobility, energy, signal strength. Several studies reveal that the prediction of path stability might provide solutions thereby routing performance can be increased. In most of the protocols route selection is based on metrics namely hop count, energy, etc. The metric namely mobility factor “MF” is used in some of the protocols. These protocols include nodes with less energy or nodes with high mobility which results in loss of path in a short period of time. Since it preserves the neighbor’s history, more control overhead and maintenance complexity exist. Hence, a new metric namely Active Interactive new Neighbor Rate (AINR) has been considered for optimum path selection. In scenarios of path loss, there is an immediate need for alternative paths for continuous data transfer. From literature it is evident that fuzzy logic is more significant in exploring different possible states under path stability determination. Hence a new prediction mechanism based on fuzzy logic has been proposed by considering the Residual Energy (RE), Hop count (Hop) and proposed metric Active Interactive new Neighbor Rate (AINR) as the factors for the prediction of the optimal path. This prediction mechanism is leveraged in MANET scenarios where alternate paths should be available on hand in situations such as battlefield and natural disaster. From the simulation, it has been proved that fuzzy logic prediction model provides better results in terms of various performance metrics such as Throughput, Packet delivery ratio, End-to-end delay, Energy consumption and routing overhead than the existing protocols.

Computing sunspot solutions to rational expectations models with timing restrictions

Rational expectations (RE) frameworks featuring informational constraints are becoming increasingly popular in macroeconomic research. A recent strand of literature has explored the analytics of RE models with informational subperiods, in which the occurrence of exogenous shocks is period-specific and decision makers condition their own choices and expectations upon a sequence of nested information sets (timing restrictions). Assuming the unrestricted (full information) RE model satisfies saddle-path stability, this paper provides (i) necessary and sufficient conditions for existence of an uncountably infinite set of linearly perturbed solutions to its restricted (informationally constrained) counterpart, and (ii) an algorithm for computing the full set of sunspot solutions when equilibrium indeterminacy occurs.