Graduate Recital:Mun Soo Kim, Piano

Kemp Recital Hall Saturday Evening April 26, 200

Selective Kernel Attention for Robust Speaker Verification

Recent state-of-the-art speaker verification architectures adopt multi-scale processing and frequency-channel attention techniques. However, their full potential may not have been exploited because these techniques' receptive fields are fixed where most convolutional layers operate with specified kernel sizes such as 1, 3 or 5. We aim to further improve this line of research by introducing a selective kernel attention (SKA) mechanism. The SKA mechanism allows each convolutional layer to adaptively select the kernel size in a data-driven fashion based on an attention mechanism that exploits both frequency and channel domain using the previous layer's output. We propose three module variants using the SKA mechanism whereby two modules are applied in front of an ECAPA-TDNN model, and the other is combined with the Res2Net backbone block. Experimental results demonstrate that our proposed model consistently outperforms the conventional counterpart on the three different evaluation protocols in terms of both equal error rate and minimum detection cost function. In addition, we present a detailed analysis that helps understand how the SKA module works.Comment: Submitted to INTERSPEECH 2022. 5 pages, 3 figures, 1 tabl

Fully Unsupervised Training of Few-shot Keyword Spotting

For training a few-shot keyword spotting (FS-KWS) model, a large labeled dataset containing massive target keywords has known to be essential to generalize to arbitrary target keywords with only a few enrollment samples. To alleviate the expensive data collection with labeling, in this paper, we propose a novel FS-KWS system trained only on synthetic data. The proposed system is based on metric learning enabling target keywords to be detected using distance metrics. Exploiting the speech synthesis model that generates speech with pseudo phonemes instead of texts, we easily obtain a large collection of multi-view samples with the same semantics. These samples are sufficient for training, considering metric learning does not intrinsically necessitate labeled data. All of the components in our framework do not require any supervision, making our method unsupervised. Experimental results on real datasets show our proposed method is competitive even without any labeled and real datasets.Comment: Accepted by IEEE SLT 202

Use of national folk music in a style utilizing original and modern procedures: a case study of Korean contemporary art music 16 arirang variations for piano solo by Bahk Jun Sang

The present document addresses the ways intercultural music emerged and intensified in Korea in historic and musical developments since the introduction of Western music in the late nineteenth century, and to provide a theoretical analysis of 16 Arirang Variations for piano solo by Bahk Jun Sang; hopefully pianists and music scholars may benefit from understanding the role of national folk music and its incorporation into modern Western musical styles as the most notable features in this composition. Among many Korean contemporary composers, Bahk Jun Sang (b. 1937) has contributed to the development of this new trend to blend national identity with more contemporary innovations. His work, 16 Arirang Variations for piano (1985), is a musical exploration of a spectrum of styles combining authentic folk elements with more avant-garde developments. For a better understanding of the work, biographical information on the composer and a theoretical analysis of this work is included in this document. Through studying the characteristics of each variation performers can present a more informed interpretation of the piece. Another goal in this study was to present detailed and comprehensive information on the development of Korean art music in the course of the twentieth century, which will benefit scholars and performers alike given the current increase of importance in a growing Asian contribution to the body of art music once almost exclusively Western. Ater the introductory Chapter I, Chapter II describes the development of the musical acculturation in Korea in the twentieth century to provide readers with a better understanding of the historical background of the work. The chapter continues with an examination of musical approaches which combine modern musical idioms and national folk music. Since Korean folk music plays an essential role in this work, some knowledge of traditional Korean folk music is included. Chapter III examines the role of folk music in the musical synthesis, featuring the incorporation of folk music into an intercultural blend of Eastern and Western art music. The remainder of Chapter III describes detailed features, including historical background and musical characteristics of Arirang, the Korean folk song which is used in 16 Arirang Variations. Chapter IV contains a brief biographical sketch of Bahk Jun Sang, and, most importantly, a theoretical analysis which details and explains the musical blend of Korean folk music and Western-style techniques in Bahk's 16 Arirang Variations for piano

Lichen Striatus Occurring after Allogenic Peripheral Blood Stem Cell Transplantation in an Adult with Aplastic Anemia

Lichens striatus (LS) is an acquired, self-limiting inflammatory dermatosis that follows the lines of Blaschko. The etiology of the eruption is unknown, but several theories have been proposed with focus on environmental factors, viral infection, cutaneous injury, hypersensitivity, and genetic predisposition. We describe a 19-year-old woman who developed a unilateral linear eruption 17 months after allogenic peripheral blood stem cell transplantation. Histopathology revealed features, which were consistent with LS. To the best of our knowledge, our patient is the first case describing the appearance of LS occurring after allogenic stem cell transplantation. We speculate that this condition represents an unusual form of localized, chronic graft-versus-host disease

Operational issues on Gas Turbine combustors for a Combined Cycle Power Plant

ABSTRACT Combined cycle gas turbine (CCGT) power plant is one of the cleanest and most efficient ways for fossil fuel power generation. A CCGT system uses the technologies of gas turbines and steam turbines to produce electricity more effectively than can be achieved using either of these technologies separately. Lean premixed flame is agreed to be the state-of-the-art technology for power plant gas turbines due to its great efficiency and especially low NOx emission. Despite of the high system efficiency and low harmful exhaust gases, there have been technical issues called "combustion instability" in the lean premixed gas turbine combustors, which are the feedback relationships between heat release oscillations and pressure wave perturbations. In this paper, the operational issues of the lean premixed combustor including the combustion instabilities and its basic mechanisms were explained

Treatment of Two Level Artificial Disc Replacement for Cervical Spondylotic Myelopathy

Cervical spondylotic myelopathy (CSM) is a common spinal disorder caused by compression of the spinal cord, due to degeneration of the cervical spine. We investigated post-operative results and suggest artificial disc replacement (ADR) as an effective surgical method for treating CSM. We present the case of a 36-year-old man, with nuchal pain; severe paresthesia of both upper and lower extremities; and pain, motor weakness, and difficulty in fine motor control of both hands. A cervical X-ray showed spondylotic changes at the C5-6, C6-7 level and MRI revealed cord compression at the C5-6, C6-7 level. ADR was performed at the C5-6, C6-7 level. After the surgery, the motor weakness of both upper extremities and paresthesia of both aspects improved. In addition, the JOA score and Nurick grade improved. A post-operative X-ray showed well positioned instruments, and post- operative MRI displayed no lesions of cord compression. Anterior cervical discectomy and fusion (ACDF) is widely accepted as a leading treatment for CSM, but ACDF may cause adjacent segment disease (ASD). We suggest that ADR also can represent a good surgical procedure for the management of multilevel spinal cord compression, as it can preserve cervical motion while avoiding AS