Teaching a traditional Korean art form : descriptive analyses of individual lessons taught by three gayageum sanjo master teachers

The present study represents the first systematic description of music teaching by gayageum sanjo masters. I observed and made video recordings of three renowned masters of sanjo who were teaching lessons to advanced-level students. I organized my descriptions around rehearsal frames, intervals of instructional time devoted to the accomplishment of identifiable proximal performance goals. Many of the characteristics of the teaching I observed are consistent with those identified in the teaching of artist-level Western musicians. Teachers strategically identified proximal performance goals that could be accomplished within brief time intervals and with few repetitions by the student. Thus, students consistently experienced successful outcomes throughout each lesson. As the students were performing at an advanced level and had already learned and could play the pieces they were working on, teachers were particularly focused on refining elements of musical expression and inflection. Perhaps as a result of this focus, teacher vocal and instrumental modeling were prominent features of all three lessons. Seldom did teachers address an aspect of student performance without providing some form of model. Data from these observations may provide a useful starting place for the formal study and further development of gayageum sanjo pedagogy.Musi

Comparing The Effectiveness Of Processing Instruction And Production-Based Instruction On L2 Grammar Learning: The Role Of Explicit Information

This article reports on a study that investigated whether processing instruction (PI) or production-based instruction (PBI) is more effective for the teaching of regular past simple verb forms in English. In addition, this study examined whether explicit grammatical information (EI) mediates the effectiveness of PI or PBI. A total of 194 Turkish EFL students were randomly assigned to one of the four experimental groups-PI+EI, PI-EI; PBI+EI, PBI-EI-or a control group and then completed interpretation and production tasks. The results demonstrated that (a) the PI-EI group and PBI-EI group performed equally well on both interpretation and production tasks; (b) when EI was a factor, the PI+EI group outperformed the PBI+ EI group on only the interpretation task, while no significant difference was found on the production task; (c) no significant differences were found between the PI+EI or -EI groups, and the PBI+ EI or -EI groups. Pedagogical implications of these findings are discussed, and suggestions made for future research

Comparing the Effectiveness of Processing Instruction and Production-Based Instruction on L2 Grammar Learning:The Role of Explicit Information

This article reports on a study that investigated whether processing instruction (PI) or production-based instruction (PBI) is more effective for the teaching of regular past simple verb forms in English. In addition, this study examined whether explicit grammatical information (EI) mediates the effectiveness of PI or PBI. A total of 194 Turkish EFL students were randomly assigned to one of the four experimental groups-PI+EI, PI-EI; PBI+EI, PBI-EI-or a control group and then completed interpretation and production tasks. The results demonstrated that (a) the PI-EI group and PBI-EI group performed equally well on both interpretation and production tasks; (b) when EI was a factor, the PI+EI group outperformed the PBI+ EI group on only the interpretation task, while no significant difference was found on the production task; (c) no significant differences were found between the PI+EI or -EI groups, and the PBI+ EI or -EI groups. Pedagogical implications of these findings are discussed, and suggestions made for future research

Multiantenna Downlink Interference Management for Next Generation Mobile Networks

Department of Electrical EngineeringIn downlink multi-input single-output (MISO) networks, achieving optimal sum-rate with limited channel state information (CSI) is still a challenge even with a single user per cell. In this dissertation, three cooperative downlink multicell MISO beamforming schemes are proposed with highly limited information exchange among the base stations (BSs) to maximize the sum-rate. In the proposed schemes, each BS can design its beamforming vector with only local CSI based on limited information exchange on CSI. Unlike previous studies, the proposed beamforming designs are non-iterative and do not require any vector or matrix feedback but require only quantized scalar information. In the first work, the beamforming vector at each BS is designed to minimize the sum of its weighted generating-interference (WGI) with local CSI and the aid of information exchange between the BSs. The generating-interference weight coefficients are designed in pursuit of increasing the sum-rate. Simulation results show that the proposed scheme outperforms the existing scheme in the mid to high signal-to-noise ratio (SNR) regime even with much reduced amount of information exchange via backhaul. In the second work, the proposed beamforming design is based on the combination of the maximization of weighted signal-to-leakage-plus-noise ratio (WSLNR) and WGI. The weights in WSLNR and WGI are designed via choosing a proper set of users who shall be interference-free, which has never been endeavored in the literature. Though there have been extensive studies on downlink multicell beamforming, the proposed scheme closely achieves the optimal sum-rate bound in almost all SNR regime based on non-iterative optimization with lower amount of information exchange than existing schemes, which is justified by numerical simulations. In addition, the proposed scheme achieves a better trade-off between the amount of the information exchange and the sum-rate than existing schemes. In the third work, a beamforming vector design based on a deep neural network (DNN) is proposed for multicell multi-input single-output channels with scalar information exchange and local CSI. The beamforming vectors are designed making zero generating-interference to the selected interference-free users (IFUs). The set of IFUs is chosen from the DNN based on supervised learning where the inputs can be obtained with only local CSI and limited scalar information exchange. Simulation results show that the DNN is well-trained in estimating the unknown CSI from the inputs with only local CSI in multicell networks.clos

Wind Turbine Airfoil Boundary Layer Optimization Using Genetic Algorithm with 3D Rotational Augmentation

The airfoil shape of horizontal axis wind turbine (HAWT) blade is optimized using genetic algorithm (GA). The algorithm is set to find the final airfoil shape with the highest gliding ratio (GR) and larger laminar boundary layer regime along the airfoil surface. The main aim is to find the best airfoil shape of higher lift coefficient with reduced drag in boundary layer from the reference airfoil shape. A 3D correction law is applied to model the effect of optimized airfoil in 3D rotational augmented situation. The thrust and power curves are generated by the blade element (BEM) and free vortex (FV) codes with 3D and loss correction. The higher power production is given when the wind turbine blades are designed using the optimized airfoil. This increment is thought to be made from the efficiency caused by the reduced separation bubbles from reduced turbulent boundary layer and 3D rotational augmentation. To validate its effectiveness in case of soiled condition, the aerodynamic parameters of airfoils are recalculated by enforcing the airfoil to undergo earlier transition, which models the leading edge roughness. The results indicate the soiled condition that does not affect the aerodynamic efficiency of the airfoil due to the positive effect of 3D rotation augmentation

Airfoil Boundary Layer Optimization Toward Aerodynamic Efficiency of Wind Turbines

This chapter describes the method of airfoil optimization considering boundary layer for aerodynamic efficiency increment. The advantages of laminar boundary layer expansion in airfoil of horizontal axis wind turbine (HAWT) blades are presented as well. The genetic algorithm (GA) optimization interfaced with the flow solver XFOIL was used with multi-objective function. The power performance of turbine with optimized airfoil was calculated by using blade element method (BEM) in software QBlade. The CFD simulation from OpenFOAM® with Spalart-Allmaras turbulence model showed the visualized airflow. The optimized airfoil shows enlarged laminar boundary layer region in all flow regime with a higher aerodynamic efficiency and the increased gliding ratio (GR). The power velocity and annual energy production (AEP) curves show the performance improvement of wind turbine with the optimized airfoil. The boundary layer thickness and skin-friction coefficient values support the decreased drag of the optimized airfoil. The smaller laminar separation bubbles and reduced stall regime of CFD simulations illustrate the desirable aerodynamics of the resulted airfoil

Enhanced terahertz conductivity in ultra-thin gold film deposited onto (3-mercaptopropyl) trimethoxysilane (MPTMS)-coated Si substrates

Various material properties change considerably when material is thinned down to nanometer thicknesses. Accordingly, researchers have been trying to obtain homogeneous thin films with nanometer thickness but depositing homogeneous few nanometers thick gold film is challenging as it tends to form islands rather than homogenous film. Recently, studies have revealed that treating the substrate with an organic buffer, (3-mercaptopropyl) trimethoxysilane (MPTMS) enables deposition of ultra-thin gold film having thickness as low as 5 nm. Different aspects of MPTMS treatment for ultrathin gold films like its effect on the structure and optical properties at visible wavelengths have been investigated. However, the effect of the MPTMS treatment on electrical conductivity of ultra-thin gold film at terahertz frequency remains unexplored. Here, we measure the complex conductivity of nanometer-thick gold films deposited onto an MPTMS-coated silicon substrate using terahertz time-domain spectroscopy. Following the MPTMS treatment of the substrate, the conductivity of the films was found to increase compared to those deposited onto uncoated substrate for gold films having the thickness less than 11 nm. We observed 5-fold enhancement in the conductivity for a 7 nm-thick gold film. We also demonstrate the fabrication of nanoslot-antenna arrays in 8.2-nm-thick gold films. The nanoslot-antenna with MPTMS coating has resonance at around 0.5 THz with an electric field enhancement of 44, whereas the nanoslot-antenna without MPTMS coating does not show resonant properties. Our results demonstrate that gold films deposited onto MPTMS-coated silicon substrates are promising advanced materials for fabricating ultra-thin terahertz plasmonic devices

Extended crossover from Fermi liquid to quasi-antiferromagnet in the half-filled 2D Hubbard model

The ground state of the Hubbard model with nearest-neighbor hopping on the square lattice at half filling is known to be that of an antiferromagnetic (AFM) band insulator for any on-site repulsion. At finite temperature, the absence of long-range order makes the question of how the interaction-driven insulator is realized nontrivial. We address this problem with controlled accuracy in the thermodynamic limit using self-energy diagrammatic determinant Monte Carlo and dynamical cluster approximation methods and show that development of long-range AFM correlations drives an extended crossover from Fermi liquid to insulating behavior in the parameter regime that precludes a metal-to-insulator transition. The intermediate crossover state is best described as a non-Fermi liquid with a partially gapped Fermi surface.Comment: 6 pages, 4 figures, with supplemental material: 2 pages, 3 figure

韓国人日本語学習者による句末イントネーションの生成と知覚

筑波大学 (University of Tsukuba)201