Mirror Model Research Articles

Do you see what I see? An investigation of the aesthetic experience in the laboratory and museum.

Two studies examined people’s aesthetic experiences of art in the laboratory and the museum. The theoretical framework guiding the research was based on the Mirror Model of Art (Tinio, 2013), which proposes that the process of artistic creation and artistic reception mirror each other. Study 1 used a think-aloud protocol to assess people’s natural and spontaneous reactions while looking at art. Study 2 examined whether presenting information about an artwork in a certain order (lower-order to higher-order information or higher-order to lower-order information) enhances aspects of the aesthetic experience and retention of information about art. Studies 1 and 2 were each conducted both in a laboratory and in a museum. The results replicate those of previous research that showed that the aesthetic experience of art is enhanced in the museum as compared with the laboratory setting. In addition, the results show that the effects of presenting information in a certain order (lower-order to higher-order information) depend on the context of presentation: museum visitors were better able to remember information about art than laboratory participants. Overall, the findings suggest that the Mirror Model is a good representation of how people naturally process art, but that certain aspects of the model could be optimized.

Fracture restoration technique based on 3D printing used in distal tibiofibular fractures

Objective To explore a 3D printing model of fracture restoration which can be used in preoperative planning and design for distal tibiofibular fractures. Methods A retrospective analysis was performed of the 35 patients with distal tibiofibular fracture who had been treated from October 2015 to September 2016 at our department. Bilateral tibiofibular CT scan was performed in all the cases to obtain Dicom data. Using Mimics 15.0 software, cross sections were created at 5 cm, 10 cm and 15 cm above the knee joint at the bilateral upper tibiae and marked as PT5, PT10 and PT15. The long and short axles on the left and right sides were measured and compared (LL vs. RL; LS vs. RS). After the STL files for 3D models were generated using Mimics 15.0 software, a real-sized 3D model of the distal tibiofibular fracture and a mirror model of the contralateral tibiofibula were printed. The fracture lines were drawn and preoperative manoeuvre was performed on the mirror 3D printed model. The real operation used the implants preoperatively designed; the actual screw lengths were measured and compared radiographically with those designed in the preoperative manoeuvre. Results All the data were collected of the long and short axles on the 3 cross-sections (PT5, PT10 and PT15) of the left and right sides of the proximal tibia. The samples were paired into 6 groups. The correlation coefficients of paired samples were greater than 0.95, showing an ex-tremely strong correlation. The differences between the left and right sides showed no statistically significance in paired samples of LR-RL and LS-RS groups on PT5, PT10 and PT15 cross-sections (P >0.05). All the 35 cases received surgical operation. The postoperative X-ray review showed fine agreement between actual surgery and preoperative design in terms of screw length and accuracy. The deviations were in an allowable range, leading to satisfactory internal fixation. Conclusions A mirror 3D model of the healthy side is of clinical value to some extent because it can serve as one for an anatomically reduced fracture which can be used for preoperative manoeuvre and preparation of implants. The contrasts between the long and short axles on the 3 cross-sections may simplify and facilitate comparisons of bilateral similarity, avoid the blindness in direct application of the health side mirror model for preoperative planning. Key words: Ankle joint; Fractures fixation, internal; 3D printing technology

Modeling and Iterative Learning Control of a Circular Deformable Mirror

An unconditionally stable finite difference scheme for systems whose dynamics are described by a fourth-order partial differential equation is developed using a regular hexagonal grid. The scheme is motivated by the well-known Crank-Nicolson discretization that was originally developed for second-order systems and it is used in this paper to develop a discrete in time and space model of a deformable mirror as a basis for control law design. As one example, the resulting model is used for iterative learning control law design and supporting numerical simulations are given.

Producing High Intense Attosecond Pulse Train by Interaction of Three-Color Pulse and Overdense Plasma

Amplifying the attosecond pulse by the chirp pulse amplification method is impossible. Furthermore, the intensity of attosecond pulse is low in the interaction of laser pulse and underdense plasma. This motivates us to propose using a multi-color pulse to produce the high intense attosecond pulse. In the present study, the relativistic interaction of a three-color linearly-polarized laser-pulse with highly overdense plasma is studied. We show that the combination of , and frequencies decreases the instance full width at half maximum reflected attosecond pulse train from the overdense plasma surface. Moreover, we show that the three-color pulse increases the intensity of generated harmonics, which is explained by the relativistic oscillating mirror model. The obtained results demonstrate that if the three-color laser pulse interacts with overdense plasma, it will enhance two orders of magnitude of intensity of ultra short attosecond pulses in comparison with monochromatic pulse.

Flatness-based open-loop and closed-loop control for electrostatic quasi-static microscanners using jerk-limited trajectory design

This paper describes the open-loop and closed-loop control for quasi-static microscanners exploiting the inherent flatness property. The developed nonlinear control method is verified on a gimbaled quasi-static/resonant scanning micro mirror with electrostatic staggered vertical comb (SVC) drive actuation. Based on a mechatronic micro mirror model, we present a flatness-based feed forward control method using jerk-limited trajectories to reduce undesired oscillations. For the closed-loop control we introduce a stabilizing linearizing feedback including an extended Luenberger observer for improvement of the command tracking in presence of model inaccuracies. The experimental results for both scenarios, open-loop and closed-loop control, are compared with simulations and further assessed in terms of performance and feasibility for industrial application.

Magnetic Fluid Deformable Mirror with a Two-Layer Layout of Actuators †

In this paper, a new type of magnetic fluid deformable mirror (MFDM) with a two-layer layout of actuators is proposed to improve the correction performance for full-order aberrations with a high spatial resolution. The shape of the magnetic fluid surface is controlled by the combined magnetic field generated by the Maxwell coil and the two-layer array of miniature coils. The upper-layer actuators which have a small size and high density are used to compensate for small-amplitude high-order aberrations and the lower-layer actuators which have a big size and low density are used to correct large-amplitude low-order aberrations. The analytical model of this deformable mirror is established and the aberration correction performance is verified by the experimental results. As a new kind of wavefront corrector, the MFDM has major advantages such as large stroke, low cost, and easy scalability and fabrication.

Search for electroweak-scale right-handed neutrinos and mirror charged leptons through like-sign dilepton signals

The existence of tiny neutrino masses at a scale more than a million times smaller than the lightest charged fermion mass, namely the electron, and their mixings can not be explained within the framework of the exceptionally successful Standard Model. There are four ideas that has been proposed to explain the tiny neutrino masses. These include the see-saw mechanism with a right handed neutrino at the GUT scale, and this is the most elegant mechanism. The other mechanisms are radiatively generated neutrino masses, the neutrino mass arising from a 2nd Higgs doublet having a tiny VEV and coupling only to the neutrinos, and finally the mirror model or simply the EW-scale $\nu_R$ model. The mirror model has new quarks and leptons of opposite chirality at the electroweak scale (for the same Standard Model gauge symmetry $SU(2)_W \times U(1)_Y$) compared to what we have for the Standard Model. With suitable modification of the Higgs sector, the EW-scale $\nu_R$ model satisfies the electroweak precision test and also the constraints coming from the observed 125-GeV Higgs scalar. Since in this model, the mirror fermions are required to be in the EW scale, these can be produced at the LHC giving final states with a very low background from the SM. One such final state is the same sign dileptons with large missing $p_T$ for the events. In this work, we explore the constraint provided by the $8$ TeV data, and prospect of observing this signal in the $13$ TeV runs at the LHC. Additional signals will be the presence of displaced vertices depending on the smallness of the Yukawa couplings of the mirror leptons with the ordinary leptons and the singlet Higgs present in the model. Of particular importance to the EW-scale $\nu_R$ model is the production of $\nu_R$ which will be a direct test of the seesaw mechanism at collider energies.

OSTEOPLASTY OF THE MAXILLA IN PATIENTS WITH UNILATERAL CLEFT LIP AND PALATE BY A MANDIBULAR BONE GRAFT WITH THE USE OF 3D COMPUTER MODELING

Rationale: Maxillary defects in patients with unilateral cleft lip and palate are very heterogeneous. The existing methods to assess the results of osteoplasty are suboptimal. The ways to measure the volume of a defect are not truly three-dimensional; instead, they are based on the sum of the sizes of maxillary defect measured in the sections done across the alveolar process. This is a more or less precise approximation and its calculation may be time-consuming. Aim: To evaluate efficacy of osteoplasty with a mandible bone autograft in children with cleft lip and palate and to determine the optimal pre-requisites for satisfactory treatment results. Materials and methods: We examined and treated 30 patients with unilateral cleft lip and palate and maxillary defects, aged from 7 to 17 (mean age 11.2 ± 3.5 years). The following types of abnormalities were found: incomplete cleft lip, alveolar process and palate; complete cleft lip, alveolar process and palate; complete cleft lip, alveolar process and palate with partial ossification of the posterior hard palate related to previous surgeries. In all patients, the surgical intervention consisted of maxillary osteoplasty with a combination graft consisting of the cortical plate from the mandible body, shaped to the existing defect, an autologous bone chips taken from the mandible ramus, and a Bio-Oss xenograft. The patients were divided into 4 groups, depending on their age, diagnosis, defect size, and postoperative complications. Three-dimensional modeling to determine the volume of the defect was performed as follows: a geometrical model of the mandible defect was obtained based on the mirror copy of the contralateral healthy part; the volume of the defect was computed as the difference between the baseline and the mirror model. The results of the osteoplasty were assessed by Bergland and Chelsea scales, as well as by our own scales. Results: The defect volumes were in the range of 0.46 to 2.9 cm3 (mean, 1.32 ± 0.54 cm3). According to Bergland and Chelsea scales, good results of osteoplasty were obtained in 83% (25 / 30) of the cases. The regenerated bone thickness was good in 94% (28 / 30) of the patients. The edge of the foramen piriformis was well shaped in 90% (27 / 30) of them. After surgery, the volumes of the defects in the patients with incomplete cleft lip, palate and alveolar process were significantly smaller than those in the patients with complete cleft and partial ossification of the posterior hard palate (on average, by 0.8 cm3, p = 0.0071). In all cases, where cortical mandible grafts were taken, it was possible to obtain cortical blocks of the needed size, starting from the age of 7, without any risk of damage to the immature permanent teeth. Graft formation from the mandible body was not associated with any local complications in any patient. Conclusion: Our method of 3D modeling to determine the volume of mandible defects is a truly 3D approach, which allows for a highly accurate quantitative assessment of the defects. The use of the combination grafts from the mandible body and the Bio-Oss xenografts for osteoplasty helps to replace the maxillary defect irrespective of the patient's age and the defect volume. Cortical grafts can be taken from the mandible starting from the age of 7 without any risk of damage to the immature permanent teeth. Irrespective of the clinical situation, the osteoplasty results are influenced predominantly by adherence to the surgical technique and to post-operative recommendations.

Polarization-preserving anisotropic mirror on the basis of metal–dielectric nanocomposite

The model of a polarization-preserving anisotropic mirror is proposed. The mirror is a plane boundary of a metal–dielectric nanocomposite that consists of silver spheroidal nanoparticles dispersed in a transparent matrix. The dependence of reflection spectra on the shape of the nanoparticles is studied. It is shown that in one region of the spectrum, the mirror preserves the sign of polarization in the reflected light.

Experimental study on ceiling temperature profile of sidewall fires at reduced pressure in an aircraft cargo compartment

Knowledge about the coupling effects of reduced pressure and sidewall restriction on ceiling temperature profile is crucial for the fire detection system of an aircraft cargo compartment. N-heptane fire tests at three places (floor center, flush with one sidewall, compartment corner) were conducted in a full scale simulated aircraft cargo compartment at 100kPa, 90kPa, 80kPa and 70kPa, since the pressure within an actual aircraft cargo compartment ranges from 100kPa at the sea level to 70kPa at the cruising altitude. Results show that due to the sidewall restriction and reduced pressure, less air entrainment into the flame results in higher maximum ceiling temperature. While ceiling temperature decay profile attenuates faster at reduced pressure and is little affected by sidewall restriction. A uniform correlation of maximum ceiling temperature considering reduced pressure and sidewall restriction is obtained by the introduction of air entrainment ratio Cα and modified mirror model coefficient. The classical correlations of Alpert, Heskestad and Delichatsios for the ceiling temperature decay profile are modified similarly to be extended to sidewall fires at reduced pressure and compared with results showing more accurate predicted results by Heskestad and Delichatsios’ method.

Modeling and experiment of surface error for large-aperture aspheric SiC mirror based on residual height and wheel wear

In the grinding process of large-aperture aspheric silicon carbide mirror, the wear of grinding wheel affects the surface accuracy seriously due to high hardness of silicon carbide and large diameter of aspheric mirror. Therefore, establishing surface error model of large-aperture aspheric silicon carbide mirror taking the wear of grinding wheel into account is of great significance to improve the processing quality and the imaging quality of aspheric mirror. The spiral grinding method is chosen to grind large-aperture aspheric SiC mirror in this work. The surface error of large-aperture aspheric silicon carbide mirror is established based on residual height and radial wear of grinding wheel using the grinding ratio as a bridge. The influence of grinding parameters on surface error is analyzed based on theoretical model. The results show that surface error increases with the increase of the rotation radius of workpiece and feed velocity of wheel, while it decreases with the increase of rotation velocity of workpiece and arc radius of wheel. The influence of the rotation velocity of workpiece and feed velocity of wheel is greater than that of the rotation radius of workpiece and arc radius of wheel. The regression equation of grinding ratio is established through grinding experiment, and the correlation coefficient is 0.9774 which verifies the reliability of the regression equation. Furthermore, the complete formula of surface error is acquired based on regression equation of grinding ratio. Finally, the grinding experiment of large-aperture aspheric silicon carbide mirror is carried out on the five-axis NC milling and grinding machine tool of HZ-091 type, and the error between measured value of grinding experiment and prediction value of theoretical model is less than 20%, which indicates that the theoretical model is reliable.

Experimental investigation of an aeroacoustic feedback mechanism on a two-dimensional side mirror model

The tonal self-noise emission of a two-dimensional blunt-body side mirror model is investigated experimentally in order to characterize the underlying source mechanism. The two-dimensional side mirror design is closely related to an automotive side mirror model11Early development state of an AUDI A7 side mirror. which generates tonal self-noise. The examined flow field and tonal noise emission of the two-dimensional side mirror indicates the existence of an aeroacoustic feedback mechanism comprising convective boundary layer instability waves, their scattering to acoustic waves at the trailing edge and the acoustic receptivity at a dominant feedback point. Fundamental evidence of this concept is found in the typical variation of the discrete-frequency noise emission with the free-stream velocity as well as a laminar flow separation in the vicinity of the trailing edge featuring massively amplified discrete-frequency modes. The existence of an aeroacoustic feedback loop is finally confirmed by the systematic variation of the feedback loop resonance length, which is a crucial loop parameter.

Rebound Vibration of Two-Plates Bonded Model for an Internal Mirror of SLR Camera

In this study, the rebound vibration characteristics of the internal mirror of an SLR camera are investigated using experimental models. The mechanism of the mirror rebound phenomena is tested by using the two-rectangular-metal-plates model, which has two plates bonded by double-sided tape. The mirror (plates) model is supported by fixing its longitudinal edge on a horizontal rotatable shaft. The bonded-mirror-model swings down freely around a horizontal axis and hits a stopper. A laser displacement meter is used to measures the amount of rebound and the mirror model vibration behavior. The rebound angle varies by the stopper position and the bonded position of the double-sided tape. In the case of a small rebound angle, the mirror part of the plate (upper side plate) vibrates with large amplitude, and its movement is measured by a 3-dimentional high-speed camera.

Cosmological and Particle Physics Constraints on a New Non-Abelian SU(3) Gauge Model for Ordinary/Dark Matter Interaction

We propose a mirror model for ordinary and dark matter that assumes a new SU(3) gauge group of transformations, as a natural extension of the Standard Model (SM). A close study of big bang nucleosynthesis, baryon asymmetries, cosmic microwave background bounds, galaxy dynamics, together with the Standard Model assumptions, help us to set a limit on the mass and width of the new gauge boson. The cross section for the elastic scattering of a dark proton by an ordinary proton is estimated and compare to the WIMP--nucleon experimental upper bounds. It is observed that all experimental bounds for the various cross sections can be accommodated consistently within the gauge model. We also suggest a way for direct detection of the new gauge boson via one example of a SM forbidden process: $e^+ + p \rightarrow \mu^+ + X$, where $X = \Lambda$ or $\Lambda_c$.

Bright high-order harmonic generation with controllable polarization from a relativistic plasma mirror.

Ultrafast extreme ultraviolet (XUV) sources with a controllable polarization state are powerful tools for investigating the structural and electronic as well as the magnetic properties of materials. However, such light sources are still limited to only a few free-electron laser facilities and, very recently, to high-order harmonic generation from noble gases. Here we propose and numerically demonstrate a laser–plasma scheme to generate bright XUV pulses with fully controlled polarization. In this scheme, an elliptically polarized laser pulse is obliquely incident on a plasma surface, and the reflected radiation contains pulse trains and isolated circularly or highly elliptically polarized attosecond XUV pulses. The harmonic polarization state is fully controlled by the laser–plasma parameters. The mechanism can be explained within the relativistically oscillating mirror model. This scheme opens a practical and promising route to generate bright attosecond XUV pulses with desirable ellipticities in a straightforward and efficient way for a number of applications.

The Range of a Rotor Walk

In rotor walk on a graph, the exits from each vertex follow a prescribed periodic sequence. We show that any rotor walk on the d-dimensional lattice ℤd visits at least on the order of td/(d+1) distinct sites in t steps. This result extends to Eulerian graphs with a volume growth condition. In a uniform rotor walk, the first exit from each vertex is to a neighbor chosen uniformly at random. We prove a shape theorem for the uniform rotor walk on the comb graph, showing that the size of the range is of order t2/3 and the asymptotic shape of the range is a diamond. Using a connection to the mirror model, we show that the uniform rotor walk is recurrent on two different directed graphs obtained by orienting the edges of the square grid: the Manhattan lattice and the F-lattice. We end with a short discussion of the time it takes for rotor walk to cover a finite Eulerian graph.

Sensitivity dependence of fiber loop mirror on the length of high birefringence fiber

A model of fiber loop mirror with the distinct concepts of sensing length and total length is established. The sensitivity dependence of fiber loop mirror on the sensing length and total length is discussed theoretically and experimentally. The sensor sensitivity showed being linearly dependent of the ratio of the sensing length and the total length. The experimental results well support the predications by the model.

Compliant deformable mirror approach for wavefront improvement

We describe a compliant static deformable mirror approach to reduce the wavefront concavity at the Navy Precision Optical Interferometer (NPOI). A single actuator pressing on the back surface of just one of the relay mirrors deforms the front surface in a correcting convex shape. Our design uses the mechanical advantage gained from a force actuator sandwiched between a rear flexure plate and the back surface of the mirror. We superimpose wavefront contour measurements with our finite element deformed mirror model. An example analysis showed improvement from 210-nm concave–concave wavefront to 51-nm concave–concave wavefront. With our present model, a 100-nm actuator increment displaces the mirror surface by 1.1 nm. We describe the need for wavefront improvement that arises from the NPOI reconfigurable array, offer a practical design approach, and analyze the support structure and compliant deformable mirror using the finite element method. We conclude that a 20.3-cm-diameter, 1.9-cm-thick Zerodur ® mirror shows that it is possible to deform the reflective surface and cancel out three-fourths of the wavefront deformation without overstressing the material.

Applying PyRosetta molecular energies to separate properly oriented protein models from mirror models, obtained from contact maps.

Reconstructing protein structure based on contact maps leads to two types of models: properly oriented models and mirror models. This is due to the fact that contact maps do not include information on protein chirality. Therefore, both types of model orientations share the same contact map and are geometrically allowed. In this work, we verified the hypothesis that some of the energy terms calculated by PyRosetta could be useful to distinguish between properly oriented and mirror models. We studied 440 models of all-alpha protein domains reconstructed manually from their contact maps, where 50 % of the models were properly oriented and 50 % had mirror orientation. We showed that dihedral angles and energy terms, based on the probability of specific geometrical arrangement of the residues, differed significantly for properly oriented and mirror models.Electronic supplementary materialThe online version of this article (doi:10.1007/s00894-016-2975-3) contains supplementary material, which is available to authorized users.

Exploring information from the topology beneath the Gene Ontology terms to improve semantic similarity measures

Measuring the similarity between pairs of biological entities is important in molecular biology. The introduction of Gene Ontology (GO) provides us with a promising approach to quantifying the semantic similarity between two genes or gene products. This kind of similarity measure is closely associated with the GO terms annotated to biological entities under consideration and the structure of the GO graph. However, previous works in this field mainly focused on the upper part of the graph, and seldom concerned about the lower part. In this study, we aim to explore information from the lower part of the GO graph for better semantic similarity. We proposed a framework to quantify the similarity measure beneath a term pair, which takes into account both the information two ancestral terms share and the probability that they co-occur with their common descendants. The effectiveness of our approach was evaluated against seven typical measurements on public platform CESSM, protein–protein interaction and gene expression datasets. Experimental results consistently show that the similarity derived from the lower part contributes to better semantic similarity measure. The promising features of our approach are the following: (1) it provides a mirror model to characterize the information two ancestral terms share with respect to their common descendant; (2) it quantifies the probability that two terms co-occur with their common descendant in an efficient way; and (3) our framework can effectively capture the similarity measure beneath two terms, which can serve as an add-on to improve traditional semantic similarity measure between two GO terms. The algorithm was implemented in Matlab and is freely available from http://ejl.org.cn/bio/GOBeneath/.