225 research outputs found
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Reflective and relativistic refactoring with feature-awareness
Refactoring is a core technology in modern software development. It is central to popular software design movements, such as Extreme Programming [23] and Agile software development [91], and all major Integrated Development Environments (IDEs) today offer some form of refactoring support. Despite this, refactoring engines have languished behind research. Modern IDEs offer no means to sequence refactorings to automate program changes. Further, current refactoring engines exhibit problems of speed and expressivity, which makes writing composite refactorings such as design patterns infeasible. Even worse, existing refactoring tools for Object-Oriented languages are unaware of configurations in Software Product Lines (SPLs) codebases. With this motivation in mind, this dissertation makes three contributions to address these issues: First, we present the Java API library, called R2, to script Eclipse refactorings to retrofit design patterns into existing programs. We encoded 18 out of 23 design patterns described by Gang-of-Four [57] as R2 scripts and explain why the remaining refactorings are inappropriate for refactoring engines. R2 sheds light on why refactoring speed and expressiveness are critical issues for scripting. Second, we present a new Java refactoring engine, called R3, that addresses an Achilles heel in contemporary refactoring technology, namely scripting performance. Unlike classical refactoring techniques that modify Abstract Syntax Trees (ASTs), R3 refactors programs by rendering ASTs via pretty printing. AST rendering never changes the AST; it only displays different views of the AST/program. Coupled with new ways to evaluate refactoring preconditions, R3 increases refactoring speed by an order of magnitude over Eclipse and facilitates computing views of a program where the original behavior is preserved. Third, we provide a feature-aware refactoring tool, called X15, for SPL codebases written in Java. X15 takes advantage of R3's view rendering to implement a projection technology in Feature-Oriented Software Development, which produces subprograms of the original SPL by hiding unneeded feature code. X15 is the first feature-aware refactoring tool for Java that implements a theory of refactoring feature modules, and allows users to edit and refactor SPL programs via “views”. In the most demanding experiments, X15 barely runs a second slower than R3, giving evidence that refactoring engines for SPL codebases can indeed be efficient.Computer Science
M-theory on pp-waves with a holomorphic superpotential and its membrane and matrix descriptions
We study a new class of inhomogeneous pp-wave solutions with 8 unbroken
supersymmetries in D=11 supergravity. The 9 dimensional transverse space is
Euclidean and split into 3 and 6 dimensional subspaces. The solutions have
non-constant gauge flux, which are described in terms of an arbitrary
holomorphic function of the complexified 6 dimensional space. The supermembrane
and matrix theory descriptions are also provided and we identify the relevant
supersymmetry transformation rules. The action also arises through a
dimensional reduction of N=1, D=4 supersymmetric Yang-Mills theory coupled to 3
gauge adjoint and chiral multiplets, whose interactions are determined by the
holomorphic function of the supergravity solution now constituting the
superpotential.Comment: 19 pages;v2 21p, added discussion and ref
Classification of the BPS states in Bagger-Lambert Theory
We classify, in a group theoretical manner, the BPS configurations in the
multiple M2-brane theory recently proposed by Bagger and Lambert. We present
three types of BPS equations preserving various fractions of supersymmetries:
in the first type we have constant fields and the interactions are purely
algebraic in nature; in the second type the equations are invariant under
spatial rotation SO(2), and the fields can be time-dependent; in the third
class the equations are invariant under boost SO(1,1) and provide the
eleven-dimensional generalizations of the Nahm equations. The BPS equations for
different number of supersymmetries exhibit the division algebra structures:
octonion, quarternion or complex.Comment: 28+1 pages, No figure; v2 Sec.3.3 slightly expanded, typos fixed; v3
some comments added, to appear in JHE
PP-GAN : Style Transfer from Korean Portraits to ID Photos Using Landmark Extractor with GAN
The objective of a style transfer is to maintain the content of an image
while transferring the style of another image. However, conventional research
on style transfer has a significant limitation in preserving facial landmarks,
such as the eyes, nose, and mouth, which are crucial for maintaining the
identity of the image. In Korean portraits, the majority of individuals wear
"Gat", a type of headdress exclusively worn by men. Owing to its distinct
characteristics from the hair in ID photos, transferring the "Gat" is
challenging. To address this issue, this study proposes a deep learning network
that can perform style transfer, including the "Gat", while preserving the
identity of the face. Unlike existing style transfer approaches, the proposed
method aims to preserve texture, costume, and the "Gat" on the style image. The
Generative Adversarial Network forms the backbone of the proposed network. The
color, texture, and intensity were extracted differently based on the
characteristics of each block and layer of the pre-trained VGG-16, and only the
necessary elements during training were preserved using a facial landmark mask.
The head area was presented using the eyebrow area to transfer the "Gat".
Furthermore, the identity of the face was retained, and style correlation was
considered based on the Gram matrix. The proposed approach demonstrated
superior transfer and preservation performance compared to previous studies
Design and Implementation of a Wireless Charging-Based Cardiac Monitoring System Focused on Temperature Reduction and Robust Power Transfer Efficiency
Wireless power transfer systems are increasingly used as a means of charging implantable medical devices. However, the heat or thermal radiation from the wireless power transfer system can be harmful to biological tissue. In this research, we designed and implemented a wireless power transfer system-based implantable medical device with low thermal radiation, achieving 44.5% coil-to-coil efficiency. To suppress thermal radiation from the transmitting coil during charging, we minimized the ESR value of the transmitting coil. To increase power transfer efficiency, a ferrite film was applied on the receiving part. Based on analyses, we fabricated a cardiac monitoring system with dimensions of 17 x 24 x 8 mm(3) and implanted it in a rat. We confirmed that the temperature of the wireless charging device increased by only 2 degrees C during the 70 min charging, which makes it safe enough to use as an implantable medical device charging system.11Ysciescopu
Restoration of the JPEG Maximum Lossy Compressed Face Images with Hourglass Block based on Early Stopping Discriminator
When a JPEG image is compressed using the loss compression method with a high
compression rate, a blocking phenomenon can occur in the image, making it
necessary to restore the image to its original quality. In particular,
restoring compressed images that are unrecognizable presents an innovative
challenge. Therefore, this paper aims to address the restoration of JPEG images
that have suffered significant loss due to maximum compression using a
GAN-based net-work method. The generator in this network is based on the U-Net
architecture and features a newly presented hourglass structure that can
preserve the charac-teristics of deep layers. Additionally, the network
incorporates two loss functions, LF Loss and HF Loss, to generate natural and
high-performance images. HF Loss uses a pretrained VGG-16 network and is
configured using a specific layer that best represents features, which can
enhance performance for the high-frequency region. LF Loss, on the other hand,
is used to handle the low-frequency region. These two loss functions facilitate
the generation of images by the generator that can deceive the discriminator
while accurately generating both high and low-frequency regions. The results
show that the blocking phe-nomenon in lost compressed images was removed, and
recognizable identities were generated. This study represents a significant
improvement over previous research in terms of image restoration performance
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