Decision-making analysis in cooperative environments for decentralized cognitive radio networks.

Currently, there are saturated frequency bands that affect the quality of service for new users. Cognitive radio provides an alternative solution to this problem through dynamic spectrum access. However, the solutions proposed in the current literature are focused on a centralized network and do not allow demonstrating the behavior in a multi-user environment, much less the effect that cooperation between secondary users can have. This article establishes a decision-making model for the best spectral opportunity selection with a cooperative approach in decentralized cognitive radio networks and contrasts its results with three multi-criteria decision-making algorithms: SAW, TOPSIS, and VIKOR. So, this research suggests a cooperative decision-making model based on four main modules. (1) a collaborative module for the exchange of information between SU; (2) a module for PU characterization; (3) a module of the probability of SU arrival; and (4) the SO feedback selection module. The results are obtained through simulations fed with experimental spectral occupancy data captured in a measurement campaign. Handoff and throughput were used as evaluation metrics, along with five levels of collaboration: 10%, 20%, 50%, 80%, and 100%, and eight different scenarios based on the type of network: GSM and Wi-Fi, the application type: real-time and best-effort, and the level of traffic: high and low. The contribution of this study lies in the fact that no current work includes the following relevant aspects for an adequate validation and evaluation of this proposal: First, the consideration of a decentralized cognitive radio network; second, the decision-making with cooperative strategies; third, different techniques for SO selection; fourth, the validation and evaluation with experimental spectral occupancy data captured in measurement campaigns; finally, the performance analysis in diverse networks, traffic levels, and types of applications.

Secure Aggregation Protocol Based on DC-Nets and Secret Sharing for Decentralized Federated Learning.

In the era of big data, millions and millions of data are generated every second by different types of devices. Training machine-learning models with these data has become increasingly common. However, the data used for training are often sensitive and may contain information such as medical, banking, or consumer records, for example. These data can cause problems in people's lives if they are leaked and also incur sanctions for companies that leak personal information for any reason. In this context, Federated Learning emerges as a solution to the privacy of personal data. However, even when only the gradients of the local models are shared with the central server, some attacks can reconstruct user data, allowing a malicious server to violate the FL principle, which is to ensure the privacy of local data. We propose a secure aggregation protocol for Decentralized Federated Learning, which does not require a central server to orchestrate the aggregation process. To achieve this, we combined a Multi-Secret-Sharing scheme with a Dining Cryptographers Network. We validate the proposed protocol in simulations using the MNIST handwritten digits dataset. This protocol achieves results comparable to Federated Learning with the FedAvg protocol while adding a layer of privacy to the models. Furthermore, it obtains a timing performance that does not significantly affect the total training time, unlike protocols that use Homomorphic Encryption.

Bio-Inspired Autonomous Navigation and Formation Controller for Differential Mobile Robots.

This article proposes a decentralized controller for differential mobile robots, providing autonomous navigation and obstacle avoidance by enforcing a formation toward trajectory tracking. The control system relies on dynamic modeling, which integrates evasion forces from obstacles, formation forces, and path-following forces. The resulting control loop can be seen as a dynamic extension of the kinematic model for the differential mobile robot, producing linear and angular velocities fed to the mobile robot's kinematic model and thus passed to the low-level wheel controller. Using the Lyapunov method, the closed-loop stability is proven for the non-collision case. Experimental and simulated results that support the stability analysis and the performance of the proposed controller are shown.

Characterizing Organizational Lifecycle through Strategic and Structural Flexibility: Insights from MSMEs in Mexico.

Today's lifespan of companies tends to be low in the so-called micro-, small-, and medium-sized enterprises (MSMEs). Organizational life cycle (OLC) theory indicates that organizational aging is related, but not determined, by the firm chronological age or its size. Therefore, a firm's aging should be analyzed by other factors such as flexibility. The literature considers flexibility as an essential capability, a source of competitive advantage, and an enabler of long-term growth for MSMEs. However, little attention in emerging economies has been paid to examine the nuances of this concept in relation to the OLC in this type of companies. Additionally, studies tend to analyze flexibility as a general term, ignoring that it is a polymorphic concept. That is why there is a need to research the different categories of flexibility. Drawing on a quantitative approach conducting a factor analysis, a two-step cluster, and decision tree analysis to interrogate data from 257 MSMEs in Mexico, this study provides evidence of different dimensions of strategic and structural flexibility that help to characterize and predict the growth, maturity, and declining stages of MSMEs. Our results show that mature firms present more strategic and structural flexible characteristics than those involved in growth or decline stages. The flexible factors that help classify and predict an MSME in the maturity stage include open communication, decentralized decision making, and formalization. We provide a model with these results to illuminate unaddressed issues regarding the broad term of flexibility and its relationship to OLC.

Household slow sand filters in continuous and intermittent flows and their efficiency in microorganism's removal from river water.

This study aimed to evaluate the efficiency of four household slow sand filter (HSSF) models for the removal of microorganisms from river water throughout the development of their biological layers (schmutzdecke). Two models were designed to be operated continuously (HSSF-CC and HSSF-CT) and two intermittently (HSSF-ID and HSSF-IF). Filters were fed daily with 48 L pre-treated river water (24 h sedimentation followed by filtration through a non-woven synthetic blanket). Water samples were quantified by coliform group bacteria and analysed by bright field microscopy to visualize the microorganisms. Total coliform reduction was between 1.42 ± 0.59 log and 2.96 ± 0.58 log, with continuous models showing a better performance (p-values < 0.004). Escherichia coli reduction varied from 1.49 ± 0.58 log to 2.09 ± 0.66 log and HSSF-IF, HSSF-CC and HSSF-CT presented a similar performance (p-values > 0.06), slightly better than the one presented by HSSF-ID (p-value=0.04). Microorganisms, such as algae, protozoa and helminths were detected by microscopy in raw water and pre-treated water. Algae were the most significant group in these samples, although they were not visualized by bright field microscopy in the filtered water. Results showed the potential of HSSF in microbiological risk reduction from river water, which increases the range of point-of-use water treatments in rural communities. However, additional studies of the HSSF biological layer must be performed.

Filter media depth and its effect on the efficiency of Household Slow Sand Filter in continuous flow.

This study evaluated the impact of a 50% reduction of filter media depth in Household Slow Sand Filters (HSSFs) on continuous flow to remove physicochemical and microbiological parameters from river water. Furthermore, simple pre-treatment and disinfection processes were evaluated as additional treatments. Two filter models with different filtration layer depths were evaluated: a traditional one with 50 cm media depth (T-HSSF) and a compact one (C-HSSF) with 25 cm. HSSFs were fed with pre-treated river water (24-h water sedimentation followed by synthetic fabric filtration) for 436 days at a constant filtration rate of 0.90 m3 m-2 day-1 with a daily production of 48 L day-1. Sodium hypochlorite (2.0 mg L-1 of NaOCl 2.5% for 30 min) was used to disinfect the filtered water. Water samples were analysed weekly for parameters such as turbidity, organic matter, colour and E. coli, among others. Removal of protozoan cysts and oocysts by the HSSFs were also evaluated. After pretreatment, turbidity from the HSSF river water was reduced to 13.2 ± 14.6 NTU, allowing the filters to operate. Statistical analysis indicated no significant difference (p > 0.05) between T-HSSF and C-HSSF efficiencies in all evaluated parameters throughout operation time. Hence, media depth reduction did not hinder continuous HSSF performance for almost all the evaluated parameters. However, it may have affected Giardia cysts retaining, which passed through the thinner media on one evaluation day. Disinfection was effective in reducing remaining bacteria from filtered water; however, it was ineffective to inactivate protozoa. The reduction in the filtration layer did not affect the overall filtered water quality or quantity showing that a compact HSSF model may be a viable option for decentralized water treatment.

Key criteria for considering decentralization in municipal wastewater management.

Wastewater pollution problems are associated with population growth and the concentration of population in large urban centers. According to United Nations projections for 2050, the world population will reach 9 billion people, increasing the pressures on water resources due to their demand and pollution. Based on UNICEF and World Health Organization estimates, 2.4 billion people worldwide currently lack access to improved sanitation facilities, with 946 million practicing open defecation. Decentralized wastewater treatment systems are a viable and necessary alternative for wastewater management, thus, minimizing environmental impacts, facilitating resource recovery, and providing rural and peri-urban inhabitants with access to basic sanitation. This literature review article uses the multicriteria analysis tool to present the key economic, institutional, social, environmental, and technological aspects, criteria, and indicators that must be considered for successful decentralized system implementation planning to strengthen basic sanitation service coverage in the rural and peri-urban areas where it does not exist.

A Robotic Cognitive Architecture for Slope and Dam Inspections.

Big construction enterprises, such as electrical power generation dams and mining slopes, demand continuous visual inspections. The sizes of these structures and the necessary level of detail in each mission requires a conflicting set of multi-objective goals, such as performance, quality, and safety. It is challenging for human operators, or simple autonomous path-following drones, to process all this information, and thus, it is common that a mission must be repeated several times until it succeeds. This paper deals with this problem by developing a new cognitive architecture based on a collaborative environment between the unmanned aerial vehicles (UAVs) and other agents focusing on optimizing the data gathering, information processing, and decision-making. The proposed architecture breaks the problem into independent units ranging from sensors and actuators up to high-level intelligence processes. It organizes the structures into data and information; each agent may request an individual behavior from the system. To deal with conflicting behaviors, a supervisory agent analyzes all requests and defines the final planning. This architecture enables real-time decision-making with intelligent social behavior among the agents. Thus, it is possible to process and make decisions about the best way to accomplish the mission. To present the methodology, slope inspection scenarios are shown.

Influence of rain events on the efficiency of a compact wastewater treatment plant: a case study on a university campus aiming water reuse for agriculture.

In this study, the efficiency of contaminant removal from a compact wastewater treatment plant (CWTP) in a university campus under different rain conditions was evaluated. Wastewater samples were collected weekly for 1 year and the physicochemical parameters were monitored. Removal efficiency higher than 77%, reaching values above 95% for samples with lower wastewater flow rates, was found for biological oxygen demand (BOD) and total and fecal coliforms. The pH values remained in the range of 6.0-8.0. However, pH values below 6.8 impaired the nitrification rate and, therefore, the removal of total Kjeldahl nitrogen (TKN) and ammonia was lower than the expected, with concentration values above those set by the Brazilian regulation for wastewater discharge. The results show that the flow rate of wastewater at the entrance of the CWTP is directly related to the rain events, thus affecting its efficiency, mainly in the removal of total solids, turbidity, and organic matter. The assessment of the treated wastewater reuse on site for agricultural purposes showed to be a prominent and more sustainable alternative regarding the discharge of wastewater into water bodies.

A Decentralized Low-Chattering Sliding Mode Formation Flight Controller for a Swarm of UAVs.

In this paper, a nonlinear robust formation flight controller for a swarm of unmanned aerial vehicles (UAVs) is presented. It is based on the virtual leader approach and is capable of achieving and maintaining a formation with time-varying shape. By using a decentralized architecture, the local controller in each UAV uses information only from the UAV itself, its neighbors, and from the virtual leader. Also, a synchronization control objective provides a mechanism to weight between the fleet achieving the desired formation shape, that is, achieving the desired relative position between the UAVs, and each UAV achieving its desired absolute position. The use of a combination of a sliding mode controller and a low pass filter reduces the usual chattering effect, providing a smooth control signal while maintaining robustness. Simulation results show the effectiveness of the proposed decentralized controller.

Blockchain Mechanism and Symmetric Encryption in A Wireless Sensor Network.

The Internet of Things (IoT) paradigm allows the connection and exchange of information between millions of smart devices. This paradigm grows and develops exponentially as do the risks and attacks on IoT infrastructures. Security, privacy, reliability, and autonomy are the most important requirements in IoT Systems. If these issues are not guaranteed, the IoT system could be susceptible to malicious users and malicious use. In centralized IoT systems, attacks and risks are greater, especially when data is transmitted between devices and shared with other organizations. To avoid these types of situations, this work presents a decentralized system that guarantees the autonomy and security of an IoT system. The proposed methodology helps to protect data integrity and availability based on the security advantages provided by blockchain and the use of cryptographic tools. The accuracy of the proposed methodology was measured on a temperature and humidity sensing IoT-based Wireless Sensor Network (WSN). The obtained results prove that the proposal fulfils the main requirements of an IoT system. It is autonomous, secure to share and send information between devices and users, has privacy, it is reliable, and the information is available in the infrastructure. Furthermore, this research demonstrates that the proposal is less susceptible to the most frequent attacks against IoT systems, such as linking attack, man in the middle, and Distributed Denial of Service (DDoS) attack.

Breast cancer treatment: A phased approach to implementation.

Optimal treatment outcomes for breast cancer are dependent on a timely diagnosis followed by an organized, multidisciplinary approach to care. However, in many low- and middle-income countries, effective care management pathways can be difficult to follow because of financial constraints, a lack of resources, an insufficiently trained workforce, and/or poor infrastructure. On the basis of prior work by the Breast Health Global Initiative, this article proposes a phased implementation strategy for developing sustainable approaches to enhancing patient care in limited-resource settings by creating roadmaps that are individualized and adapted to the baseline environment. This strategy proposes that, after a situational analysis, implementation phases begin with bolstering palliative care capacity, especially in settings where a late-stage diagnosis is common. This is followed by strengthening the patient pathway, with consideration given to a dynamic balance between centralization of services into centers of excellence to achieve better quality and decentralization of services to increase patient access. The use of resource checklists ensures that comprehensive therapy or palliative care can be delivered safely and effectively. Episodic or continuous monitoring with established process and quality metrics facilitates ongoing assessment, which should drive continual process improvements. A series of case studies provides a snapshot of country experiences with enhancing patient care, including the implementation of national cancer control plans in Kenya, palliative care in Romania, the introduction of a 1-stop clinic for diagnosis in Brazil, the surgical management of breast cancer in India, and the establishment of a women's cancer center in Ghana.

Recycling and Updating an Educational Robot Manipulator with Open-Hardware-Architecture.

This article presents a methodology to recycle and upgrade a 4-DOF educational robot manipulator with a gripper. The robot is upgraded by providing it an artificial vision that allows obtaining the position and shape of objects collected by it. A low-cost and open-source hardware solution is also proposed to achieve motion control of the robot through a decentralized control scheme. The robot joints are actuated through five direct current motors coupled to optical encoders. Each encoder signal is fed to a proportional integral derivative controller with anti-windup that employs the motor velocity provided by a state observer. The motion controller works with only two open-architecture Arduino Mega boards, which carry out data acquisition of the optical encoder signals. MATLAB-Simulink is used to implement the controller as well as a friendly graphical interface, which allows the user to interact with the manipulator. The communication between the Arduino boards and MATLAB-Simulink is performed in real-time utilizing the Arduino IO Toolbox. Through the proposed controller, the robot follows a trajectory to collect a desired object, avoiding its collision with other objects. This fact is verified through a set of experiments presented in the paper.

Pretreatment using Opuntia cochenillifera followed by household slow sand filters: technological alternatives for supplying isolated communities.

Household slow sand filter (HSSF) performance in continuous and intermittent flows was evaluated when influent water was treated with a natural coagulant extracted from Opuntia cochenillifera. The water under study, used as influent, had a turbidity of 111 ± 17.3 NTU. When clarifying the water with O. cochenillifera, the best condition obtained was 30  mg L-1 in natural pH (without correction), generating clarified water with turbidity satisfactory to filters operation (7.83 ± 2.32 NTU). The results indicated a better performance of continuous flow HSSF in turbidity removal (79.2% ± 8.39%) and higher efficiency of intermittent flow HSSF in the removal of E. coli (2.86 log ± 0.79 log for 12  h pause period and 2.41 log ± 0.42 log for 4  h pause period). For the sake of comparison, the evaluated HSSFs had the same production (60 L day-1). The impact on the interruption of the 96-h feed into the HSSFs was analysed and the results indicated a significant change in the quality of the filtered water after resuming the operation. This fragility of technology must be considered when it is implemented as lack of water can be a reality in the target communities. Acute toxicological assays with C. xanthus larvae showed no toxicity for pretreated and filtered water; however, more testing should be performed.

Considerations on design and implementation parameters of domestic wastewater treatment by subsurface flow constructed wetlands / Considerações sobre parâmetros de dimensionamento e implantação de wetland construída de fluxo subsuperficial no tratamento de esgoto doméstico

ABSTRACT Constructed wetlands might be an alternative for communities away from urban centers and not served by a domestic wastewater treatment system. The purpose of this study was to provide instructions for the implementation of subsurface flow constructed wetland systems. To that end, we gathered information regarding the construction aspect, plants, and operational parameters used in systems which already operate in the country and the respective efficiency of these sets after previous treatment. The system in real scale proposed by Oliveira et al. (2005) was prominent among those that presented the highest efficiency. It was preceded by upflow anaerobic reactor built in brick, with macrophyte of the Typha genre, crushed stone at the entry and exit of the system, and sand in its intermediate portion. It required 1.04 m² surface area per inhabitant in humid temperate climate and hot summer, 1.71 m³ d-1 flow, and one-day hydraulic detention. The considerations presented here might help the construction of this kind of system, regarding dimensional and operational criteria.

RESUMO As wetlands construídas podem ser uma alternativa para comunidades afastadas de centros urbanos que não são atendidas por rede de tratamento de esgoto. Visando à orientação para implantação do sistema de wetlands construídas de fluxo subsuperficial, foi levantada uma série de informações a respeito dos aspectos construtivos, das plantas e parâmetros operacionais utilizados em sistemas já em funcionamento no país e a respectiva eficiência do conjunto, após um tratamento precedente. Entre os sistemas que apresentaram melhor eficiência, destacou-se o de Oliveira et al. (2005) em escala real, precedido por reator anaeróbio de fluxo ascendente, construído em alvenaria, com a macrófita do gênero Typha, brita na entrada e saída do sistema e areia na parte intermediária, com uma área superficial de 1,04 m2 por habitante de clima temperado úmido com verão quente, vazão de 1,71 m3 d-1 e tempo de detenção hidráulica de um dia. A elaboração das considerações apresentadas neste trabalho pode auxiliar na construção desse tipo de sistema, construído nos critérios de dimensionamento e operação.

HIV/AIDS health services in Manaus, Brazil: patient perception of quality and its influence on adherence to antiretroviral treatment.

BACKGROUND: Patient satisfaction is an important factor for both assessing the quality of healthcare and predicting positive health outcomes. This study assesses the influence of HIV/AIDS patients' perception of the quality of health services on adherence to antiretroviral treatment using the decentralized care model in Manaus, Brazil. METHODS: We conducted a non-randomized, cross-sectional analysis to explore the relationship between patient satisfaction and adherence to antiretroviral treatment (ART) in Manaus, Amazonas, Brazil. We also compared patient satisfaction levels at the city's main hospital with those at smaller health units established to decentralize HIV/AIDS healthcare. Using survey responses from 812 patients and health data from 713 patients, we conducted descriptive and regression analyses to identify health center characteristics associated with higher patient satisfaction and higher adherence to treatment. RESULTS: We found a clear and positive relationship between patient satisfaction with the quality of health services and adherence to ART. Patients who had better access to their health center and its services -mainly in the form of convenient location, shorter commute times, and shorter wait times- tended to rate the quality of services higher and were also more likely to adhere to ART. We also found higher levels of patient satisfaction and adherence to ART among patients served at decentralized health units than among patients served at the main hospital. CONCLUSIONS: The study's results emphasize the importance of patients' experience at the health center for improved health outcomes. While many of the factors that play a role in whether a patient adheres to ART or not are beyond the control of the health center, our findings highlight that health centers can importantly contribute to increased ART adherence by improving such experience. The study also showcases the potential benefits of decentralizing HIV care to increase patient satisfaction and, with it, adherence to ART.

Household-based biodigesters promote reduction of enteric virus and bacteria in vulnerable and poverty rural area.

The present study evaluated the river water quality improvement by implementation of household-based biodigesters in vulnerability and poverty rural area, in Minas Gerais State-Brazil. For that, 78 household-based biodigesters were installed for domestic wastewater treatment. Wastewater was collected before and after treatment and the physicochemical parameters and pathogens removal (human adenovirus (HAdV), hepatitis A (HAV) virus, Salmonella sp. and Escherichia coli) were evaluated; Additionally, river water was sampled before and after the household-based biodigesters implementation, to verify the contamination reduction and the positive impact of domestic wastewater treatment on waterborne pathogen reduction, considering HAdV, HAV, Salmonella sp. and E. coli quantification. The applicability in real-scale of decentralized treatment systems using household-based biodigesters promoted reduction of 90, 99, 99.99 and 99.999% from HAV, Salmonella sp., E. coli and HAdV from domestic wastewater, respectively; The river water quality improvement before the wastewater treatment application was highlight in the present study, considering that the reduction of waterborne pathogens in this water in 90, 99.99 and 99.999% of E. coli, HAV and HAdV, respectively (Salmonella sp. was not detected in river water). In general, this is an important study for encouraging the decentralized sanitation in vulnerable and poverty area, as well in rural sites, considering the positive impact of this implementation on public health.

Algae turf scrubber and vertical constructed wetlands combined system for decentralized secondary wastewater treatment.

Water shortage is a current problem faced by many regions. The deterioration of water bodies driven by the directly discard of untreated wastewater worsens the water shortage and implies in more costly treatments to meet local standards for water quality. In rural areas, the problem is even worse, once conventional centralized treatment plants do not encompass them. Decentralized treatment systems must present low-cost, local availability, standards-meeting efficiency, and simplified operation. The present study examines the combined use of algae turf scrubber and down-flow vertical constructed wetlands for a University's sanitary wastewater treatment. After a hydraulic detention time of 21 days, the unit was able to reach 49%, 48%, 98%, 82%, 99.2%, 70.1%, 44%, 83%, 72%, 86%, 69%, 95%, and 99.9% for conductivity, total soluble solids, turbidity, apparent color, N-NH3, total nitrogen, P-soluble, total carbon, chemical oxygen demand, inorganic carbon, TOC, Escherichia coli, and total coliforms. In accord to the Brazilian standard ABNT 13969/97, the treated effluent is eligible for reuse in floor and sidewalks washing, garden irrigation, and landscaping purposes.

Projeto de otimização de sistemas anaeróbios para tratamento de esgoto em escala unifamiliar / Design optimization of a simple single family anaerobic sewage treatment system

RESUMO O objetivo do presente trabalho é propor uma nova configuração de reatores Upflow Anaerobic Sludge Blanket (UASB) para utilização no tratamento unifamiliar, sendo menores e mais eficientes do que o tradicional tanque séptico. O sistema experimental foi projetado em escala piloto, constituindo-se de oito reatores UASB de 250 L cada. Seis dessas unidades são modificadas, mas mantêm o conceito e os princípios dos reatores UASB convencionais; no entanto, foram projetados com geometria diferenciada, alternando-se as zonas de sedimentação e digestão. Comparativamente a esses reatores, foram operados um reator UASB-Y e um UASB convencional. Todos os reatores foram capazes de digerir esgoto bruto de forma eficiente em tempos de detenção hidráulica de 12 e 6 horas. Foram obtidas eficiências de remoção do material orgânico de 67 a 74%. A análise de variância (ANOVA) mostrou que não houve diferença significativa entre as eficiências obtidas nos diferentes reatores. Uma elevada concentração de lodo foi retida na zona de digestão, obtendo-se, assim, elevada capacidade de tratamento. Os ensaios de sedimentação mostraram que as constantes de sedimentação obtidas para o lodo do reator são melhores que as obtidas para o lodo expulso juntamente com o efluente. Em contrapartida, as atividades metanogênicas dos lodos do reator e expulso não diferem significativamente.

ABSTRACT The aim of this work is to propose a new configuration UASB (Upflow Anaerobic Sludge Blanket) for use in single-family treatment, which is smaller and more efficient than the traditional septic tank (TS). The experimental system was designed on a pilot scale, consisting of eight reactors UASB 250 L each. Six of these units are modified, but keep the concept and principles of conventional UASB reactors; they were, however, designed with different geometry, alternating zones of sedimentation and digestion. Compared to these reactors, an UASB reactor-Y and a conventional UASB were operated. All reactors were able to digest raw sewage efficiently in hydraulic retention times (HRT) of 24:06 hours. Organic material removal efficiencies of 67-74% were obtained. Analysis of variance (ANOVA) showed no significant difference between the efficiencies obtained in the different reactors. A high sludge concentration was retained in the digestion zone, thus yielding, high capacity treatment. Sedimentation tests have shown that the constants obtained for the sedimentation sludge reactor are better than those obtained for the sludge which is expelled with the effluent. In contrast, sludge methanogenic activity of the reactor and expelled sludge is not significantly different.

Performance of centralized versus decentralized tuberculosis treatment services in Southern Brazil, 2006-2015.

BACKGROUND: Tuberculosis (TB) control programs face the challenges of decreasing incidence, mortality rates, and drug resistance while increasing treatment adherence. The Brazilian TB control program recommended the decentralization of patient care as a strategy for combating the disease. This study evaluated the performance of this policy in an area with high default rates, comparing epidemiological and operational indicators between two similar municipalities. METHODS: This study analyzed epidemiological and operational indicators on new cases of pulmonary tuberculosis reported in the Brazilian Notifiable Diseases Information System between 2006 and 2015. In addition, to characterize differences between the populations of the two studied municipalities, a prospective cohort study was conducted between 2014 and 2015, in which patients with new cases of culture-confirmed pulmonary tuberculosis were interviewed and monitored until the disease outcome. A descriptive analysis, the chi-square test, and a Poisson regression model were employed to compare TB treatment outcomes and health care indicators between the municipalities. RESULTS: Two thousand three hundred nine cases were evaluated, of which 207 patients were interviewed. Over the 2006-2015 period, TB incidence per 100,000 population in the municipality with decentralized care was significantly higher (39%, 95% CI 27-49%) in comparison to that of the municipality with centralized care. TB treatment default rate (45%, 95% CI 12-90%) was also higher in the municipality with decentralized care. During the two-year follow-up, significant differences were found between patients in centralized care and those in decentralized care regarding treatment success (84.5 vs. 66.1%), treatment default (10.7 vs. 25.8%), illicit drug use (27.7 vs. 45.9%), and homelessness (3.6 vs. 12.9%). The operational indicators revealed that the proportion of control smear tests, medical imaging, and HIV tests were all significantly higher in the centralized care. However, a significantly higher proportion of patients started treatment in the early stages of the disease in the municipality with decentralized care. CONCLUSIONS: These data showed a low success rate in TB treatment in both municipalities. Decentralization of TB care, alone, did not improve the main epidemiological and operational indicators related to disease control when compared to centralized care. Full implementation of strategies already recommended is needed to improve TB treatment success rates.