A Prelude Staircase to a Type V Intermittency in Two—Dimensional Discontinuous Maps

A sequence of periodic attractors has been observed in a two-dimensional discontinuous map, which canbe considered as a model of impact oscillator. The so-called 'transfer number', which is defined as the mean numberof transfer from non-impact state to impact state per iteration, is locked onto a lot of rational values to form a curveconsisting of many steps. Our numerical investigation confirms that every step is confined by conditions created by thecollision between the periodic orbit and the discontinuous boundary of the system. After the last collision the systemshows a chaotic motion with intermittent characteristics. Therefore the staircase can be addressed as a 'prelude staircaseto type V intermittency'. The similar phenomenon has also been observed in a model of electric circuit. These resultsof our study suggest that this kind of staircases is common in two (or even higher) dimensional discontinuous maps.

Seismic performance analysis and design suggestion for frame buildings with cast-in-place staircases

Many staircases in reinforced concrete （RC） frame structures suffered severe damage during the Wenchuan earthquake. Elastic analyses for 18 RC structure models with and without staircases are conducted and compared to study the influence of the staircase on the stiffness, displacements and internal forces of the structures. To capture the yielding development and damage mechanism of frame structures, elasto-plastic analysis is carried out for one of the 18 models. Based on the features observed in the analyses, a new type of staircase design i.e., isolating them from the master structure to eliminate the effect of K-type struts, is proposed and discussed. It is concluded that the proposed method of staircase isolation is effective and feasible for engineering design, and does not significantly increase the construction cost.

Improving the Seismic Performance of Staircases in Building Structures with a Novel Isolator

A staircase provides the main escape way from a building in an emergency.Unfortunately,it may suffer severe damages or even collapse during an earthquake.For improving the seismic performance of staircases,this paper proposes an innovative staircase isolator with the features of lightweight,costeffective and ease of construction and replacement,which is formed by suitable engineering plastic shims between rubber layers.A connection construction scheme is also proposed for the isolated staircase.Systematic performance tests have been carried out to characterize the isolator in terms of mechanic behavior and ultimate states.The test results show that mechanical properties of the proposed staircase isolator are excellent and suitable for staircase in building structure.In order to investigate the influence of staircase on building structural responses,time history analyses of a typical building structure without staircase(WS),with fixed staircase(FS)and with isolated staircase(IS)are conducted and compared within the environment of SAP2000.Results show that staircase isolation can effectively eliminate the diagonal bracing effect of staircase slab and make structural components uniformly stressed.When the novel isolator is employed for staircase in a building structure,there is no vulnerable position in staircase and the performance of staircase in building structure can be greatly enhanced.

Nuclear-Magnetic-Resonance Properties of the Staircase Kagome Antiferromagnet PbCu3TeO7

We report the first nuclear magnetic resonance （NMR） study on single crystals of staircase Kagome antiferromagnet PbCu3Te07 （TN1 -36K）. A Curie constant θ -140K is obtained by a Curie Weiss fit to the high- temperature Knight shift of 125 Te. The hyperfine coupling constant is estimated to be 125Ahf = -67 kOe/#B, and a strong interlayer coupling among staircase Kagome planes is suggested with such a large hyperfine coupling, according to the lattice structure. The 63,65Cu NMR spectra are found by the zero-field （ZF） NMR at T = 2 K, and the internal hyperfine fields are estimated to be 10.3 T and 9.6 T, for Cu（1） and Cu（2） sites, respectively, in the lattice. A second type of ZF NMFt signal with a large rf enhancement is also seen after field-cycling through a high magnetic field.

Computerised Gate Firing Control for 17-Level MLI using Staircase PWM

A basic 7-level MLI topology is developed and the same is extended to the 9-level then further increased to 17-levels.The developed structure minimizes the component’s count and size to draw out the system economy.Despite the various advantages of MLIs,efficiency and reliability play a major role since the usage of components is higher for getting a low Total Harmonics Distortion(THD)value.This becomes a major challenge incorporated in boosting the efficiency without affecting the THD value.Various parametric observations are done and realized for the designed 9-level and 17-level MLI,being the Total Standing Voltage(TSV),efficiency,cost function per level count,and power loss.The respective parameters are compared with several existing and modern circuits and found to be effective in their performance.A novel single-phase 17-level asymmetrical Multi-Level Inverter(MLI)topology is developed to reduce the number of overall components.The developed topology generates 17-levels by using unequal DC sources.The developed MLI is proved under various tests con-ducted experimentally for the various loads like resistive,inductive,and combinational loads.A detailed comparison is done on several factors and represented graphically represented.Further,the proposed design provides a less TSV value is 6 V_(dc),efficiency is 94.21%and cost factor per level CF/L value for both values ofαis 2.01 and 2.05 and devices count with a low THD value 41.4%with respectively.

Non-linear Invertible Maps that Preserve Staircase Subalgebras

Let g be the general linear Lie algebra consisting of all n x n matrices over a field F and with the usual bracket operation {x, y} =xy - yx. An invertible map φ ： g →g is said to preserve staircase subalgebras if it maps every staircase subalgebra to some staircase subalgebra of the same dimension. In this paper, we devote to giving an explicit description on the invertible maps on g that preserve staircase subalgebras.

User Preference Survey on Staircase Rotation

Staircase is an important means of vertical transportation. Staircase design exerts a great influence on the aesthetics, transportation efficiency, user comfort and experience level. In this paper, a survey on the staircase rotation preference was conducted, based on the environment behavior studies. Different user frequencies of a pair of scissors stairs in the 2nd teaching building of North China University of Technology were analyzed. The psychological effect was evaluated and quantified, and the user preference on the two staircase rotations was then withdrawn. The survey found that the type of staircase with clockwise upstairs was much more preferred （78%） than the other staircase rotation anti-clock upstairs. Considering different genders, the female shows a 66% higher preference inclination of this type of staircase rotation than the male. To improve the transportation efficiency of the staircase in case of fire, the result of this paper can be very constructive for the evacuation staircase rotation choice for the high-rise buildings.

Adaptability of Conservative Staircase Scheme for Live Videos

Existing broadcasting schemes provide services for the stored videos. The basic approach in these schemes is to divide the video into segments and organize them over the channels for proper transmission. Some schemes use segments as a basic unit, whereas the others require segments to be further divided into subsegments. In a scheme, the number of segments/subsegments depends upon the bandwidth allocated to the video by the video server. For constructing segments, the video length should be known. If it is unknown, then the segments cannot be constructed and hence the scheme cannot be applied to provide the video services. This is an important issue especially in live broadcasting applications wherein the ending time of the video is unknown, for example, cricket match. In this paper, we propose a mechanism for the conservative staircase scheme so that it can support live video broadcasting.

Quantum Conductance Staircase of Edge Hole Channels in Silicon Quantum Wells

We present the findings for the quantum conductance staircase of holes that is caused by the edge channels in the ultra-shallow p-type silicon quantum well (Si-QW), 2 nm, confined by the δ-barriers heavily doped with boron on the n-type Si (100) surface. This longitudinal quantum conductance staircase, Gxx, is revealed by the voltage applied to the Hall contacts, Vxy, to a maximum of 4e2/h. In addition to the standard plateau, 2e2/h, the variations of the Vxy voltage appear to exhibit the fractional forms of the quantum conductance staircase with the plateaus and steps that bring into correlation respectively with the odd and even fractional values.

Asymptotically Necessary and Sufficient Quadratic Stability Conditions of T-S Fuzzy Systems Using Staircase Membership Function and Basic Inequality

Asymptotically necessary and sufficient quadratic stability conditions of Takagi-Sugeno (T-S) fuzzy systems are obtained by utilizing staircase membership functions and a basic inequality. The information of the membership functions is incorporated in the stability analysis by approximating the original continuous membership functions with staircase membership functions. The stability of the T-S fuzzy systems was investigated based on a quadratic Lyapunov function. The asymptotically necessary and sufficient stability conditions in terms of linear matrix inequalities were derived using a basic inequality. A fuzzy controller was also designed based on the stability results. The derivation process of the stability results is straightforward and easy to understand. Case studies confirmed the validity of the obtained stability results.

A NOVEL SCHEME FOR HIGH POWER HIGH EFFICIENCY INVERTERS

The pulse width modulation (PWM) scheme is used in the staircase waveform inverters. The control strategy and system characteristics are analyzed. While the single pulse width modulation is used, the 12 stairs waveform inverter can achieve the output voltage regulated in a wide range of input voltage as well as the perfect output waveform. A 1 500 V input 80 kVA inverter has been deve loped. Experiments of the 80kVA inverter resulted in that the scheme is a perfect method for the development of high power converters with high efficiency.

Stabilization design for continuous-time Takagi-Sugeno fuzzy systems based on new relaxed conditions

This paper deals with the problem of stabilization design for a class of continuous-time Takagi-Sugeno（T-S）fuzzy systems.New stabilization conditions are derived based on a relaxed approach in which both fuzzy Lyapunov functions and staircase membership functions are used.Through the staircase membership functions approximating the continuous membership functions of the given fuzzy model,the information of the membership functions can be brought into the stabilization design of the fuzzy systems,thereby significantly reducing the conservativeness in the existing stabilization conditions of the T-S fuzzy systems.Unlike some previous fuzzy Lyapunov function approaches reported in the literature,the proposed stabilization conditions do not depend on the time-derivative of the membership functions that may be the main source of conservatism when considering fuzzy Lyapunov functions analysis.Moreover,conditions for the solvability of the controller design are written in the form of linear matrix inequalities,but not bilinear matrix inequalities,which are easier to be solved by convex optimization techniques.A simulation example is given to demonstrate the validity of the proposed approach.

V-Shaped Monopole Antenna with Chichena Itzia Inspired Defected Ground Structure for UWB Applications

Due to rapid growth in wireless communication technology,higher bandwidth requirement for advance telecommunication systems,capable of operating on two or higher bands with higher channel capacities and minimum distortion losses is desired.In this paper,a compact Ultra-Wideband(UWB)V-shaped monopole antenna is presented.UWB response is achieved by modifying the ground plane with Chichen Itzia inspired rectangular staircase shape.The proposed V-shaped is designed by incorporating a rectangle,and an inverted isosceles triangle using FR4 substrate.The size of the antenna is 25 mm×26 mm×1.6 mm.The proposed V-shaped monopole antenna produces bandwidth response of 3 GHz Industrial,Scientific,and Medical(ISM),Worldwide Interoperability for Microwave Access(WiMAX),(IEEE 802.11/HIPERLAN band,5G sub 6 GHz)which with an additional square cut amplified the bandwidth response up to 8 GHz ranging from 3.1 GHz to 10.6 GHz attaining UWB defined by Federal Communications Commission(FCC)with a maximum gain of 3.83 dB.The antenna is designed in Ansys HFSS.Results for key performance parameters of the antenna are presented.The measured results are in good agreement with the simulated results.Due to flat gain,uniform group delay,omni directional radiation pattern characteristics and well-matched impedance,the proposed antenna is suitable for WiMAX,ISM and heterogeneous wireless systems.

Time-Dependent Variational Approach to the Phonon Dispersion Relation of the Commensurate Quantum Frenkel-Kontorova Model

The phonon dispersion relation of the commensurate quantum Frenkel-Kontorova model is studied by means of the time-dependent variational approach combined with a Hartree-type many-body trial wavefunction for the particles. The single-particle state is taken to be a frozen Jackiw-Kerman wavefunction. Under the condition of minimum uncertainty, equations of motion for the particle expectation values are derived to obtain the phonon dispersion relation. It is shown that the strength of the substrate potential and the phonon excitation gap are reduced due to the quantum fluctuations in comparison with those of the classical model. We also compare our results with those previously obtained by using the path-integral molecular dynamics.

Observational analysis of the double-diffusive convection in the deep Canada Basin

The Canada Basin （CB） is the largest sub-basin in the Arctic, with the deepest abyssal plain of 3 850 m. The double-diffusive process is the possible passage through which the geothermal energy affects the above isolated deep waters. With the temperature-salinity-pressure observations in 2003, 500-m-thick transition layers and lower 1 000-m-thick bottom homogenous layers were found below 2 400 m in the central deep CB. Staircases with downward-increasing temperature and salinity are prominent in the transition layers, suggesting the double- diffusive convection in deep CB. The interface of the stairs is about 10 m thick with 0.001-0.002℃ temperature difference, while the thicknesses of the homogenous layers in the steps decrease upward from about 60 to 20 m. The density ratio in the deep central CB is generally smaller than 2, indicating stronger double-diffusive convection than that in the upper ocean of 200-400 m. The heat flux through the deepest staircases in the deep CB varies between 0.014 and 0.031 W/m2, which is one-two orders smaller than the upper double-diffusive heat flux, but comparable to the estimates of geothermal heat flux.

Novel image restoration model coupling gradient fidelity term based on adaptive total variation

A novel image restoration model coupling with a gradient fidelity term based on adaptive total variation is proposed in this paper. In order to choose proper parameters, the selection criteria were analyzed theoretically, and a simple scheme to demonstrate its validity was adopted experimentally. To make fair comparisons of performances of three models, the same numerical algorithm was used to solve partial differential equations. Both the international standard test image on Lena and HR image of CBERS-02B of Dalian city were used to verify the performance of the model. Experimental results illustrate that the new model not only preserved the edge and important details but also alleviated the staircase effect effectively.

Fractional Fourier transform of Cantor sets: further numerical study

This paper is a further work of the authors＇ paper published previously （Liao T H and Gao Q 2005 Chin. Phys. Lett. 22 2316）. The amplitudes of fractional Fourier transform of Cantor sets are analysed from the viewpoint of multifractal by wavelet transform maxima method （WTMM）. An integral operation is carried out before the application of WTMM, such that the function obtained can be considered as the perturbed devil staircase. Also, wavelets with large number of vanishing moments are used, which makes the complete singularity spectrum more accessible. The validity of multifractal formalism is guaranteed by restricting parameter q to a proper range, so that the phenomenon of multifractal phase transition can be explained reasonably. Particularly, the method of determining the range of parameter q in the above paper is developed to be more operational and rigorous.

Study on tapered crossed subwavelength gratings by Fourier modal method

Fourier modal method incorporating staircase approximation is used to study tapered crossed subwavelength gratings in this paper. Three intuitive formulations of eigenvalue functions originating from the prototype are presented, and their convergences are compared through numerical calculation. One of them is found to be suitable in modeling the diffraction efficiency of the circular tapered crossed subwavelength gratings without high absorption, and staircase approximation is further proven valid for non-highly-absorptive tapered gratings. This approach is used to simulate the ＂moth-eye＂ antireflection surface on silicon, and the numerical result agrees well with the experimental one.

Some minimax theorems with strictly monotone transformation

Some two-function minimax theorems are proved. In these results, the staircase and quantitative-topological conditions of both functions involve strictly monotone transformation and mixing of functional values. Consequently, Lin Quan and Kindler＇s minimax theorems are generalized.

Effect of Acetone Vapor Smoothing Process on Surface Finish and Geometric Accuracy of Fused Deposition Modeling ABS Parts

FDM is a widely used additive manufacturing process, however, it has some limitations, such as surface finish, due to the staircase effect caused by the layer-by-layer deposition. Studies have been conducted on surface finish of ABS parts with the use of acetone, but the process parameters and the resulting effects have not been fully investigated in the literature. Therefore, the aim of this study was to investigate the effects of acetone vapor smoothing process on surface finish and geometric accuracy of fused deposition modeling ABS parts. Specimens with different geometries were created and printed using two directions in different scales. The parts were exposed to acetone vapor for 20, 30 and 40 minutes. 3D deviation maps, roughness and microscopic analyses were conducted. The staircase effect was reduced at the expense of some geometric deviations, which varied according to the exposure time and part orientation. The smoothing process applied to the flat surfaces proved to be quite effective in reducing roughness by 90%, however, this reduction led to an undesirable rounding of the sharp edges. The results obtained in this study are consistent with those found in the literature and may help improve the quality of the ABS printed parts.