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Remotely piloted aerial application systems (RPAAS) are exponentially increasing globally for pesticide applications. Evaluations of spray coverage, deposits, and droplet size, when implementing various application parameters, are needed to optimize these applications. A RPAAS at 46.8 L ha-1 provided similar or greater coverage and deposits to ground equipment at 93.5 L ha-1 across nozzle types evaluated excluding the XR. The RPAAS at 18.7 L ha-1 had reduced coverage (

Building efficient and effective road traffic monitoring systems has become a major challenge in different countries, mainly due to the rapid growth of the metropolis road network and the booming of vehicles. Existing traffic monitoring methods are accurate but typically come with inherent limitations, prompting the exploration of alternative techniques. Integrated sensing and communication (ISAC) offers an effective approach to traffic monitoring by leveraging the synergy between sensing and communication to enhance system efficiency and reduce costs. In this paper, we present a particular ISAC use case tailored for radio-based traffic monitoring. Both traffic density and speed estimations take advantage of communication functionality, involving the reuse of communication waveforms for the sensing purpose. In particular, proactive millimeter-wave (mmWave) beam allocation aided by traffic density estimation is studied to enhance communication coverage of vehicular users in the area of interest for bandwidth-intensive applications. Specifically, we exploit orthogonal frequency division multiplexing (OFDM) communication signals of opportunity reflected from targets (vehicles) to efficiently estimate the road traffic density and speed in a road section. A hybrid scheme combining model-based and data-driven methods is considered to build efficient estimators that require reduced-size training data and are less computationally complex. Simulation and comparison results demonstrate that the proposed traffic estimation techniques can accurately handle a wide range of numbers of vehicles, even with a small-sized dataset. Furthermore, the proactive beam allocation analysis shows that the quality of service (QoS, in terms of outage probability) of the communication system is effectively improved.

Millimeter Wave (mmWave) communication technology is anticipated to play a vital role in meeting the growing demand for the scarce bandwidth in wireless communications. However, mmWave networks are highly susceptible to blockage. Thus, some mitigation techniques, such as multi-connectivity, need to be considered. Densely deploying mmWave base stations (mBSs) to form an ultra-dense network (UDN) also helps. With a mix of different technologies, optimally allocating resources becomes challenging. In this paper, we study mmWave user multi-association in a two-tier heterogeneous ultra-dense network (HetUDN) with a relatively large number of user equipments (UEs). We propose a framework of multi-agent reinforcement learning (MARL) to tackle the complicated optimization problem, leveraging its adaptivity to the communication environment. The proposed scheme considers mmWave beam-division based multi-connectivity and takes advantage of a macro base station (MBS) for indirect cooperation among agents (UEs). In particular, we borrow a credit-assignment technique called difference reward (DR) to deal with a relatively large MARL system with a large action space, which, to the best of our knowledge, is the first time to apply MARL with DR in user association. Furthermore, the proposed schemes are scalable mainly due to fixed observation dimensions and individual actions taken by UEs independently, ensuring that the operation is independent of the numbers of mBSs and UEs. Numerical results suggest that the two MARL schemes with measured DR could achieve a good balance between energy efficiency and QoS outage, and the one using extended DR (EDR) offers additional performance improvement.

The objective of this study was to investigate the microalgal dewatering efficiency of a belt filter system for feed concentrations below 10 g dry wt./L. A prototype belt filtration system designed for 50 g dry wt./L microalgal feed concentration was used for this investigation. The highest concentration of microalgal suspension available for testing on the prototype belt filtration system was 6 g dry wt./L obtained from biomass settling tanks at the Lawrence, Kansas domestic wastewater treatment plant. For preparation of feed suspension with concentrations below 10 g dry wt./L, microalgal cultivation was followed by flocculation. A mixed laboratory culture of freshwater species dominated by three eukaryotic green microalgae (Chlorella vulgaris, Scenedesmus sp., and Kirchneriella sp.) was cultivated in wastewater effluent. This was followed by flocculation which resulted in a microalgal feed suspension concentration of 4 g dry wt./L. Belt dewatering tests were conducted on microalgal suspensions with feed concentrations of 4 g dry wt./L and 6 g dry wt./L. The maximum microalgal recovery with the belt dewatering system was 46% from the 4 g dry wt./L, and 84% from the 6 g dry wt./L suspensions respectively. The results of this study indicate that microalgal suspension concentrations as low as 6 g dry wt./L can be recovered with a belt filter system improving the overall dewatering efficiency of the system.

What are some major café cultures, and why do they vary? We outline three levels of ideas as an interpretative framework for café cultures. At level one are ideal types like the convivial or the solitary worker in cafes. At level two are propositions about scenes including cafes: 15 scenes dimensions variously favor or shift the types of café values and activities. Third are propositions about the broader social context. We point to factors discouraging cafés in general, like Puritanism, a strong work ethic, and crime; other propositions identify Bohemianism and strong families as shifting café activities and cultures.

OBJECTIVES: In many European countries, external economic incentives are discussed as a policy instrument to promote occupational safety and health (OSH) in enterprises. This narrative case study review aims to support policy-makers in organizations providing such incentives by supplying information about different incentive schemes and their main characteristics such as effectiveness, efficiency, and feasibility. METHODS: The focal point and topic centre network of the European Agency for Safety and Health at Work were used to collect case studies about incentive schemes aimed at supporting the prevention of occupational accidents and diseases in enterprises. Such incentives are rarely described in the scientific literature. To be considered for this review, studies had to focus on external financial benefits that could be provided as part of an insurance-related incentive or a governmental subsidy scheme. RESULTS: In total, 14 cases were included in the review: 6 insurance premium- and 8 subsidy-based schemes. Of these, 13 contained an evaluation of the incentive scheme, of which 7 use quantitative criteria. Three cases provided sufficient data to conduct a cost–benefit analysis. Most qualitative evaluations related to the successful management of the program and the effectiveness of the promoted measures in the workplace. Regarding the latter, quantitative criteria covered accident rates, sick leave, and general improvement in working conditions. The cost–benefit analyses all resulted in a positive payout ratio, ranging from €1.01–4.81 return for every €1 invested. CONCLUSIONS: Generally, we found economic incentive schemes to be feasible and reasonably effective. However, analysis regarding the efficiency of such schemes is scarce and our evaluation of the cost–benefit analysis had to rely on few cases that, nevertheless, delivered positive results for large samples. Besides this finding, our study also revealed deficits in the quality of evaluations. In order to enable policy-makers to make well-informed decisions about public investments in OSH, better standards for reporting and evaluating incentive schemes are needed.

OBJECTIVES: To evaluate the proportion of tuberculosis (TB) cases initially treated with the recommended four-drug regimen of isoniazid (INH), rifampin (RIF), pyrazinamide (PZA) and ethambutol (EMB) or streptomycin; and to identify factors associated with the choice of initial therapy.

The goal of this study was to establish a plant growth promoting bacterial consortium, using strains previously isolated from a solid waste management unit (SWMU), and determine its effectiveness with respect to enhancing saltgrass colonization of contaminated soil from the SWMU. Bacterial strains were identified exhibit certain growth promoting characteristics and were tolerant to site relevant levels of petroleum hydrocarbons, salinity and pH. Five best performing strains including Pseudomonas sp. strain PFS1 and BSS3B2, Serratia proteamaculans strain S1BD1, Alcaligenes sp. strain PKS1 and Bacillus sp. strain PSS2 were selected to establish a plant growth promoting bacterial consortium named PGPBc, which was then tested to determine its effectiveness in facilitating saltgrass seed germination and growth both in vitro and in contaminated soil. The results showed that PGPBc inoculation had no significant effect on the germination of saltgrass seeds, but had significantly positive effect on plant biomass production in contaminated soil covered with a surface layer of potting soil. PGPBc inoculation increased plant biomass in sterilized soil by 4-fold and in unsterilized soil by 6.6-fold. In this study, we reported the phosphate solubilization ability of Serratia proteamaculans, and demonstrated the use of PGPBc for promoting saltgrass growth in hydrocarbon contaminated soil.

Remotely piloted aerial application systems (RPAAS) are exponentially increasing globally for pesticide applications. Evaluations of spray coverage, deposits, and droplet size, when implementing various application parameters, are needed to optimize these applications. A RPAAS at 46.8 L ha-1 provided similar or greater coverage and deposits to ground equipment at 93.5 L ha-1 across nozzle types evaluated excluding the XR. The RPAAS at 18.7 L ha-1 had reduced coverage (<9% total coverage) and deposits (<350 total deposits cm-2) regardless of nozzle type evaluated compared to the other two application setups. The top and back WSP locations had considerably greater coverage and deposits than the front WSP location likely due to wind speed and direction being more important drivers for spray dynamics than direction of sprayer travel. Generally, nozzle selection was less critical for coverage and deposits from RPAAS at 18.7 L ha-1. The AITTJ60, AIXR, and TADF nozzle types may be optimum options for RPAAS, particularly at 46.8 L ha-1, as they improved coverage, deposits, and estimated recovery rate while producing the greatest droplet size, thereby reducing spray drift potential. Results of this research demonstrated coverage, deposits, and droplet size from RPAAS at 46.8 L ha-1 can be equivalent to ground spray equipment at 93.5 L ha-1 across a range of nozzle types and therefore, may be viable for effective pesticide applications. Applications using RPAAS at 18.7 L ha-1 resulted in considerably less coverage and deposits across nozzle types evaluated, and would be at risk for reduced pesticide efficacy. [ABSTRACT FROM AUTHOR]

This research is part of a multidisciplinary research program to develop a bioremediation protocol for a solid waste management (SWM) site in Northern California - a site which is heavily contaminated with petroleum hydrocarbons. In this initial study, 30 bacterial strains were isolated and evaluated for their efficiencies to deplete crude oil. The 3 most efficient bacterial isolates for crude oil depletion were designated as S1BD1, OPKDS2, and OSDS1; they were identified as Serratia proteamaculans, Alcaligenes sp. and Rhodococcus erythropolis, respectively, based on partial 16S rRNA gene sequences. Determination of crude oil depletion efficiency by gas chromatography–mass spectrometry (GC-MS) revealed that Serratia proteamaculans S1BD1 was the most efficient (68.0 ± 1.78%), followed by Alcaligenes sp. OPKDS2 (63.7 ± 3.28%), and Rhodococcus erythropolis OSDS1 (54.9 ± 5.07%). S. proteamaculans S1BD1 was able to deplete a wide spectrum of carbon compounds within the individual components of crude oil. Alcaligenes sp. OPKDS2 was the most efficient at depleting BTEX (91.2 ± 1.90%), and R. erythropolis OSDS1 exhibited a substrate preference of n-alkanes. All three strains exhibited unusually high crude oil depletion efficiencies and tolerated a wide range of salinity and pH levels, which makes them excellent candidates for bioaugmentation of the SWM site.