Modern packaging design requires extensive signal integrity simulations in order to assess the electrical performance of the system. The feasibility of such simulations is granted only when accurate ...and efficient models are available for all system parts and components having a significant influence on the signals. Unfortunately, model derivation is still a challenging task, despite the extensive research that has been devoted to this topic. In fact, it is a common experience that modeling or simulation tasks sometimes fail, often without a clear understanding of the main reason. This paper presents the fundamental properties of causality, stability, and passivity that electrical interconnect models must satisfy in order to be physically consistent. All basic definitions are reviewed in time domain, Laplace domain, and frequency domain, and all significant interrelations between these properties are outlined. This background material is used to interpret several common situations where either model derivation or model use in a computer-aided design environment fails dramatically. We show that the root cause for these difficulties can always be traced back to the lack of stability, causality, or passivity in the data providing the structure characterization and/or in the model itself.
•A VUV-based AOP was successfully integrated with biofiltration on two different media.•Compared to biologically active zeolite, biologically active carbon filters showed a superior performance for ...CECs control.•VUV-based AOP drastically reduced the CECs load to biofiltration.•Media type markedly affected microbial composition in the biofilters.
This study explored process synergies attainable by integrating a vacuum ultraviolet-based advanced oxidation process with biofiltration. A comparison using granular activated carbon or granular zeolite as filtration media were examined in context of advanced wastewater treatment for potable reuse. Six biofiltration columns, three with granular activated carbon and three with granular zeolite, were operated in parallel and batch-fed daily with nitrified secondary effluent. After achieving a pseudo-steady state through the filter columns, vacuum ultraviolet treatment was applied as pre-treatment or as post-treatment, at two different applied energies (i.e., VUV-E1=1 kWh/m3 and VUV-E10=10 kWh/m3). Once granular activated carbon had transitioned to biologically activated carbon, as determined based on soluble chemical oxygen demand removal, adsorption was still observed as the main mechanism for contaminants of emerging concern and nitrate removal. Vacuum ultraviolet pre-treatment markedly improved contaminants of emerging concern removal through the integrated system, achieving 40% at VUV-E1 and 90% at VUV-E10. When applied as post-treatment to zeolite column effluents, VUV-E1 and VUV-E10 further increased contaminants of emerging concern removal by 20% and 90%, respectively. In the zeolite system, vacuum ultraviolet pre-treatment also increased soluble chemical oxygen demand removal efficiency, indicating that higher energy vacuum ultraviolet increased biodegradability. Total prokaryotes were two-fold more abundant in biologically activated carbon than in zeolite, with vacuum ultraviolet pretreatment markedly affecting microbial diversity, both in terms of richness and composition. Media type only marginally affected microbial richness in the biofilters but showed a marked impact on structural composition. No clear relationship between compositional structure and depth was observed.
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Phenol and o-cresol have been shown to undergo oxygen-induced polymerization reactions on activated carbon that enhance their adsorption. Results from equilibrium and kinetics studies indicate that ...for both phenol and o-cresol, the adsorptive capacities increase with the increase in dissolved oxygen concentration.
High‐throughput sequencing (HTS) technologies have revolutionized plant pest research and are now raising interest for plant pest diagnostics, with plant virus diagnostics at the forefront of ...development. However, the application of HTS in plant pest diagnostics raises important challenges that plant health regulators will have to address. Adapted infrastructures, technical guidelines and training are pivotal for further use and adoption of the HTS technologies in the phytosanitary framework.
Technologies de séquençage génétique à haut débit pour le diagnostic des organismes nuisibles aux végétaux: défis et perspectives
Les technologies de séquençage génétique à haut débit ont révolutionné la recherche des organismes nuisibles aux végétaux et suscitent maintenant de l'intérêt dans le contexte de leur diagnostic, avec au premier plan celui des virus des végétaux. Cependant, l'application de ces technologies au diagnostic des organismes nuisibles aux végétaux fait émerger de nombreux challenges auxquels les personnes développant la réglementation en santé des végétaux devront faire face. Des infrastructures adaptées, des lignes directrices techniques ainsi que la formation sont des éléments clefs pour l'utilisation future et l'adoption de ces technologies dans le contexte phytosanitaire.
Пpимeнeниe тexнoлoгий выcoкoпpoизвoдитeльнoгo ceквeниpoвaния для диaгнocтики вpeдныx для pacтeний opгaнизмoв: cyщecтвyющиe пpoблeмы и oткpывaющиecя вoзмoжнocти
Texнoлoгии пиpoceквeниpoвaния (HTS) пoдняли нa кaчecтвeннo нoвый ypoвeнь иccлeдoвaния вpeдныx для pacтeний opгaнизмoв, и в нacтoящee вpeмя oни пoвышaют интepec к вoпpocaм диaгнocтики вpeдныx opгaнизмoв. Пpи этoм диaгнocтикa виpycoв pacтeний явлeтcя oднoй из пpиopитeтныx зaдaч. Oднaкo пpимeнeниe HTS для диaгнocтики вpeдныx для pacтeний opгaнизмoв coпpяжeнo c цeлым pядoм вaжныx пpoблeм, нa кoтopыe дoлжнo быть oбpaщeнo внимaниe нopмaтивныx opгaнoв фитocaнитapии. Boт пoчeмy для дaльнeйшeгo иcпoльзoвaния и пpинятия нa вoopyжeниe тexнoлoгий пиpoceквeниpoвaния (HTS) в фитocaнитapныx cтpyктypax нeoбxoдимa иx aдaптaция, coглacoвaнныe pyкoвoдящиe пpинципы и тpeнинг.
The impact of waste strength on the treatability of toxic wastes such as coal gasification wastewater by the anaerobic GAC reactor operating with periodic GAC replacement was assessed by operating ...three units treating 30%, 60% and full strength wastewater. At a COD loading of 4.7 kg/m
3 d performance was unimpacted by dilution at all the GAC replacement rates investigated in this study to define the minimum adsorptive capacity required to overcome the wastewater toxicity, with all three reactors achieving over 94% COD removal, more than 99.9% phenol removal, 98–99% cresols removal, and virtually complete removal of dimethyl phenols. The full strength wastewater was not treatable at COD loading rates higher than 10 kg/m
3 d while the reactors treating the diluted wastewater maintained a COD removal efficiency of about 90% and over 99.5% reduction of phenolic compounds at a loading of 32–34 kg COD/m
3 d. At this loading with a biological solids residence time of less than 21 d and hydraulic retention times of 4–8 h, biological activity was not affected at all by the toxicity of the waste.
The impact of anaerobic biological activity on the capacity of granular activated carbon (GAC) to adsorb organic compounds has not received much attention. In this study, the capacities of GAC for ...o-cresol obtained from bottle-point isotherm experiments were compared with the capacities measured in a completely mixed, biologically active, anaerobic GAC reactor treating a high-strength synthetic wastewater containing acetic acid, phenol, and o-cresol. O-cresol was not bio-degraded in the reactors and was removed solely by adsorption. Because of the low concentrations of phenol measured in the effluents from the reactors, no competition for adsorption between phenol and o-cresol was observed. Also, the role of biological activity in the regeneration of GAC was demonstrated by preloading GAC with phenol and recovering the adsorbed phenol after the establishment of an active bacterial film on the GAC surface.
With the industrial development and urban construction in Madinat Al-Jubail Alsinaiya in Saudi Arabia, which has mostly arid regions and due to limited water resources depends on diminishing ground ...water and costly desalinated seawater, wastewater reuse is pursued using reclaimed municipal and industrial wastewater through treatment plants.
This paper is an actual case study discussing the features of reuse, the processes used and the standards adopted. The effect of reuse upon the local environment is commented upon. This study also emphasizes the cost-competitiveness of wastewater reuse for irrigation in Saudi Arabia. Design data and operational results for the 19 MGD municipal wastewater water treatment plant and the 11 MGD industrial wastewater treatment plant will be discussed. Both plants utilize biological treatment followed by pressure filtration to meet the stringent standards governing the use of effluent in landscape irrigation. The effluent TDS, TSS, BOD
5 and SAR are valued 936, 4.4, 2.7, and 7.4, respectively, for the municipal wastewater treatment plant and 762, 2.1, 2.4 and 10.5, respectively, for the industrial wastewater treatment plant.
The impact of solution pH on the kinetics of adsorption and adsorption-reaction combination of phenol and o-cresol on Granular Activated Carbon (GAC) was evaluated at room temperature (21°C). Batch ...experiments were performed under oxic and anoxic conditions at pH values of 3, 7, and 11. The results showed that the equilibration time forphysical adsorption increased with the increase in pH and occurred in the time range of (7.5–11) days for the adsorption-reaction combination (oxic cases). The polymerization reactions lagged by about 10 h under all of the pH values. Diffusivity coefficients in the oxic cases increased inversely with pH while the highest difference between oxic and anoxic diffusivities was observed at neutral pH. The homogeneous surface diffusion model (HSDM) predicted accurately the anoxic batches and deviated from the oxic data under all pH conditions. Under controlled dissolved oxygen and pH conditions, the isotherm and batch equilibrium capacities matched with maximum deviation of 4%. The effect of solution pH on the rate of the DO-induced enhancement was found to follow a simplified form of self retardant reaction model. The aforementioned model showed strong predictive capability for the formation of polymers with time.
The increase of operating frequencies requires 3-D electromagnetic (EM) methods, such as the partial element equivalent circuit (PEEC) method, for the analysis and design of high-speed circuits. Very ...large systems of equations are often produced by 3-D EM methods and model order reduction (MOR) techniques are used to reduce such a high complexity. When signal waveform rise times decrease and the corresponding frequency content increases, or the geometric dimensions become electrically large, time delays must be included in the modeling. A PEEC formulation, which include delay elements called τ PEEC method, becomes necessary and leads to systems of neutral delayed differential equations (NDDE). The reduction of large NDDE is still a very challenging research topic, especially for electrically large structures, where delays among coupled elements cannot be neglected or easily approximated by rational basis functions. We propose a novel model order technique for τ PEEC models that is able to accurately reduce electrically large systems with large delays. It is based on an adaptive multipoint expansion and MOR of equivalent first-order systems. The neutral delayed differential formulation is preserved in the reduced model. Pertinent numerical examples based on τ PEEC models validate the proposed MOR approach.
A mathematical model for sequencing batch reactors (SBR) that takes into account fill and react periods was developed and tested against experimental data from the literature. The Monod equation was ...used to describe microbial growth kinetics. The proposed model predicts the time dependent microbial cell and substrate concentrations during SBR treatment of wastes. A numerical method was used to solve the governing model equations which comprised nonlinear unsteady-state ordinary differential equations. Model simulations highlighted the importance of feed rate as a major operating parameter. For biodegradable wastes and low strength inhibitory wastes, an instantaneous fill is optimum whereas high strength inhibitory waste treatment is only possible with long fill times. The model predictions compared well with experimental results reported in the literature. This model is useful for further understanding of biological wastewater treatment kinetics by batch processes and may serve as a valuable design aid for practicing engineers.
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