Model Predictive BESS Control for Demand Charge Management and PV-Utilization Improvement

Adoption of battery energy storage systems for behind-the-meters application offers valuable benefits for demand charge management as well as increasing PV-utilization. The key point is that while the benefit/cost ratio for a single application may not be favorable for economic benefits of storage systems, stacked services can provide multiple revenue streams for the same investment. Under this framework, we propose a model predictive controller to reduce demand charge cost and enhance PV-utilization level simultaneously. Different load patterns have been considered in this study and results are compared to the conventional rule-based controller. The results verified that the proposed controller provides satisfactory performance by improving the PV-utilization rate between 60% to 80% without significant changes in demand charge (DC) saving. Furthermore, our results suggest that batteries can be used for stacking multiple services to improve their benefits. Quantitative analysis for PV-utilization as a function of battery size and prediction time window has also been carried out.Comment: Accepted in: Conference on Innovative Smart Grid Technology (ISGT), Washington, DC, 201

Determination of ultimate load and possible failure path for solid continuous media using adaptive refinement process

AbstractIn this study, an effective and practical, h-version, enrichment mesh generation, and finite element adaptive procedure for the non-linear solution of problems in continuous media is presented. Moreover, based on the gradient recovery rule, a general recovery technique is developed to measure error and refine mesh in general finite element solutions. The recovery technique is simple and cost effective to implement. The technique has been formulated for two dimensional problems by employing triangular elements. The formulation is consistent with non-linear formulations which iteratively equilibrate the continuous media problems.In the present study, in addition to correlating various norms (such as energy norm, L2 norm for stress and L2 norm for strain), a new norm, namely, deviating stresses norm (called J norm in this study), is also correlated by the authors to estimate the error rate in the finite element method. Based on the results of this study, the J norm can be used as a tool to estimate the error rate in the finite element method, and to determine the ultimate load and the possible failure path in continuous domains. For several numerical examples, the developed algorithms are demonstrated and the resulting meshes are presented

Arbuscular Mycorrhizas Reduce Nitrogen Loss via Leaching

The capacity of mycorrhizal and non-mycorrhizal root systems to reduce nitrate (NO3−) and ammonium (NH4+) loss from soils via leaching was investigated in a microcosm-based study. A mycorrhiza defective tomato mutant and its mycorrhizal wildtype progenitor were used in this experiment in order to avoid the indirect effects of establishing non-mycorrhizal control treatments on soil nitrogen cycling and the wider soil biota. Mycorrhizal root systems dramatically reduced nitrate loss (almost 40 times less) via leaching, compared to their non-mycorrhizal counterparts, following a pulse application of ammonium nitrate to experimental microcosms. The capacity of AM to reduce nutrient loss via leaching has received relatively little attention, but as demonstrated here, can be significant. Taken together, these data highlight the need to consider the potential benefits of AM beyond improvements in plant nutrition alone

Karyological study of the medicinal plant Papaver rhoeas from northwest of Iran

Karyotype and morphology of mitotic chromosomes in six populations of the medicinal plant Papaver rhoeas collected from various geographical locations of the northwest of Iran were studied. Chromosome characteristics were measured from 10 complete metaphase cells using micromeasure software. The results showed that P. rhoeas is a diploid species with 2n=2x=14 chromosomes. The karyotype consisted of seven pairs of submetacentric chromosomes with one pairs of SAT chromosome (chromosome 2) having a secondary constriction at the end of its short arm. Karyological characteristics of all the materials studied were similar to each other; however, there were some variations on chromosome arm ratios and relative lengths among the different populations. All of the populations are placed on 4A class of Stebbin’s asymmetry categories.Key words: Biodiversity, chromosome analysis, medicinal plants, Papaveraceae

SECTAR: Model for economically optimal sustained groundwater yield planning

This paper presents an approach for computing economically optimal sustained yield ground-water extract ion strategies and supportable irrigated crop acreages. Computed regional strategies maximize the present value of net economic return_ They are useful for long-term agricultural planning because they are sustainable even beyond the planning period considered within the economic optimization. The hybrid approach uses only steady-state flow equations and iterative simulation/optimization to reduce optimization memory requirements below that required by conventional models utilizing both steady and unsteady equations. SECTAR, a quadratic optimization planning model assumes heads will evolve toward optimal steady-state but does initially not know the nonlinear rates of evolution in each cell. Rates of change in head are assumed, and optimization is performed. Subsequently, a linear or nonlinear simulation model computes actual time-varying rates of head change that would result from implementing the optimal strategy. Rates of change assumed in the optimization model are then corrected to correspond to simulated values. The process of assuming head-change rates, computing optimal pumping and eventual steady-state head values, and then simulating is repeated. Assumed and simulated heads are effectively the same within three or four cycles. Convergence occurs because of their common tendency to evolve to steady state. The procedure is applicable for situations of constant or time-varying transmissivity. Strategies developed for regions with initially stressed and unstressed potentiometric surfaces are compared. Evolution toward target steady-s,tate conditions and sensitivity of strategies to aquifer and economic parameters is presented

In vitro propagation of four Iranian grape varieties: Influence of genotype and pretreatment with arbuscular mycorrhiza

There is a great demand for table grape saplings, mainly for commercial varieties indicating that micropropagation could be an effective method for their mass propagation. Internal contamination in woody plant species is an important problematic issue and arbuscular mycorrhizal fungi (AMF) have been known as potential plant biological protectors. In the present study, the glasshouse grown mother plants of four grape varieties ('Asgari', 'Khalili', 'Keshmeshi', and 'Shahroudi') were inoculated with AMF as pre-treatment. The fungi strains were Glomus mosseae, G. fasciculatum, G. intraradices and a mixture of all three species. The comparative in vitro performance of these genotypes was evaluated following optimization of in vitro growth conditions for each genotype. Furthermore, the positive effect of AMF inoculation of stock plant on micropropagation process was studied. Changes in biochemical features (total chlorophylls, total phenols and total sugars), growth parameters (root length and total leaf area) and in vitro behavior of AMF pretreated as well as control explants were recorded. The mycorrhizal association with grapevine roots was confirmed following root staining and evaluation of colonization rate. The results revealed a distinct difference and clear genotypic effect on various in vitro parameters of studied grape genotypes. The utilized inocula were found to have the capability of mycorrhizal association with grapevine roots, leading to enhancing phenolics as a defense mechanism, increasing sugars and chlorophyll and finally growth of whole plant corresponding to the grape variety and AMF strain. These results confirmed that health and physiological conditions of the stock plants are important parameters for in vitro grape culture establishment and suggest the integration of mycorrhizal technology with tissue culture to accomplish better results

Assortative human pair-bonding for partner ancestry and allelic variation of the dopamine receptor D4 (DRD4) gene

The 7R allele of the dopamine receptor D4 gene has been associated with attention-deficit hyperactivity disorder and risk taking. On the cross-population scale, 7R allele frequencies have been shown to be higher in populations with more of a history of long-term migrations. It has also been shown that the 7R allele is associated with individuals having multiple-ancestries. Here we conduct a replication of this latter finding with two independent samples. Measures of subjects’ ancestry are used to examine past reproductive bonds. The individuals’ history of inter-racial/ancestral dating and their feelings about this are also assessed. Tentative support for an association between multiple ancestries and the 7R allele were found. These results are dependent upon the method of questioning subjects about their ancestries. Inter-racial dating and feelings about inter-racial pairing were not related to the presence of the 7R allele. This might be accounted for by secular trends that might have substantively altered the decision-making process employed when considering relationships with individuals from different groups. This study provides continued support for the 7R allele playing a role in migration and/or mate choice patterns. However, replications and extensions of this study are needed and must carefully consider how ancestry/race is assessed

Fuzzy Characterization of Near-Earth-Asteroids

Due to close encounters with the inner planets, Near-Earth-Asteroids (NEAs) can have very chaotic orbits. Because of this chaoticity, a statistical treatment of the dynamical properties of NEAs becomes difficult or even impossible. We propose a new way to classify NEAs by using methods from Fuzzy Logic. We demonstrate how a fuzzy characterization of NEAs can be obtained and how a subsequent analysis can deliver valid and quantitative results concerning the long-term dynamics of NEAs.Comment: 11 pages, presented at the 7th Alexander von Humboldt Colloquium on Celestial Mechanics (2008), accepted for publication in "Celestial Mechanics and Dynamical Astronomy