Sound Demixing Challenge 2023 Music Demixing Track Technical Report: TFC-TDF-UNet v3

In this report, we present our award-winning solutions for the Music Demixing Track of Sound Demixing Challenge 2023. First, we propose TFC-TDF-UNet v3, a time-efficient music source separation model that achieves state-of-the-art results on the MUSDB benchmark. We then give full details regarding our solutions for each Leaderboard, including a loss masking approach for noise-robust training. Code for reproducing model training and final submissions is available at github.com/kuielab/sdx23.Comment: 5 pages, 4 table

Spatial Clustering based Meteorological Fields Construction for Regional Vulnerability Assessment

Chemical accidents have affected the social-environmental system. For the regional vulnerability assessment, which is the baseline work to assess the impact on the environment, a meteorological field is needed to determine how chemicals from multiple adjacent companies are propagated. In this study, we present the method of meteorological field based on the spatial cluster which is the main component of vulnerability assessment on regional chemical accident scenario. To integrate spatially dense chemical companies into a cluster, we adopt spatial clustering algorithms. Experiment result shows that DBSCAN-based approach reduces 80.5% total area of the meteorological field against brute-force algorithm, and shows good performance on the average of the overlap ratio, and utility ratio for clustering results

A Multi-Mode ULP Receiver Based on an Injection-Locked Oscillator for IoT Applications

This paper presents an ultra-low-power receiver based on the injection-locked oscillator (ILO), which is compatible with multiple modulation schemes such as on-off keying (OOK), binary frequency-shift keying (BFSK), and differential binary phase-shift keying (DBPSK). The receiver has been fabricated in 0.18-μm CMOS technology and operates in the ISM band of 2.4 GHz. A simple envelope detection can be used even for the demodulation of BFSK and DBPSK signals due to the conversion capability of the ILO from the frequency and phase to the amplitude. In the proposed receiver, a Q-enhanced single-ended-to-differential amplifier is employed to provide high-gain amplification as well as narrow band-pass filtering, which improves the sensitivity and selectivity of the receiver. In addition, a gain-control loop is formed in the receiver to maintain constant lock range and hence frequency-to-amplitude conversion ratio for the varying power of the BFSK-modulated receiver input signal. The receiver achieves the sensitivity of -87, -85, and -82 dBm for the OOK, BFSK, and DBPSK signals respectively at the data rate of 50 kb/s and the BER lower than 0.1% while consuming the power of 324 μW in total.1

Cost-benefit analysis of water source improvements through borehole drilling or rehabilitation: an empirical study based on a cluster randomized controlled trial in the Volta Region, Ghana.

BACKGROUND: Despite remarkable progress in water coverage improvements, diseases associated with poor water remain a considerable public health problem in many developing countries. OBJECTIVE: We aimed to estimate the costs and benefits of drilling or rehabilitating boreholes with handpumps in resource-poor settings and hard-to-reach areas. METHODS: Diarrheal reduction in the population was predicted on the basis of the empirical findings from a cluster randomized controlled trial. The full investment and estimated annual running costs were used to calculate the intervention costs. Direct economic benefits of avoiding child diarrheal disease, indirect economic benefits related to health improvements, and non-health benefits related to water improvement were estimated. One-way and multi-way sensitivity analyses were performed to determine the robustness of the findings. RESULTS: Our analysis found that the return on a US$1 investment was US$ 9.4 for borehole drilling and US$ 14.1 for borehole rehabilitation. Time savings were the main contributor, accounting for 68% of the benefits, followed by the economic benefits of averted child deaths, which contributed to 15% of the benefits. The sensitivity analyses suggested that improving water sources yields high returns under all circumstances, and that borehole rehabilitation is more efficient than borehole drilling. CONCLUSION: This study explicitly justifies increased investment in water improvement in rural areas and demonstrates the high returns of rehabilitating boreholes. We hope that this study will be used as evidence for informing the policy decisions of governments or international agencies regarding further investments in improved water coverage in rural areas and the selection of appropriately designed interventions

Interlayer orientation-dependent light absorption and emission in monolayer semiconductor stacks

Two-dimensional stacks of dissimilar hexagonal monolayers exhibit unusual electronic, photonic and photovoltaic responses that arise from substantial interlayer excitations. Interband excitation phenomena in individual hexagonal monolayer occur in states at band edges (valleys) in the hexagonal momentum space; therefore, low-energy interlayer excitation in the hexagonal monolayer stacks can be directed by the two-dimensional rotational degree of each monolayer crystal. However, this rotation-dependent excitation is largely unknown, due to lack in control over the relative monolayer rotations, thereby leading to momentum-mismatched interlayer excitations. Here, we report that light absorption and emission in MoS2/WS2 monolayer stacks can be tunable from indirect- to direct-gap transitions in both spectral and dynamic characteristics, when the constituent monolayer crystals are coherently stacked without in-plane rotation misfit. Our study suggests that the interlayer rotational attributes determine tunable interlayer excitation as a new set of basis for investigating optical phenomena in a two-dimensional hexagonal monolayer system.open115850sciescopu

Does Abdominal Obesity Accelerate the Effect of Hypertriglyceridemia on Impaired Fasting Glucose?

Purpose: This study sought to determine whether abdominal obesity is a risk factor for impaired fasting glucose (IFG) and hypertriglyceridemia and to verify whether moderate effect of abdominal obesity on the relationship between IFG and hypertriglyceridemia in Korea. Materials and Methods: Data from the Korean National Health and Nutrition Examination Survey was used for the analysis. The study population included 5,938 subjects aged 20 year old drawn from non-diabetic participants in a health examination survey. The subjects were classified according to the presence of abdominal obesity based on waist circumference, IFG based on their fasting blood glucose level, and hypertriglyceridemia on their fasting triglyceride. Results: The multivariate-adjusted odds ratios for the occurrence of hypertriglyceridemia were 2.91 in the abdominal obesity group as compared with the nonobesity group and 1.31 in subjects with IFG compared with the normoglycemia controls. Abdominal obesity was found to be positively moderated in the interaction between waist circumference and fasting blood sugar. Conclusion: The moderate effect between abdominal obesity and IFG contributes to the development of hypertriglyceridemia in Korea

Cultural Representations of Youth in 1960s-1970s South Korea

My dissertation analyzes the youth representations in 1960s and 1970s literature, popular music, film, and discourse using interdisciplinary research. Beyond the demographic category as a part of society, youth is a modern symbolic signifier; it has been politically or culturally separated from and opposed to the existing society, while it has integrated and represented the entire society in a way that appropriates the future of the society. Thus, the representation of youth can be defined as a society's constitutive exception and metonymy. In South Korea, which belatedly began modernization, the challenge of modern nation-building and various ideas about modernization were mainly submitted through representations of youth. These representations were also significant because they contained common sentiments and affects that were the remnants and scars of the compressed modernization. First, I demonstrate how the youth representations combined with the student vanguard concept reveal the postcolonial challenges of the localization of Western modernity and South Korea’s belated attempts to catch-up to the modernization of the Western world. Then, I explore the way popular music and films created a shared structure of feeling and imagined a united society at a time when the gaps between class and gender increased in South Korean society through an analysis of the changing representations of lower-class young men and poor young women. Finally, the last chapter reveals how the autobiographical memoirs of young female factory workers in the late 1970s changed the symbolic function of youth and raised the question about the artistic norm of literature by embodying common sentiments and breaking the student vanguard concept. Together, the youth representations in various media constitute the epistemological and affective landscape of the developmental dictatorship and provide a social imagination of contemporary South Korean society