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A bstract Global cosmic strings are predicted in many motivated extensions to the Standard Model of particle physics, with close connections to axion dark matter physics. Recent studies suggest that, although subdominant relative to Goldstone emission, gravitational wave (GW) signals from global strings can be detectable with current and planned GW detectors such as LIGO, LISA, DECIGO/BBO, ET/CE and AEDGE/AION, as well as pulsar timing arrays such as PPTA, NANOGrav and SKA. This work is an extensive, updated study on GWs from a global cosmic string network, taking into account of the most recent developments related to the subject. The main analysis is based on the analytical Velocity-dependent One-Scale (VOS) model calibrated with recent simulation results, which provides a generic protocol for such calculations with details given. We also demonstrate how the GW signal can be influenced with variations to the baseline model: this includes considering the uncertainties of model parameters and the potential deviation from the conventional VOS model prediction (i.e. the scaling behavior) as suggested by some of the recent simulation results. Furthermore, we investigated in detail the effect of a non-standard cosmology (e.g. early matter domination or kination) or new particle species on the GW signals from global strings. We demonstrate that the frequency spectrum of GW background from global cosmic strings can be used to probe the cosmic history prior to the Big Bang nucleosynthesis (BBN) (i.e. the primordial dark age) up to a temperature of T ∼ 10 8 GeV.

A bstract We explore simple Higgs-portal models of dark matter (DM) with spin 1/2, 3/2, and 1, respectively, applying to them constraints from the LUX and PandaX-II direct detection experiments and from LHC measurements on the 125-GeV Higgs boson. With only one Higgs doublet, we find that the spin-1/2 DM having a purely scalar effective coupling to the doublet is viable only in a narrow range of mass near the Higgs pole, whereas the vector DM is still allowed if its mass is also close to the Higgs pole or exceeds 1.4 TeV, both in line with earlier analyses. Moreover, the spin-3/2 DM is in a roughly similar situation to the spin-1/2 DM, but has surviving parameter space which is even more restricted. We also consider the two-Higgs-doublet extension of each of the preceding models, assuming that the expanded Yukawa sector is that of the two-Higgs-doublet model of type II. We show that in these two-Higgs-doublet-portal models significant portions of the DM mass regions excluded in the simplest scenarios by direct search bounds can be reclaimed due to suppression of the effective DM interactions with nucleons at some ratios of the CP -even Higgs bosons’ couplings to the up and down quarks. The regained parameter space contains areas which can yield a DM-nucleon scattering cross-section that is far less than its current experimental limit or even goes below the neutrino-background floor.

A bstract In the SU(3) C × SU(2) L × SU(2) R × U(1) ( B − L )/2 extension of the standard model, a minimal (but asymmetric) scalar sector consists of one SU(2) R × U(1) ( B − L )/2 doublet and one SU(2) L × SU(2) R bidoublet. Previous and recent studies have shown that this choice is useful for understanding neutrino mass as well as dark matter. The constraints from flavor changing neutral currents mediated by the scalar sector are discussed in the context of the latest experimental data.

The Taiwan Photon Source (TPS) 32A Tender X-ray Absorption Spectroscopy Beamline, under the 3 rd phase of the beamline construction project at the National Synchrotron Radiation Research Center (NSRRC), has completed its hardware structure and began commissioning in September 2023. Multiple software tools have been developed to integrate the beamline components specifically for commissioning, including the slits scanning, energy scanning, energy calibration, saving/loading parameters, and spectral scanning software. These software tools integrate the functionalities of individual optical components and automate steps required for setting experimental conditions. A user-friendly graphical user interface (GUI) can speed up the commissioning process and lower the barrier for user operation. The workstation with completed software interfaces has been established for the concept development of beamline control logic and for general X-ray absorption spectroscopy users. Developing features such as the fly-scan function and in-situ measurements aim to facilitate user experiments and enhance the scanning capabilities of the TPS 32A beamline.

The TPS 31A PXM-TXM beamline, which utilizes the high flux wiggler source W100 at the TPS of NSRRC, has been constructed to support a broad range of scientific research through three projection X-ray microscopy (PXM) modes and one transmission X-ray microscopy (TXM) mode. The high-X-ray-energy capabilities of the PXM modes — white-light mode, double W-Si/Si multilayer monochromator mode and double Si(111) crystal monochromator mode — allow for penetration depths of several centimeters, with energies reaching up to 50 keV. The spatial resolution of PXM modes is as fine as 1 μm, enabling detailed observation of microstructures. TXM mode provides a spatial resolution of 50 nm, facilitating the exploration on nanometer-scale structures. The large fields of view — several millimetres for PXM and 24 μm for TXM — enhance non-destructive imaging capabilities. Additionally, the excellent temporal resolution enables successful in operando tomography using the PXM modes. Energy-resolved elemental mapping and quantitative analysis of tomography are also feasible.

Projection X-ray microscopy (PXM) and transmission X-ray microscopy (TXM) have been established at beamline 31 at the Taiwan Photon Source (TPS). The TPS 31A beamline is sourced by a wiggler with multiple beam modes: white beam, high-flux mono-beam, and high-resolution mono-beam modes. The PXM is based on a collimated beam, and the TXM is full-field microscopy based on a zoneplate. The PXM system and TXM share the same detector platform, which is equipped with different kinds of detector systems for PXM and TXM. The PXM was designed for high-speed 3D tomography with an automatic tray system for loading and unloading samples, including a robotic arm and pre-alignment system. Both the PXM and TXM systems were designed for use in situ, which requires longer working distance for the sample’s environmental cell.

Motion blur is a common problem in digital photography. In the dim light, a long exposure time is needed to acquire a satisfactory photograph, and if the camera shakes during exposure, a motion blur is captured. Image deblurring has become a crucial image-processing challenge, because of the increased popularity of handheld cameras. Traditional motion deblurring methods assume that the blur degradation is shift-invariant; therefore, the deblurring problem can be reduced to a deconvolution problem. Edge-specific motion deblurring sharpened the strong edges of the image and then used them to estimate the blur kernel. However, this also enhanced noise and narrow edges, which cause ambiguity and ringing artifacts. We propose a hybrid-based single image motion deblurring algorithm to solve these problems. First, we separated the blurred image into strong edge parts and smooth parts. We applied the improved patch-based sharpening method to enhance the strong edge for kernel estimation, but for the smooth part, we used the bilateral filter to remove the narrow edge and the noise for avoiding the generation of ringing artifacts. Experimental results show that the proposed method is efficient at deblurring for a variety of images and can produce images of a quality comparable to other state-of-the-art techniques.

Production technology has increased rapidly with the development of industrial technology. Conventional human visual inspection is insufficient for conducting quality control under this increased capacity. Therefore, high-speed and high-accuracy automated optical inspection is becoming increasingly crucial. In this article, we propose an automated inspection method for a compact camera lens using a circle Hough transformation, weighted Sobel filter, and polar transformation. Our analysis of defects in the compact camera lens identified problems including of the circular texture and the non-fixed position of the inspection region. To overcome these problems, we design an inspection algorithm for locating and inspecting a circular region. A machine learning support vector machine method is then applied for obtaining a precise detection result. The experimental results show that the proposed inspection method is suitable for detecting defects in a complicated circular inspection region, and that the proposed system exhibited high performance.

One of the most common artifacts in digital photography is motion blur. When capturing an image under dim light by using a handheld camera, the tendency of the photographer’s hand to shake causes the image to blur. In response to this problem, image deblurring has become an active topic in computational photography and image processing in recent years. From the view of signal processing, image deblurring can be reduced to a deconvolution problem if the kernel function of the motion blur is assumed to be shift invariant. However, the kernel function is not always shift invariant in real cases; for example, in-plane rotation of a camera or a moving object can blur different parts of an image according to different kernel functions. An image that is degraded by multiple blur kernels is called a nonuniform blur image. In this paper, we propose a novel single image deblurring algorithm for nonuniform motion blur images that is blurred by moving object. First, a proposed uniform defocus map method is presented for measurement of the amounts and directions of motion blur. These blurred regions are then used to estimate point spread functions simultaneously. Finally, a fast deconvolution algorithm is used to restore the nonuniform blur image. We expect that the proposed method can achieve satisfactory deblurring of a single nonuniform blur image.

In this talk we will explore the possibility of adding a local U(1) dark sector to the standard model with the Higgs boson as a portal connecting the visible standard model sector and the dark one. We will discuss existing experimental constraint on the model parameters from the invisible width of Higgs decay. Implications of such a dark U(1) sector on phenomenology at the Large Hardon Collider will be addressed. In particular, detailed results for the non-standard signals of multi-lepton-jets that arise from this simple dark sector will be presented.