Jiming Ma
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View article: Focal spot diagnostic of pulsed planar anticathode accelerator with compressed streak imaging
Focal spot diagnostic of pulsed planar anticathode accelerator with compressed streak imaging Open
The spatial-temporal distribution of the focal spot is a key characteristic for evaluating a pulsed accelerator. However, the small number of frames and the low frame frequency limit the accurate analysis of the focal spot evolution proces…
View article: Complex Hyperbolic Geometry of Chain Links
Complex Hyperbolic Geometry of Chain Links Open
The complex hyperbolic triangle group $Γ=Δ_{4,\infty,\infty;\infty}$ acting on the complex hyperbolic plane ${\bf H}^2_{\mathbb C}$ is generated by complex reflections $I_1$, $I_2$, $I_3$ such that the product $I_2I_3$ has order four, the …
View article: Figure-eight knot is always over there
Figure-eight knot is always over there Open
It is well-known that complex hyperbolic triangle groups $Δ(3,3,4)$ generated by three complex reflections $I_1,I_2,I_3$ in $\mbox{PU(2,1)}$ has 1-dimensional moduli space. Deforming the representations from the classical $\mathbb{R}$-Fuch…
View article: The topology of the Eisenstein-Picard modular surface
The topology of the Eisenstein-Picard modular surface Open
The Eisenstein-Picard modular surface $M$ is the quotient space of the complex hyperbolic plane by the modular group $\rm PU(2,1; \mathbb{Z}[ω])$. We determine the global topology of $M$ as a 4-orbifold.
View article: Three-dimensional complex reflection groups via Ford domains
Three-dimensional complex reflection groups via Ford domains Open
We initiate the study of deformations of groups in three-dimensional complex hyperbolic geometry. Let $$G=\left\langle ι_1, ι_2, ι_3, ι_4 \Bigg| \begin{array}{c} ι_1^2= ι_2^2 = ι_3^2=ι_4^2=id,\\ (ι_1 ι_3)^{2}=(ι_1 ι_4)^{3}=(ι_2 ι_4)^{2}=id…
View article: The moduli space of the modular group in three-dimensional complex hyperbolic geometry
The moduli space of the modular group in three-dimensional complex hyperbolic geometry Open
We study the moduli space of discrete, faithful, type-preserving representations of the modular group $\mathbf{PSL}(2,\mathbb{Z})$ into $\mathbf{PU}(3,1)$. The entire moduli space $\mathcal{M}$ is a union of $\mathcal{M}(0,\frac{2π}{3},\fr…
View article: Geometrically bounding 3–manifolds, volumeand Betti numbers
Geometrically bounding 3–manifolds, volumeand Betti numbers Open
It is well known that an arbitrary closed orientable $3$-manifold can be realized as the unique boundary of a compact orientable $4$-manifold, that is, any closed orientable $3$-manifold is cobordant to zero. In this paper, we consider the…
View article: Menger curve and Spherical CR uniformization of a closed hyperbolic 3-orbifold
Menger curve and Spherical CR uniformization of a closed hyperbolic 3-orbifold Open
Let G6,3= ⟨a0, · · · , a5|a3i = id, aiai+1 = ai+1ai, i ∈ Z/6Z⟩ be a hyperbolic group with boundary the Menger curve. Granier [10] constructed a discrete, convex cocompact and faithful representation p of G6,3 into PU(2,1). We show the 3-or…
View article: Temperature dependence of luminescence characteristics of LYSO:Ce scintillator under x-ray excitation
Temperature dependence of luminescence characteristics of LYSO:Ce scintillator under x-ray excitation Open
Temperature dependence of the luminescence characteristics of Lu1.84Y0.16SiO5:Ce (LYSO:Ce) scintillator was investigated under x-ray excitation. The luminescence decay time, light yield, radioluminescence (RL) spectra, spatial resolution, …
View article: Single-shot imaging with multiple frames through delaying optical images
Single-shot imaging with multiple frames through delaying optical images Open
A single-shot imaging system with multiple frames has been developed, which can record sequential multiple frames by delaying multiple optical images with fiber bundles and then capturing the images with a single intensified camera. The ob…
View article: A Feature Selection Method of the Island Algorithm Based on Gaussian Mutation
A Feature Selection Method of the Island Algorithm Based on Gaussian Mutation Open
With the development of the Internet, the data we are dealing with is becoming more and more complex, which brings about various difficulties and problems when we process and use data. Feature selection methods are able to filter and remov…
View article: Spherical CR uniformization of the magic 3-manifold
Spherical CR uniformization of the magic 3-manifold Open
We show the 3-manifold at infinity of the complex hyperbolic triangle group $Δ_{3,\infty,\infty;\infty}$ is the three-cusped "magic" 3-manifold $6_1^3$. We also show the 3-manifold at infinity of the complex hyperbolic triangle group $Δ_{3…
View article: An Improved Island Algorithm and Its Application in Model Optimization of Micro Soft Robot
An Improved Island Algorithm and Its Application in Model Optimization of Micro Soft Robot Open
Aiming at the shortcomings of the original island algorithm (IA), which has a slow convergence speed and is prone to local optimality, the island algorithm with the characteristics of Levy flight (LevyIA) was proposed by introducing the Le…
View article: Orientable hyperbolic 4-manifolds over the 120-cell
Orientable hyperbolic 4-manifolds over the 120-cell Open
Since there is no hyperbolic Dehn filling theorem for higher dimensions, it is challenging to construct explicit hyperbolic manifolds of small volume in dimension at least four. Here, we build up closed hyperbolic 4-manifolds of volume by…
View article: Algebraic fibrations of certain hyperbolic 4-manifolds
Algebraic fibrations of certain hyperbolic 4-manifolds Open
Algebraically fibering group is an algebraic generalization of the fibered 3-manifold group in higher dimensions. Let $M(\mathcal{P})$ and $M(\mathcal{E})$ be the cusped and compact hyperbolic real moment-angled manifolds associated to the…
View article: The Teaching Reform of Compiling Principle Based on System Ability Training
The Teaching Reform of Compiling Principle Based on System Ability Training Open
In this paper, the computer class curriculum goal, content the present situation of computer teaching have been analyzed in computer related ability and the overall goals are set up on the basis of the current education teaching reform eff…
View article: Quasi-homomorphisms on mapping class groups vanishing on a handlebody group
Quasi-homomorphisms on mapping class groups vanishing on a handlebody group Open
We construct infinitely many linearly independent quasi-homomorphisms on the mapping class group of a Riemann surface with genus at least two which vanish on a handlebody subgroup. As a corollary, we disprove a conjecture of Reznikov on bo…
View article: Analytical calculation method of free static magnetic field point in magnetic signal measurement
Analytical calculation method of free static magnetic field point in magnetic signal measurement Open
In the application of magnetic signal measurement such as non-invasive temperature of ferromagnetic resonance, magnetic nanoparticle fluid hyperthermia, magnetic nanoparticle concentration imaging, etc., it is necessary to generate a free …
View article: Inverse Liner Z-Pinch: An Experimental Pulsed Power Platform for Studying Radiative Shocks
Inverse Liner Z-Pinch: An Experimental Pulsed Power Platform for Studying Radiative Shocks Open
We present a new experimental platform for studying radiative shocks using an ``inverse liner z-pinch'' configuration. This platform was tested on the MAGPIE pulsed power facility (~1 MA with a rise time of ~240 ns) at Imperial College Lon…
View article: Ion heating and magnetic flux pile-up in a magnetic reconnection experiment with super-Alfvénic plasma inflows
Ion heating and magnetic flux pile-up in a magnetic reconnection experiment with super-Alfvénic plasma inflows Open
This work presents a magnetic reconnection experiment in which the kinetic, magnetic, and thermal properties of the plasma each play an important role in the overall energy balance and structure of the generated reconnection layer. Magneti…
View article: Hyperbolic 4-manifolds over the 120-cell
Hyperbolic 4-manifolds over the 120-cell Open
Since there is no hyperbolic Dehn filling theorem in higher dimensions, it is difficult to construct concrete hyperbolic manifolds of small volume in dimension at least four. We build up a census of closed hyperbolic 4-manifolds of volume …
View article: Development of an all-optical framing camera and its application on the Z-pinch
Development of an all-optical framing camera and its application on the Z-pinch Open
An all-optical framing camera has been developed which measures the spatial profile of photons flux by utilizing a laser beam to probe the refractive index change in an indium phosphide semiconductor. This framing camera acquires two frame…
View article: A Method of Setting Magnetic Field Device Based on Magnetic Nano-tumor Thermotherapy
A Method of Setting Magnetic Field Device Based on Magnetic Nano-tumor Thermotherapy Open
In this paper, a new method to set up the static magnetic field of the targeted magnetic fluid hyperthermia is presented based on the study of magnetic nanoparticles and biological heat transfer mechanism. Magnetic field generating system …
View article: Geometrically bounding 3-manifolds with the same volume
Geometrically bounding 3-manifolds with the same volume Open
It is well known that an arbitrary closed orientable $3$-manifold can be realized as the unique boundary of a compact orientable $4$-manifold, that is, any closed orientable $3$-manifold is cobordant to zero. In this paper, we consider the…
View article: Geometrically bounding 3-manifold, volume and Betti number
Geometrically bounding 3-manifold, volume and Betti number Open
It is well known that an arbitrary closed orientable $3$-manifold can be realized as the unique boundary of a compact orientable $4$-manifold, that is, any closed orientable $3$-manifold is cobordant to zero. In this paper, we consider the…
View article: Anomalous Heating and Plasmoid Formation in a Driven Magnetic Reconnection Experiment
Anomalous Heating and Plasmoid Formation in a Driven Magnetic Reconnection Experiment Open
We present a detailed study of magnetic reconnection in a quasi-two-dimensional pulsed-power driven laboratory experiment. Oppositely directed magnetic fields (B=3 T), advected by supersonic, sub-Alfvénic carbon plasma flows (V_{in}=50 km/…