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Compatibility studies are essential for the integration and simultaneous use of chemical and biological pest control methods since they are necessary for an Integrated Pest Management (IPM) program. In this work, the aim was to evaluate the compatibility of insecticides used in soybean and cotton crops for pest control with Bacillus thuringiensis (Bt). The in vitro inoculation technique was used with B. thuringiensis var. kurstaki and B. thuringiensis var. aizawai, in culture medium containing the following insecticides: beta-cyfluthrin (Bulldock®), methomyl (Bazuka®), thiamethoxam + lambda-cialotrina (Engeo Pleno®), zeta-cypermethrin (Fury 200®), acetamiprid (Saurus®), bifenthrin + carbosulfano (Talisman®) and bifenthrin (Talstar®), in Petri dishes. The Petri dishes were taken to the B.O.D. (Biological Oxygen Demand), at a temperature of 30 ± 1 ºC, 70 ± 10% RH (relative humidity) and a photophase of 12 h, for 24 hours. Colony growth was measured, and Colony Forming Units (CFU) counted in the total area of the Petri dish. The product that allowed growth to be significantly equal to or higher than the control was established as compatible, and the one that did not allow growth or was significantly less than the control was incompatible. It was found that all insecticides were classified as incompatible with the bioinsecticide.

This study aimed to evaluate the efficiency of different strains of the entomopathogenic fungus Metarhizium rileyi in the control of Helicoverpa armigera caterpillars in laboratory conditions. Caterpillars between the 2nd and 3rd instar were used, ranging in size from 0.7 to 1.2 cm length. The experimental design used was completely randomized, composed of five treatments and five replications, each one consisting of 50 insects. The treatments T1 - Control (sterile distilled water), T2 - M. rileyi UFMS 02 strain, T3 - M. rileyi UFMS 03 strain, T4 - M. rileyi UFMS 06 strain, and T5 - M. rileyi UFMS 07 strain were evaluated. All treatments were applied (2 mL/insect) in suspensions of the order of 1.0 × 109 conidia mL-1, and Tween 80® was added in all treatments. Evaluations were performed daily to verify mortality and sublethal effects. For emerging adults, Filial Generation (FG), the biological cycle was evaluated. The data referring to larval mortality for the Parental Generation (PG) and GF and pupal for GF were submitted to analysis of variance, and the Scott-Knott test grouped the averages at 5% probability. The strains tested did not provide pathogenicity in the larval phase of H. armigera for PG and FG. However, there was a reduction in oviposition in all treatments regarding the control. There was an effect on the reproductive phase of GF caterpillars exposed to M. rileyi.

Electrical utilities and system operators (SOs) are constantly looking for solutions to problems in the management and control of the power network. For this purpose, SOs are exploring new research fields, which might bring contributions to the power system environment. A clear example is the field of computer science, within which artificial intelligence (AI) has been developed and is being applied to many fields. In power systems, AI could support the fault prediction of cable joints. Despite the availability of many legacy methods described in the literature, fault prediction is still critical, and it needs new solutions. For this purpose, in this paper, the authors made a further step in the evaluation of machine learning methods (ML) for cable joint health assessment. Six ML algorithms have been compared and assessed on a consolidated test scenario. It simulates a distributed measurement system which collects measurements from medium-voltage (MV) cable joints. Typical metrics have been applied to compare the performance of the algorithms. The analysis is then completed considering the actual in-field conditions and the SOs’ requirements. The results demonstrate: (i) the pros and cons of each algorithm; (ii) the best-performing algorithm; (iii) the possible benefits from the implementation of ML algorithms.

O presente trabalho visa analisar o conto “O cobrador” de Rubem Fonseca, abordando seu personagem central em uma crítica às classes brasileiras favorecidas. Este artigo analisa a violência e o sadismo contidos nesta narrativa, por meio do estudo do protagonista, o qual faz parte de um grupo de excluídos socialmente e que se revolta com sua situação, buscando resolvê-la pelos caminhos da violência. É possível compreender a formação desse personagem e, dessa forma, analisar a desigualdade social, o sadismo e a violência, refletidos em um sujeito que atinge o ponto máximo da brutalidade no desejo de mudar a realidade – ações entendidas como uma transgressão. Pretendemos com tal análise demonstrar o quanto a literatura representa a realidade, a sociedade, a cultura e os sentimentos mais obscuros do ser humano, sobretudo pela estética pós-modernista e no ambiente metropolitano consumista; inigualavelmente operacionalizados por Fonseca.

This study aimed to evaluate the conidial production of Metarhizium rileyi in rice with different water volumes. The bioassay was composed by completely randomized design (CRD), with four treatments (20, 30, 40 and 50 mL of distilled water), being added 100 g of rice thin and long, making a total of 10 plastic bags per treatment, which were autoclaved for 15 minutes at 1.0 atm pressure, to 120 ºC. After the cooling of the rice, were added in each plastic bag, 2.0 mL of suspension containing 1 × 108 conidia mL-1. Then the bags were incubated for ten days in a germination chamber (BOD type) at 25 °C (±1 °C), 80% (±10%) relative humidity and 12h photoperiod to promote conidial germination and growth of the fungus, being performed a mild agitation every two days. The use of higher water volume resulted in greater conidial production and greater number of viable conidia. However, the highest rate of conidia germination was obtained with the use of 30 mL of water, is this the volume of water that corresponds to the best results.

International technical committees put considerable efforts into the writing process of standards. They always try to find a tradeoff between the rigorous scientific requirements and the practical needs of manufacturers and final users. In addition, researchers keep investigating to improve the existing standards with new procedures, achievements, and findings. The purpose of this work is to contribute to that direction. It introduces a simplified and low-cost procedure to test low-power voltage transformers (LPVTs). The procedure is designed to assess the immunity of LPVTs when subjected to external electric fields. The need for this procedure comes from the existing immunity test, which is efficient but sometimes difficult to implement. The proposed one, instead, is simpler, cheaper, does not require the application of the rated voltage, and can be replicated at all voltage levels. In the paper, the procedure is described and demonstrated with experimental tests. From the results, it is possible to appreciate the validity of the proposed solution and the different ways it could be developed, implemented, and improved.

The distribution network is experiencing a massive deployment of intelligent electronic devices (IEDs) such as energy meters, protective devices, and phasor measurement units (PMUs). This phenomenon resulted, on the one hand, in (i) the availability of distributed measurement systems capable of monitoring and collecting measurements from the distribution network, and (ii) increasing awareness of the system operator about the status of the network. On the other hand, such a significant number of devices require to be characterized, over the years, and assessed in both sinusoidal and distorted conditions. However, the characterization process may require a huge investment of money and time considering the low availability of reference instruments and accredited laboratories. To this purpose, this paper presents a simple and fast test procedure, performed with cheap and low-voltage instrumentation, to characterize two off-the-shelf low-power medium-voltage sensors in the power quality frequency range. In detail, the paper describes the measurement setup developed for the characterization and the performed tests. In addition, the method was also reproduced with reference equipment for validation purposes. Lastly, for both tests, an uncertainty evaluation was performed to quantify the goodness of the proposed method. From the results, it is possible to appreciate that the designed cheap and simple test can achieve as accurate results as those of a sophisticated and expensive equipment.

Low-Power Instrument Transformers (LPITs) are becoming the first choice for distributed measurement systems for medium voltage networks. However, there are still a lot of challenges related to their operation. Such challenges include their accuracy variation when several influence quantities are acting on them. Among the most significant influence quantities are temperature, electromagnetic field, humidity, etc. Another aspect that increases the importance of studying the LPITs’ accuracy behavior is that, once installed, they cannot be calibrated for several years; hence, one cannot compensate for in-field conditions. Hence, this work aims at introducing a simple type test for a specific LPIT, the Rogowski coil. First, an experimental setup to assess the effect of temperature, humidity, and positioning on the power quality accuracy performance of the Rogowski coil is described. Second, from the results and the experience of the authors it has been possible to design a specific type test. The test has the aim of finding the limits of the accuracy variations of a single Rogowski coil. Afterwards, such limits can be used to compensate for the in-field measurements, obtaining an overall higher accuracy. The results of this work may contribute to the always-evolving standardization work on LPITs.

Power quality evaluation is the process of assessing the actual power network parameters with respect to the ideal conditions. However, several new assets and devices among the grid include mining the voltage and current quality. For example, the power converters needed for renewable energy sources’ connection to the grid, electric vehicles, etc., are some of the main sources of disturbances that inject high-frequency components into the grid. Consequently, instrument transformers (ITs) should be capable of measuring distorted currents and voltages with the same level of accuracy guaranteed for the ideal frequency (50–60 Hz). This is not a simple task if one considers that several other influence quantities endlessly act on the ITs. To this purpose, considering the lack of a standard, this work presents a measurement setup and specific tests for testing a commonly used type of low-power current transformer, the Rogowski coil (RC). In particular, the accuracy performance (ratio error and phase displacement) of the RCs was evaluated when measuring distorted signals while other influence quantities affected the RCs. Such quantities included positioning, burden, and magnetic field. The results indicate which quantities (or combination of them) have the greatest effect on the RC’s accuracy performance.

Objetivou-se avaliar a compatibilidade dos inseticidas químicos (Orthene® 750 BR, Mospilan®, Imidacloprid® NORTOX e Evidence® 700 WG), sobre o desenvolvimento de Metarhizium rileyi. Os experimentos foram realizados “in vitro”, avaliando os efeitos sobre o crescimento vegetativo, produção de conídios (esporulação) e germinação do fungo M. rileyi (isolado UFMS 03) na presença de diferentes inseticidas. Após a obtenção dos dados de diâmetro de colônias, produção de conídios e germinação foram calculados o fator de compatibilidade. Os inseticidas Mospilan®, Imidacloprid® NORTOX e Evidence® 700 WG proporcionaram crescimento vegetativo semelhante a testemunha, considerados compatíveis com M. rileyi enquanto que Orthene® 750 BR foi considerado moderadamente tóxico. Os inseticidas Imidacloprid® NORTOX e Evidence® 700 WG não interferiram na produção de conídios proporcionando valores semelhantes a testemunha. Não houve efeito dos tratamentos sobre a germinação dos conídios de M. rileyi.

Objetivou-se avaliar o efeito do sal de ácido carboxílico no controle de Aphis gossypi.Para instalação dos experimentos, adultos em fase reprodutiva foram coletados em plantas de algodão cultivadas em casa de vegetação e levados ao laboratório, sendo acondicionados em placas de Petri (6 cm de diâmetro) contendo discos foliares de algodão fixadas em uma fina camada solidificada de ágar-água. Os adultos permaneceram nos discos por 24 horas, sendo as ninfas produzidas utilizadas para aplicação dos tratamentos. Foram utilizadas ninfas de primeiro e terceiro ínstares. Os tratamentos foram aplicados com auxílio de torre de Potter sendo compostos por diferentes concentrações do sal de ácido carboxílico BIO ADD (0,25%; 0,5% e 0,75%), além do tratamento testemunha composto por água destilada esterilizada. Após as aplicações, as placas de Petri foram transferidas para câmaras climatizadas sendo mantidas a 25 ± 1ºC, umidade relativa do ar de 70 ± 10% e fotofase de 12 horas, avaliando-se a mortalidade e a eficiência em cada concentração do produto. O primeiro instar de A. gossypii foi o mais suscetível independente da concentração do produto testada e a concentração de 0,75 % de BIO ADD proporcionou as maiores taxas de mortalidade e eficiência, independente do instar de A. gossypii.

We explore CO2 injection into a layered permeable rock consisting of high permeability reservoir layers, separated by low permeability mudstone, and taking the shape of an anticline within a laterally extensive aquifer. We first show how the storage capacity of the formation depends on the capillary entry pressure of the inter-layer mudstone, so that CO2 cannot flow from one layer into the next. We then consider a formation composed of two layers, overlain by a cap rock. For injection into the lowest layer, we show that the injection rate, capillary entry pressure and buoyancy driven flux through the mudstone determine whether the lower or upper layer fills to the spill point first. We also show that at the end of the injection phase, CO2 may continue to flow from the lower to the upper layer. This implies that injection should be stopped once the injected volume matches the static capacity of the formation in order to prevent spilling after injection. We present a series of analogue experiments of a two layered system that illustrate some of the principles described by the model, and assess the implications of the results for field scale systems [ABSTRACT FROM AUTHOR]

In recent years, the introduction of real-time simulators (RTS) has changed the way of researching the power network. In particular, researchers and system operators (SOs) are now capable of simulating the complete network and of making it interact with the real world thanks to the hardware-in-the-loop (HIL) and digital twin (DT) concepts. Such tools create infinite scenarios in which the network can be tested and virtually monitored to, for example, predict and avoid faults or energy shortages. Furthermore, the real-time monitoring of the network allows estimating the status of the electrical assets and consequently undertake their predictive maintenance. The success of the HIL and DT application relies on the fact that the simulated network elements (cables, generation, accessories, converters, etc.) are correctly modeled and characterized. This is particularly true if the RTS acquisition capabilities are used to enable the HIL and the DT. To this purpose, this work aims at emphasizing the role of a preliminary characterization of the virtual elements inside the RTS system, experimentally verifying how the overall performance is significantly affected by them. To this purpose, a virtual phasor measurement unit (PMU) is tested and characterized to understand its uncertainty contribution. To achieve that, firstly, the characterization of a virtual PMU calibrator is described. Afterward, the virtual PMU calibration is performed, and the results clearly highlight its key role in the overall uncertainty. It is then possible to conclude that the characterization of the virtual elements, or models, inside RTS systems (omitted most of the time) is fundamental to avoid wrong results. The same concepts can be extended to all those fields that exploit HIL and DT capabilities.

Distribution networks are currently subject to a huge revolution in terms of assets being installed. In particular, the massive spread of renewable energy sources has drastically changed the way of approaching the grid. For example, renewables affected (i) the production of the legacy power plants, (ii) the quality of the supplied energy, decreasing it, (iii) the fault detection and location, etc. To mitigate the significant drawbacks of the renewables’ presence, several intelligent electronic devices have been (and are being) developed and installed among the grid. The aim is to increase grid monitoring and knowledge of its status. However, considering the significant number of nodes of the distribution network, compared to the transmission one, the process of installing new equipment is not effortless and is also quite expensive. This work aims at emphasizing a new concept of distributed monitoring systems, based on the phasor measurement unit’s current measurements, and a controlling algorithm to exploit it. The idea underneath the work is to avoid the out-of-service time needed and the costs associated with the installation of voltage sensors. Therefore, this paper describes an algorithm that exploits measurements from existing equipment and current measurements from PMUs to obtain information on the load and the node voltages. The algorithm is then tested on simulated power networks of increasing complexity and verified with an uncertainty evaluation. The results obtained from the simulation confirm the applicability and effectiveness of the algorithm and the benefits of a current-based monitoring system.