Linear-Gompertz Model-Based Regression of Photovoltaic Power Generation by Satellite Imagery-Based Solar Irradiance

A simple yet accurate photovoltaic (PV) performance curve as a function of satellite-based solar irradiation is necessary to develop a PV power forecasting model that can cover all of South Korea, where more than 35,000 PV power plants are currently in operation. In order to express the nonlinear power output of the PV module with respect to the hourly global horizontal irradiance derived from satellite images, this study employed the Gompertz model, which is composed of three parameters and the sigmoid equation. The nonphysical behavior of the Gompertz model within the low solar irradiation range was corrected by combining a linear equation with the same gradient at the conjoint point. The overall fitness of Linear-Gompertz regression to the 242 PV power plants representing the country was R2 = 0.85 and nRMSE = 0.09. The Gompertz model coefficients showed normal distributions and equivariance of standard deviations of less than 15% by year and by season. Therefore, it can be conjectured that the Linear-Gompertz model represents the whole country’s PV system performance curve. In addition, the Gompertz coefficient C, which controls the growth rate of the curve, showed a strong correlation with the capacity factor, such that the regression equation for the capacity factor could be derived as a function of the three Gompertz model coefficients with a fitness of R2 = 0.88.This work was conducted under the framework of the Research and Development Program of the Korea Institute of Energy Research (C0-2407)

Strategic Asset Allocation Of Credit Guarantors

How to manage the portfolio of credit guarantors is important in practice and public policy, but has not been investigated well in the prior literature. We empirically compare four different approaches in managing credit guarantor portfolios. The four approaches are equal weighted, minimum variance, mean variance optimization and equal risk contribution methods. In terms of risk return ratio, the mean variance optimization model performs best in out-of-sample test. This result contrasts with previous findings against mean variance optimization. Our results are robust. The results do not change as the characteristics of guarantee portfolio vary

Pruning Self-Attention for Zero-Shot Multi-Speaker Text-to-Speech

For personalized speech generation, a neural text-to-speech (TTS) model must be successfully implemented with limited data from a target speaker. To this end, the baseline TTS model needs to be amply generalized to out-of-domain data (i.e., target speaker's speech). However, approaches to address this out-of-domain generalization problem in TTS have yet to be thoroughly studied. In this work, we propose an effective pruning method for a transformer known as sparse attention, to improve the TTS model's generalization abilities. In particular, we prune off redundant connections from self-attention layers whose attention weights are below the threshold. To flexibly determine the pruning strength for searching optimal degree of generalization, we also propose a new differentiable pruning method that allows the model to automatically learn the thresholds. Evaluations on zero-shot multi-speaker TTS verify the effectiveness of our method in terms of voice quality and speaker similarity.Comment: INTERSPEECH 202

GS2PATH: A web-based integrated analysis tool for finding functional relationships using gene ontology and biochemical pathway data

GS2PATH is a Web-based pipeline tool to permit functional enrichment of a given gene set from prior knowledge databases, including gene ontology (GO) database and biological pathway databases. The tool also provides an estimation of gene set enrichment, in GO terms, from the databases of the KEGG and BioCarta pathways, which may allow users to compute and compare functional over-representations. This is especially useful in the perspective of biological pathways such as metabolic, signal transduction, genetic information processing, environmental information processing, cellular process, disease, and drug development. It provides relevant images of biochemical pathways with highlighting of the gene set by customized colors, which can directly assist in the visualization of functional alteration

Pepper EST database: comprehensive in silico tool for analyzing the chili pepper (Capsicum annuum) transcriptome

<p>Abstract</p> <p>Background</p> <p>There is no dedicated database available for Expressed Sequence Tags (EST) of the chili pepper (<it>Capsicum annuum</it>), although the interest in a chili pepper EST database is increasing internationally due to the nutritional, economic, and pharmaceutical value of the plant. Recent advances in high-throughput sequencing of the ESTs of chili pepper cv. Bukang have produced hundreds of thousands of complementary DNA (cDNA) sequences. Therefore, a chili pepper EST database was designed and constructed to enable comprehensive analysis of chili pepper gene expression in response to biotic and abiotic stresses.</p> <p>Results</p> <p>We built the Pepper EST database to mine the complexity of chili pepper ESTs. The database was built on 122,582 sequenced ESTs and 116,412 refined ESTs from 21 pepper EST libraries. The ESTs were clustered and assembled into virtual consensus cDNAs and the cDNAs were assigned to metabolic pathway, Gene Ontology (GO), and MIPS Functional Catalogue (FunCat). The Pepper EST database is designed to provide a workbench for (i) identifying unigenes in pepper plants, (ii) analyzing expression patterns in different developmental tissues and under conditions of stress, and (iii) comparing the ESTs with those of other members of the <it>Solanaceae </it>family. The Pepper EST database is freely available at <url>http://genepool.kribb.re.kr/pepper/</url>.</p> <p>Conclusion</p> <p>The Pepper EST database is expected to provide a high-quality resource, which will contribute to gaining a systemic understanding of plant diseases and facilitate genetics-based population studies. The database is also expected to contribute to analysis of gene synteny as part of the chili pepper sequencing project by mapping ESTs to the genome.</p

Overexpression of alfalfa mitochondrial HSP23 in prokaryotic and eukaryotic model systems confers enhanced tolerance to salinity and arsenic stress

The cloning and characterization of a gene (MsHSP23) coding for a heat shock protein in alfalfa in a prokaryotic and model plant system is described. MsHSP23 contains a 633 bp ORF encoding a polypeptide of 213 amino acids and exhibits greater sequence similarity to mitochondrial sHSPs from dicotyledons than to those from monocotyledons. When expressed in bacteria, recombinant MsHSP23 conferred tolerance to salinity and arsenic stress. Furthermore, MsHSP23 was cloned in a plant expressing vector and transformed into tobacco, a eukaryotic model organism. The transgenic plants exhibited enhanced tolerance to salinity and arsenic stress under ex vitro conditions. In comparison to wild type plants, the transgenic plants exhibited significantly lower electrolyte leakage. Moreover, the transgenic plants had superior germination rates when placed on medium containing arsenic. Taken together, these overexpression results imply that MsHSP23 plays an important role in salinity and arsenic stress tolerance in transgenic tobacco. This approach could be useful to develop stress tolerant crops including forage crops

The Bell Laboratories (13)CO Survey: Longitude-Velocity Maps

A survey is presented of the Galactic plane in the J=1-0 transition of (13)CO. About 73,000 spectra were obtained with the 7 m telescope at Bell Laboratories over a ten-year period. The coverage of survey is (l, b) = (-5 to 117, -1 to +1), or 244 square degrees, with a grid spacing of 3' for |b| < 0.5, and a grid spacing of 6' for |b| > 0.5. The data presented here have been resampled onto a 3' grid. For 0.68 km/s channels, the rms noise level of the survey is 0.1 K on the $T_R^*$ scale. The raw data have been transformed into FITS format, and all the reduction processes, such as correcting for emission in the reference positions, baseline removal and interpolation were conducted within IRAF using the FCRAO task package and additional programs. The reduced data are presented here in the form of longitude-velocity color maps at each latitude. These data allow identification and classification of molecular clouds with masses in excess of ~ 1,000 solar masses throughout the first quadrant of the Galaxy. Spiral structure is manifested by the locations of the largest and brightest molecular clouds.Comment: 23 pages, 7 figures, ApJS submitted (out of 41 frames of Figure4, only one is included becaue of size limit