379 research outputs found
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The Post-Minimalist Symphony: Large-Scale Form in Music by John Adams, Philip Glass, and Aaron Jay Kernis
My thesis focuses on the materials and structure of the first movements of three large-scale symphonic works by prominent minimalist and post-minimalist composers. I selected these composers and their works because each indicates a different side of both minimalism and symphonic composition. First, John Adams’ Harmonielehre features the repeated chords typical of the minimalist style as well as repetitive motor rhythms, but they do not follow a strict repetition scheme. In addition, the structure of Harmonielehre is more appropriate to the sonata-allegro format of the first movement of a symphony compared to the other two works. Next, Philip Glass re-interpreted Low by David Bowie and Brian Eno with his signature minimalist/repetitive treatment but in an orchestral arrangement. Symphony No. 1 (“Low”) features surprising polytonal complexities, long subtle rhythmic cycles, and his most basic minimalist technique: the additive process. As in many other minimalist pieces, this piece exploits one form of continuity by slowly growing from a sparse rhythmic framework to a structure that also includes contrasting sections. Finally, the “Continuous Wave,” the first movement of Symphony in Waves, by Aaron Jay Kernis, makes use of another continuous form through an uninterrupted rhythmic pattern flowing from the beginning to the end of the first movement. As the youngest of the three composers, the influence of his teacher, John Adams, brings variety and dynamic energy to his music
Dynamic responses of base-isolated concrete liquid storage structure under two types of resonances
One important characteristic of base-isolated liquid storage structure (LSS) is that the vibration periods of structure and liquid are different, namely, there are two kinds of periods in the system. As a result, structure or liquid resonance may occurs under external excitation. In order to reflect the nonlinear characteristics of liquid sloshing, subsonic potential-based element is used to simulate the liquid. The governing equations of liquid field and fluid-structure interaction (FSI) equations are established; the initial and boundary conditions of liquid sloshing in dynamic coordinate system are obtained. Harmonic functions used to conduct time history analysis are generated by the first order vibration frequencies of structure and liquid respectively. The dynamic responses of base-isolated rectangular liquid storage structure (RLSS) under two types of resonance are studied comparatively. Results show that when the external excitation frequency is equal to the first order vibration frequency of isolated structure or liquid sloshing, wall tensile stress, structure displacement, base shear force and liquid sloshing wave height will appear resonance amplification phenomenon. The dynamic responses of structure itself caused by structure resonance are greater than that of liquid resonance; while the liquid sloshing wave height caused by liquid resonance is greater than that of structure resonance. Under structure resonance, the wall is prone to be cracked; and under liquid resonance, the liquid velocity field will become unusually violent, and liquid overflow will be caused easily
Seismic dynamic responses of earth-rock dam considering wave and seepage
Earth-rock dam plays an important role in water conservancy project, but there were many damage cases caused by earthquakes, so it is necessary to investigate dynamic responses of earth-rock dams under combined action of earthquake and wave. Considering material nonlinearity, seepage, wave action, fluid-solid interaction, liquid sloshing, a numerical calculation model is established, and Arbitrary Lagrange Eulerian method is used to solve the nonlinear dynamic coupling problem. Dynamic responses under wave, earthquake and wave+earthquake are studied comparatively, and influences of near and far field earthquakes and PGA on dynamic responses are investigated. Results show that values and distributions of dynamic responses under wave and earthquake are quite different, and dynamic responses were further increased considering combination of earthquake and wave. Dynamic responses under far field long period earthquake is significantly larger than that under near field earthquake. With the increase of PGA, increase trends of horizontal displacement, vertical displacement and plastic strain are increased, while increase trend of maximum shear stress is slowed down. It can be obtained that when earthquake intensity is large, earth-rock dam will be easily damaged due to excessive deformation
Advances in Terrestrial Mammal Movement Ecology: An Overview
As a research field which is blooming quickly in recent years, movement ecology has been a worldwide concern and interest. However, movement ecology is so comprehensive and complicated that many articles only focus on few aspects or species. As tracking technologies and methods of movement data analysis develop, the abundance of movement data becomes available for demonstrating more scientific facts about animal movement. This article is aimed to summarize the advances of terrestrial mammal movement ecology in the past years to show its critical and potential research fields, as well as trying to ascertain direction of these advances
A hybrid Particle Swarm Evolutionary Algorithm for Constrained Multi-Objective Optimization
In this paper, a hybrid particle swarm evolutionary algorithm is proposed for solving constrained multi-objective optimization. Firstly, in order to keep some particles with smaller constraint violations, a threshold value is designed, the updating strategy of particles is revised based on the threshold value; then in order to keep some particles with smaller rank values, an infeasible elitist preservation strategy is proposed in order to make the infeasible elitists act as bridges connecting disconnected feasible regions. Secondly, in order to find a set of diverse and well-distributed Pareto-optimal solutions, a new crowding distance function is designed for bi-objective optimization problems. It can assign larger crowding distance function values not only for the particles located in the sparse region but also for the particles located near to the boundary of the Pareto front. In this step, the reference points are given, and the particles which are near to the reference points are kept no matter how crowded these points are. Thirdly, a new mutation operator with two phases is proposed. In the first phase, the total force is computed first, then it is used as a mutation direction, searching along this direction, better particles will be found. The comparative study shows the proposed algorithm can generate widely spread and uniformly distributed solutions on the entire Pareto front
Seismic performance analysis of steel beam to CFST column connection with ductility and energy dissipation components
Concrete-filled steel tubular (CFST) column to steel beam joint with the ductility and energy dissipation components is a type of connection which is used in prefabricated structures, to improve the capacity of connections and construction efficiency. In this paper, two different type of steel beam to CFST column connections with the penetrated high-strength bolts and end-plate are investigated, i.e., steel beam to CFST column connection with end plate (CJ-1), and T-stub bolted (CJ-2) connections. The finite element model (FEM) of steel beam to CFST column connection with the penetrated high-strength bolts under cyclic loading are conducted based on the whole process of the nonlinear explicit analysis method using ABAQUS. The feasibility of FEM is verified by a set of experimental results performed by our research group, as well as available test results from other researchers. The failure modes, bearing capacity, energy dissipation capacity and ductility and rigidity degeneration were studied. As a result, the load-displacement hysteretic loop curve of CJ-2 connection is plump. However, the hysteresis curve of CJ-1 shows pinching phenomenon. The value of buckling load and ultimate load of CJ-2 increased by 28Â % and 30Â % respectively, compared with CJ-1. With respect of stress analysis, the plastic strain accumulation position distribution is relatively uniform duo to the T-stub connection, avoiding the penetrated high-strength bolt early yield or fracture. The results show that the steel beam to CFST column connection with penetrated bolts and T-stub connection has good seismic capacity
Diffraction limit of light in curved space
Overcoming diffraction limit is crucial for obtaining high-resolution image
and observing fine microstructure. With this conventional difficulty still
puzzling us and the prosperous development of wave dynamics of light
interacting with gravitational fields in recent years, how spatial curvature
affect the diffraction limit is an attractive and important question. Here we
investigate the issue of diffraction limit and optical resolution on
two-dimensional curved spaces - surfaces of revolution (SORs) with constant or
variable spatial curvature. We show that the diffraction limit decreases and
resolution is improved on SORs with positive Gaussian curvature, opening a new
avenue to super-resolution. The diffraction limit is also influenced by
propagation direction, as well as the propagation distance in curved space with
variable spatial curvature. These results provide a possible method to control
optical resolution in curved space or equivalent waveguides with varying
refractive index distribution and may allow one to detect the presence of
non-uniform strong gravitational effect by probing locally the optical
resolution
DialogPaint: A Dialog-based Image Editing Model
We introduce DialogPaint, a novel framework that bridges conversational
interactions with image editing, enabling users to modify images through
natural dialogue. By integrating a dialogue model with the Stable Diffusion
image transformation technique, DialogPaint offers a more intuitive and
interactive approach to image modifications. Our method stands out by
effectively interpreting and executing both explicit and ambiguous
instructions, handling tasks such as object replacement, style transfer, and
color modification. Notably, DialogPaint supports iterative, multi-round
editing, allowing users to refine image edits over successive interactions.
Comprehensive evaluations highlight the robustness and versatility of our
approach, marking a significant advancement in dialogue-driven image editing.Comment: 10 pages, 8 figure
Possible Bias in Supervised Deep Learning Algorithms for CT Lung Nodule Detection and Classification
Artificial Intelligence (AI) algorithms for automatic lung nodule detection and classification can assist radiologists in their daily routine of chest CT evaluation. Even though many AI algorithms for these tasks have already been developed, their implementation in the clinical workflow is still largely lacking. Apart from the significant number of false-positive findings, one of the reasons for that is the bias that these algorithms may contain. In this review, different types of biases that may exist in chest CT AI nodule detection and classification algorithms are listed and discussed. Examples from the literature in which each type of bias occurs are presented, along with ways to mitigate these biases. Different types of biases can occur in chest CT AI algorithms for lung nodule detection and classification. Mitigation of them can be very difficult, if not impossible to achieve completely
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