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Hafen, Ryan P

Publications and source records attributed to Hafen, Ryan P.

Challenges in Biomarker Discovery: Combining Expert Insights with Statistical Analysis of Complex Omics Data

The advent of high throughput technologies capable of comprehensive analysis of genes, transcripts, proteins and other significant biological molecules has provided an unprecedented opportunity for the identification of molecular markers of disease processes. However, it has simultaneously complicated the problem of extracting meaningful signatures of biological processes from these complex datasets. The process of biomarker discovery and characterization provides opportunities both for purely statistical and expert knowledge-based approaches and would benefit from improved integration of the two. Areas covered In this review we will present examples of current practices for biomarker discovery from complex omic datasets and the challenges that have been encountered. We will then present a high-level review of data-driven (statistical) and knowledge-based methods applied to biomarker discovery, highlighting some current efforts to combine the two distinct approaches. Expert opinion Effective, reproducible and objective tools for combining data-driven and knowledge-based approaches to biomarker discovery and characterization are key to future success in the biomarker field. We will describe our recommendations of possible approaches to this problem including metrics for the evaluation of biomarkers.

bioinformatics↗

Planning for Variable Generation Integration through Balancing Authorities Consolidation

As more and more variable generation is integrated into power grids, many challenges and concerns arise for an individual balancing authority (BA) to balance the system with limited resources. Consolidating balancing authorities provides a promising method to mitigate these problems by enabling the sharing of resources through operating different BAs as a single BA. The diversity in load and renewable generation over a wide area can be effectively leveraged, which makes it possible to achieve significant savings in balancing requirements. This paper develops a detailed procedure to compute savings in load following and regulation service requirements due to BAs consolidation. It proposes several evaluation metrics for demonstrating the benefits of BA consolidation. Several study scenarios are designed for a set of BAs in the western United States to test the proposed procedure. Results have shown significant savings in the capacity, ramp rate, and energy of balancing service requirements. Important factors affecting the savings, such as forecast accuracy and cross correlation between forecast errors, are also discussed.

Diao, Ruisheng↗

Speech information retrieval: a review

Audio is an information-rich component of multimedia. Information can be extracted from audio in a number of different ways, and thus there are several established audio signal analysis research fields. These fields include speech recognition, speaker recognition, audio segmentation and classification, and audio finger-printing. The information that can be extracted from tools and methods developed in these fields can greatly enhance multimedia systems. In this paper, we present the current state of research in each of the major audio analysis fields. The goal is to introduce enough back-ground for someone new in the field to quickly gain high-level understanding and to provide direction for further study.

Hafen, Ryan P↗