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This work presents a dynamic posture tracking control strategy for wheel-legged systems on uneven surfaces. Based on the kinematic model of a wheel-legged robotic system, the expected positions for the end-effectors of wheel-legs are calculated according to posture references and sensor feedback. The position control problem for a general wheel-leg is investigated for the active mechanism to imitate a passive suspension and respond to the external contact forces. The position tracking accuracy of the wheel-leg is sacrificed to enhance the compliance performance under rough terrain. Because of the unique contact state with the uneven ground for each wheel-leg, the position responses are different. As a result, the forces from the wheel-legs to the fuselage are inconsistent, which leads to the risk of posture oscillations. Equipping the wheel-legs with an undirected communication network, a consensus scheme for the robotic system is developed with proven global asymptotic stability to improve the posture tracking property. A novel robotic system is established with Stewart-structured wheel-legs, which are connected by a user datagram protocol network. Comparative experimental results are carried out on the physical prototype to validate the effectiveness of the proposed approach. • An improved kinematic model avoiding geomagnetism disturbances is established for general wheel-legged robotic systems. Considering the contact forces, an active suspension controller is proposed for the single wheel-leg to track the desired position with expected compliance behaviors. • Based on an undirected communication topology, a consensus strategy is carried out for multiple ASCs. The CASC fulfills the coordination requirements and active suspension response demands with proved convergency property. • The proposed posture control scheme is applied to a wheel-legged physical prototype. The comparative experimental results between the proposed CASC and our previous studies are presented, which highlights the CASC in posture tracking accuracy and wheel-leg coordination performances. [ABSTRACT FROM AUTHOR]

Intra-urban inequality is not strictly defined and therefore cannot be measured accurately. The literature shows that the measurement of inequality varies depending on the judgment of the experts and that this judgment can be realized in several ways. Taking this into account, the capabilities created using fuzzy set theory and consensus schemes can be useful in the process of measuring inequality. The objective of their use is twofold. First, analyze the degree to which experts diverge on an ill-defined phenomenon such as inequality. Second, build a fuzzy set based Intra-Urban Inequality Indicator (F-II-I). The results of the present research show that F-II-I is adequate to represent the intra-urban inequality. The experts involved agree 93% on the weight of the inequality variables. The correlation coefficient and the proportion of outliers between the F-II-I and the Average Monthly Income per Household is 0.61 and 0.06, respectively. The degree of uncertainty associated with the different ways of normalizing and aggregating the F-II-I variables was 0.11. The pattern of inequality represented by F-II-I is consistent with similar studies and with the World Bank's Poverty Line. This research contributes to the practice as it combines methods and techniques that make it possible to measure phenomena without strict definition and to consider conflicting opinions expressed in different ways. As a theoretical contribution, this research demonstrates a certain degree of a satisfactory definition of intra-urban inequality. Besides, even if this definition's limits remain unclear, there is a reasonable consensus degree on specific aspects of inequality. [ABSTRACT FROM AUTHOR]

Due to the increase of network equipments and the uncertainty of the transmission environment, the message delay is also uncertain, and the asynchronous consensus protocol possesses more advantages. Miller et al proposed the first asynchronous consensus protocol HoneyBadgerBFT in 2016, but its transmission efficiency can be optimized furthermore while achieving high throughput. The broadcast protocol in HoneyBadgerBFT was improved by reducing the message complexity in the broadcast process, and adding optional message request process to achieve rapid response and efficient transmission.

Pneumocystis jirovecii is associated with non-noxious colonization or severe pneumonia in immunocompromised hosts. Epidemiological investigations have been hampered by the lack of a standardized typing scheme. Thus, only partial molecular data on Spanish P. jirovecii cases are available. Recently, a new ISHAM consensus multilocus sequence typing scheme (MLST) targeting β-TUB, mt26S, CYB , and SOD with a publicly accessible database has been launched to overcome this problem.  The molecular epidemiology of P. jirovecii from immunocompromised patients either colonized (n = 50) or having pneumonia (n = 36) seen between 2014 and 2018 at a single center in Barcelona, Spain, was studied. The new ISHAM consensus MSLT scheme was used to investigate the local epidemiology and identify possible unnoticed outbreaks. Mutations in the DHPS gene, not included in the scheme but giving information about potential sulfa treatment failure, were also studied. The study assigned 32 sequence types (ST) to 72.2% pneumonia and 56% colonization cases. The most frequent STs were ST21 (18.5%), ST22 (14.8%), and ST37(14.8%). For non-unique STs, ST3, ST30 and ST31 were found only in pneumonia cases, whereas ST27 was associated exclusively to colonizations. Despite 38 patients sharing similar STs, only two were involved in a potential cross transmission event. No DHPS mutations were identified. The new consensus typing scheme was useful to ascertain the molecular epidemiology of P. jirovecii in our center revealing a high genetic diversity and the potential association of specific STs to colonization and pneumonia cases. Lay Summary A newly described MLST scheme aims at providing a standardized tool to study and compare Pneumocystis jirovecii epidemiology. A high diversity among P. jirovecii isolates from patients in Barcelona, Spain, and a potential association between specific STs and infection/colonization were identified. [ABSTRACT FROM AUTHOR]

This study examines a general scheme of multicriteria decision-making under uncertainty based on quantitative and qualitative information. In its original form, the general scheme uses qualitative information at the final decision stage, only if the quantitative information is unable to generate unique solutions. Considering that many problems require objectives based on qualitative information at all decision stages, the results of Ramalho et al. (2019) can provide such solutions. However, the processing of qualitative information in Ramalho et al. (2019) is based on applying a very simple approach to aggregating individual preferences without analyzing any type of consensus information. Therefore, the present study sets out to show that representative combinations of initial data, states of nature or scenarios can be constructed by using qualitative information directly, based on aggregating individual preferences after achieving the necessary consensus. In particular, a new scheme for consensus construction is proposed. Using this scheme enables negative points inherent in traditional approaches to be avoided and uncertainty levels to be reduced when estimating coefficients of objective functions based on qualitative information. An illustrative example is presented to demonstrate the results that the new proposal can achieve. [ABSTRACT FROM AUTHOR]

The problem of distributed state estimation for time‐varying uncertain systems over a sensor network within the robust Kalman filtering framework is studied. It is assumed that the parameters of the underlying model are subjected to stochastic uncertainties. At the first step, the authors present a particular form of the Kalman filter named information form of a robust Kalman filter. Then, using a consensus scheme that guarantees an agreement in estimation among nodes, they propose a new consensus‐based robust filtering approach. The consensus methodology is a hybrid method that is a combination of consensus on information (CI) and consensus on measurement (CM). To this end, before proposing the hybrid consensus filtering algorithm, distributed robust filtering based on CI and CM have been presented. Next, they show that the estimation error in the proposed consensus algorithm is exponentially mean square bounded using a Lyapunov function. Finally, they provide two illustrative examples to show the robust performance and effectiveness of the proposed consensus filtering algorithms. [ABSTRACT FROM AUTHOR]

Pneumocystis jirovecii is associated with non-noxious colonization or severe pneumonia in immunocompromised hosts. Epidemiological investigations have been hampered by the lack of a standardized typing scheme. Thus, only partial molecular data on Spanish P. jirovecii cases are available. Recently, a new ISHAM consensus multilocus sequence typing scheme (MLST) targeting β-TUB, mt26S, CYB, and SOD with a publicly accessible database has been launched to overcome this problem. The molecular epidemiology of P. jirovecii from immunocompromised patients either colonized (n = 50) or having pneumonia (n = 36) seen between 2014 and 2018 at a single center in Barcelona, Spain, was studied. The new ISHAM consensus MSLT scheme was used to investigate the local epidemiology and identify possible unnoticed outbreaks. Mutations in the DHPS gene, not included in the scheme but giving information about potential sulfa treatment failure, were also studied. The study assigned 32 sequence types (ST) to 72.2% pneumonia and 56% colonization cases. The most frequent STs were ST21 (18.5%), ST22 (14.8%), and ST37(14.8%). For non-unique STs, ST3, ST30 and ST31 were found only in pneumonia cases, whereas ST27 was associated exclusively to colonizations. Despite 38 patients sharing similar STs, only two were involved in a potential cross transmission event. No DHPS mutations were identified. The new consensus typing scheme was useful to ascertain the molecular epidemiology of P. jirovecii in our center revealing a high genetic diversity and the potential association of specific STs to colonization and pneumonia cases., Lay Summary: A newly described MLST scheme aims at providing a standardized tool to study and compare Pneumocystis jirovecii epidemiology. A high diversity among P. jirovecii isolates from patients in Barcelona, Spain, and a potential association between specific STs and infection/colonization were identified., (© The Author(s) 2021. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)