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In this paper, we study non-wandering homeomorphisms of the two-dimen-sional torus homotopic to the identity, whose rotation sets are non-trivial segments from (0, 0) to some totally irrational point (α, β). We show that for any r ⩾ 1, this rotation set only appears for C r diffeomorphisms satisfying some degenerate conditions. And when such a rotation set does appear, assuming several natural conditions that are generically satisfied in the area-preserving world, we give a clearer description of its rotational behaviour. More precisely, the dynamics admits bounded deviation along the direction −(α, β) in the lift, and the rotation set is locked inside an arbitrarily small cone with respect to small C 0-perturbations of the dynamics. On the other hand, for any non-wandering homeomorphism f with this kind of rotation set, we also present a perturbation scheme in order for the rotation set to be eaten by the rotation set of some nearby dynamics, in the sense that the later set has non-empty interior and contains the former one. These two flavours interplay and share the common goal of understanding the stability/instability properties of this kind of rotation set.

A high-temperature conductive silver slurry containing lead-free ZnO-B2O3-SiO2 glass for metallization of ceramic MgTiO3 substrate has been prepared. The ZnO-B2O3-SiO2 glass was obtained by high-temperature melting and cold extraction with a transition temperature (Tg) of 579 °C and thermal stability (∆T) of 105 °C as an inorganic bonding phase of high-temperature conductive silver paste. Then, silver paste with different glass powder content was sintered on ceramic MgTiO3 substrate between 730 °C and 930 °C in increments of 50 °C. Characterization of the prepared materials revealed that their resistivity increases with the increase in glass powder content and decreases with the increase in sintering temperature. Sintering temperature and glass content have significant effects on the resistivity and adhesion of the thick silver film. When the silver paste with a glass content of 1.1 wt% was sintered at 830 °C for 10 min, the resulting thick silver film had a low resistivity of 1.81 μΩ·cm (1.65 μΩ·cm for silver) and a good adhesive strength of 39.4 N mm−2. During the sintering process, the glass material melts and wets the silver powder, which promotes the sintering of the silver powder to form a dense network structure and improves the electrical conductivity of the silver film. In addition, the formation of ZnTiO3 by chemical reactions between the glass and the substrate was observed, which dramatically improved the bonding strength of the silver film. Therefore, lead-free silver paste containing ZnO-B2O3-SiO2 glass powder and MgTiO3 ceramics has broad development prospects in ceramic filters.

We perform a lattice QCD calculation of the decay width using a model-independent method that does not require the momentum extrapolation of corresponding off-shell form factors. The simulation is performed on ensembles of twisted mass lattice QCD gauge configurations with three different lattice spacings. After the continuum extrapolation, the decay width is obtained to be . Regardless of this large statistical error, our result is compatible with the experimental results within 1.3σ. Potential improvements of the lattice calculation in the future are also discussed.

With the development of the Power Internet of Things, power transmission and transformation business have a wide range of operation, large regional differences, a wide variety of equipment and other problems, making the access and deployment of mass sensors with low power consumption crucial. In order to realize the cloud-side collaborative computing of the Internet of Things, it is necessary to build a low-power information acquisition and transmission network, and realize the low-power deployment of the low-power sensor network and equipment. The embedded node device can be used as the basis of low-power transmission network to realize low-power transmission of cloud-side collaborative computing information, combined with the existing low-power transmission and transformation equipment.

The power consumption readings of sub meter and total meter of distribution transformer of low-voltage users follow the law of conservation of energy. The meter power loss rate of abnormal low-voltage users must also be abnormal. This paper studies the solution of the meter power loss rate under the four abnormal power consumption scenarios of single (multi) user and full (partial) period. The traditional linear solution method has accurate identification effect for the abnormal power consumption scenario of full period, but it cannot identify the abnormal power consumption scenario of partial period. In this paper, an improved artificial fish swarm algorithm is proposed. By adjusting the fixed step to the adaptive step, the power loss rate of each sub meter is obtained, and the abnormal power users are pinpointed. The research results are verified by simulation examples on IEEE European Low Voltage Test Feeder. The results show that the improved artificial fish swarm algorithm in this paper can identify abnormal power users for the above four abnormal electric field scenarios. The algorithm provides a new alternative for the identification of abnormal low voltage users.

X-ray photodetection are frequently used in medical diagnoses industrial inspection and environmental radiation detection. Currently, there is an ongoing effort to develop bendable or flexible x-ray photodetectors (PDs) to meet the demand on light weight and arbitrary shape detection system. Here, a highly bendable indirect x-ray PD is designed by coupling a P3HT:PC61BM organic photodetectors (OPDs) with a flexible perovskite quantum dots (QDs) embedded polymer scintillator. The flexible perovskite QDs scintillator exhibits high radioluminescence with emission peak centers at the 537 nm, which falls in maximum absorption range of poly(3-hexylthiophene) (P3HT). The OPD, with 2 μ m active layer, exhibits low dark currents in the range of tens of nanoampere per square centimeter over a wide reversed biased range. The OPD demonstrates detectable light signal down to 0 .1 μ W cm − 2 and low dose detection capability. The coupling of perovskite QDs scintillator and OPD shows a sensitivity of 638 e nGy−1 mm−2 10 .2 μ C G y − 1 c m − 2 at a dose rate of 1 mGy s−1, which brings the possibilities of realizing highly bendable x-ray PDs.

Our previous sparse regularization method for multipath interference (MPI) compensation in pulsed Time-of-Flight (ToF) depth camera works well on desktop computer. However, pulsed ToF depth cameras are mainly applied in fields such as autopilot vehicles and robots. In these situations, exporting depth images to a computer and running MPI compensation in MATLAB every time are not realistic. Therefore, according to the hardware structure of the multipath interference real-time compensation platform, we use QR decomposition to optimize the sensing matrix in our algorithm for better hardware implementation, while maintaining the accuracy of our algorithm. For the optimized algorithm, we designed an efficient parallel data processing hardware structure that matches the features of our algorithm to optimize the calculation efficiency. Then, we implemented it on the realtime compensation platform. The experimental results show that this algorithm architecture runs stably under the clock frequency and it runs faster than desktop computer.

Single crystal rare-earth magnets, such as hexagonal-close-packed gadolinium, usually have a large second order anisotropy K 2 and a negative first order anisotropy K 1 at low temperatures, which are difficult to explain using microscopic theories. An atomic scale effective spin Hamiltonian ℱ[{ S i }] is proposed, which, apart from the usual isotropic nearest neighbor coupling J, consists of two new terms that are different for in-plane and out-of-plane neighbors and which are characterized by two new couplings C 1 and C 2, respectively. The hybrid Monte–Carlo method is utilized to sample this system to the desired Boltzmann-like distribution exp(−ℱ/k B T). It is found that K 2 and K 1 are compatible with the experimental values and arise naturally from the exchange anisotropy C 1 and C 2, which are less than 0.01 in magnitude of the isotropic exchange energy J. This new model spin Hamiltonian can also be applied to study other magnetic properties.

With the increasing number of non-linear loads and impact loads in the actual power grid, power quality problems are becoming more and more serious. Accurate and rapid identification of power quality disturbance signals is of great significance for improving the power quality and ensuring stable operation of the power grid. For this reason, this paper proposes a multi-resolution analysis of wavelet transform and a combination of sample entropy to extract the characteristics of power quality disturbance signals. The classification effect is better than the initial samples. The weighted optimization random forest classifier is used to classify the features, which reduces the error caused by the mode voting method of the random forest. The simulation and actual test results show that the power quality disturbances detection algorithm based on sample entropy and weighted optimization random forest has better classification accuracy than the decision tree, extreme random tree and traditional random forest.

With the continuous development of the economy, the pollution of heavy metals to the environment is becoming more and more serious. It is more and more urgent to study the migration and transformation of heavy metals. This paper reviews the classification of heavy metal migration and transformation models, which can be divided into: chemical thermodynamic model, chemical reaction kinetics model, migration and transformation kinetic model (overall model, phase separation model, empirical model), and introduces the applications of the model in different aspects.

Vector meson mass values are studied at finite chemical potential and temperature in lattice QCD with lattice size of 24 × 122 × 6 using two flavors of staggered quarks. The investigation focuses on the change of the vector meson mass in the critical region close to Tc with two different types of chemical potentials switched on: the isoscalar chemical potential μs and its isovector counterpart μv. It is found that the vector meson mass increases in the QGP phase with both chemical potentials and decreases with μs in the confinement phase.

In the torsion pendulum experiments, the thermal noise sets the most fundamental limit to the accurate estimation of the amplitude of the signal with known frequency. The variance of the conventional method can meet the limit only when the measurement time is much longer than the relaxation time of the pendulum. By using the maximum likelihood estimation and the equation-of-motion filter operator, we propose an optimal (minimum variance, unbiased) amplitude estimation method without limitation of the measurement time, where thermal fluctuation is the leading noise. While processing the experimental data tests of the Newtonian gravitational inverse square law, the variance of our method has been improved than before and the measurement time of determining the amplitude with this method has been reduced about half than before for the same uncertainty. These results are significant for the torsion experiment when the measurement time is limited.

Schottky photodiodes, which are based on metal-semiconductor junctions, are one of the most widely used technologies for low cost image sensor arrays. Here, we fabricate a hole transport layer free organolead halide perovskite diode (ITO/CH3NH3PbI3/PCBM/BCP/Ag), and explore its Schottky diode behavior. A Schottky barrier is identified between the transparent conductor ITO and the solution processed perovskite (CH3NH3PbI3), with a barrier height of ~0.97 eV measured by capacitance-voltage (C-V) measurements. The Schottky barrier at the ITO/CH3NH3PbI3 junction is found to effectively suppress electron injection from ITO to the perovskite under reversed bias, leading to a surprising low dark current of 1.9 × 10−9 A cm−2 when biased at −0.1 V. When functioning as a photodetector, the ITO/CH3NH3PbI3 Schottky diode outperforms the conventional perovskite photodiode with PEDOT:PSS layer in terms of detectivity, reaching a high specific detectivity (D*) of 8.9 × 1012 Jones. Moreover, by tuning the band gap of perovskite with the content of bromine (Br), i.e. CH3NH3Pb (I1−XBrX) 3(0 ≤ x ≤ 1), the Schottky barrier height at the ITO/perovskite junction is raised, further lowering the dark current of the perovskite photodiode. This work provides fundamental investigation on the device physics of the perovskite Schottky diode, as well as a low cost approach for designing the high sensitivity of photodetectors.

Virtual reality technology has been widely used by constructing a virtual space to simulate and restore the real world. The system uses 3ds MAX and Unity3D software to establish a 500kV substation virtual simulation system. The system completely establishes the 3D models of primary and secondary equipment of 500kV substations, and truly restores the overall layout of the substations. At the same time, the Unity3D engine, VR technology and interactive equipment are used at the same time to make this system able to provide trainees with an immersive training experience, which is more realistic than the application over the same period. The system completes the realization of substation training, station roaming and fault simulation functions, including substation equipment technical parameter display and synchronous voice introduction, interface design, basic operation, and fault phenomenon simulation; the infrastructure of the system is developed well and has strong expandability, which lays a foundation for subsequent function development. This system satisfies the substation training needs and can be used for related staff training of substations and to help students in electrical major to gain cognitive learning.

Electron transport layer (ETL) plays an important role in realizing efficient and stable perovskite solar cells (PSCs). There are continuous efforts in developing new types of low cost ETLs with improved conductivity and compatibility with perovskite and the conducting electrode. Here, in order to obtain high efficient and stable PSCs on ZnO:Al (AZO) substrate, reduced graphene oxide (rGO) is incorporated into SnO2 nanoparticles to form composite ETL. For planar PSC on AZO substrates, SnO2-rGO with a low incorporation ratio of 3 wt% rGO significantly enhances the device short circuit current density (J sc) and the fill factor when compared to the device with pristine SnO2 ETL, leading to an overall power conversion efficiency of 16.8% with negligible hysteresis. The effectiveness of the excited charge transfer process of SnO2-rGO ETL is revealed by time-resolved photoluminescence decay, and by electrochemical impedance spectrum measurements. Furthermore, the solar cell stability is also enhanced due to the incorporation of rGO in the ETL. This work provides a low cost and effective ETL modification strategy for achieving high performance planar PSCs.

BEPC II is a double ring e+e− collider with high beam currents and luminosity, so the high beam-related backgrounds may disturb the detector. In order to have a good quality of data taking, backgrounds should be kept at a level as low as possible. A series of collimators are designed and installed in both the e+ and e− rings. Two of the collimators are horizontally movable, each for one ring, about 8 m upstream from the interaction point. Experiments have been done to identify the effectiveness of the movable collimators with different apertures and beam currents. The results show that the movable collimators are very effective and can reduce as much as about 50% of beam-related backgrounds.

The lowest-lying glueballs are investigated in lattice QCD using $N_f=2$ clover Wilson fermion on anisotropic lattices. We simulate at two different and relatively heavy quark masses, corresponding to physical pion mass of $m_\pi\sim 938$ MeV and $650$ MeV. The quark mass dependence of the glueball masses have not been investigated in the present study. Only the gluonic operators built from Wilson loops are utilized in calculating the corresponding correlation functions. In the tensor channel, we obtain the ground state mass to be 2.363(39) GeV and 2.384(67) GeV at $m_\pi\sim 938$ MeV and $650$ MeV, respectively. In the pseudoscalar channel, when using the gluonic operator whose continuum limit has the form of $\epsilon_{ijk}TrB_iD_jB_k$, we obtain the ground state mass to be 2.573(55) GeV and 2.585(65) GeV at the two pion masses. These results are compatible with the corresponding results in the quenched approximation. In contrast, if we use the topological charge density as field operators for the pseudoscalar, the masses of the lowest state are much lighter (around 1GeV) and compatible with the expected masses of the flavor singlet $q\bar{q}$ meson. This indicates that the operator $\epsilon_{ijk}TrB_iD_jB_k$ and the topological charge density couple rather differently to the glueball states and $q\bar{q}$ mesons. The observation of the light flavor singlet pseudoscalar meson can be viewed as the manifestation of effects of dynamical quarks. In the scalar channel, the ground state masses extracted from the correlation functions of gluonic operators are determined to be around 1.4-1.5 GeV, which is close to the ground state masses from the correlation functions of the quark bilinear operators. In all cases, the mixing between glueballs and conventional mesons remains to be further clarified in the future., Comment: 14 pages, 8 figures, 9 tables; typos fixed, minor modifications, match the published version

The structural, magnetic and transport properties of the compounds Sr2(Fe1−xMnx)MoO6 (0 ≤ x ≤ 0.45) have been studied. The saturated magnetization, Curie temperature and low-field magnetoresistance of the compounds decrease with x, while the resistivity increases by several orders of magnitude when x exceeds a critical value. A positive magnetoresistance has been observed for x = 0.45. A possible percolation mechanism is proposed to elucidate the observations; it also suggests a coexistence of (Mn3+, Mo5+) and (Mn2+, Mo6+) valence pairs and a saturated substitution of Mn3+ for Fe3+.

The crystal structure and magnetic and electronic transport properties of the ternary intermediate compound Pr5Si2Ge2 were investigated by means of x-ray powder diffraction, magnetic and electrical resistance measurements. The compound has two polymorphs: alpha-Pr5Si2Ge2 crystallizing in a monoclinic structure with space group P112(1)/a, for the as-cast sample, and alpha-Pr5Si2Ge2 crystallizing in a tetragonal structure with space group P4(1)2(1)2, for. the sample annealed at 1273 K. The average interatomic distances of magnetic Pr atoms and the amounts of covalent (Si, Ge)-(Si, Ge) bond pairs in these two phases are different, which may be, responsible for their different magnetic properties. The Curie temperatures T-C of alpha-Pr5Si2Ge2 and beta-Pr5Si2Ge2 are 38 and 50 K, respectively. An irreversibility between zero-field-cooling and field-cooling magnetization curves is observed. The zero-field resistance of these two phases exhibits an anomaly near T-C. On the basis of the results of magnetic and electrical resistance measurements, it is inferred that both of these phases exhibit spin-glass-like behaviour. The magnetic properties and structure dependence of the Pr5Si2Ge2 can be elucidated well using the Ruderman-Kittel-Kasuya-Yosida model.

In organic thin-film transistors (OTFTs), using high-k dielectrics could increase the accumulated carrier numbers at low operation voltage (i.e. the bulk effect), but may induce extra dipolar disorders to affect the electronic states in organic semiconductors (i.e. the interfacial effect). The two effects are considered together to model charge transport in OTFTs and to give quantitative calculations of the impacts from using high-k dielectrics or hybrid dielectrics, especially the relations between mobility and Fermi-energy, carrier concentrations, or gate-voltage. In experimental studies, zirconium oxide (ZrO2) and yttrium oxide (Y2O3) are fabricated by solution process for high-k dielectrics. The oxide insulating films are modified by low-k polymer layers and the resulting OTFTs show low operation voltage and high performance in ambient test. The highest mobility reaches 2.38 cm2 V−1 s−1 for ZrO2 based OTFT and 3.56 cm2 V−1 s−1 for Y2O3 based OTFT, and the on/off ratio is 1.4 × 104 for ZrO2 devices and 5.4 × 104 for Y2O3 devices. In general, the trends of experimentally measured mobility are consistent with the theoretical calculations, showing the high-k/low-k hybrid dielectrics mainly improve the carrier mobility in the regime of low carrier density.

The oxygen related defects in the solution combustion-processed InZnO vitally affect the field-effect mobility and on-off characteristics in thin film transistors (TFTs). We use photoelectron spectroscopy to reveal that these defects can be well controlled by adjusting the atmosphere and flow rate during the combustion reaction, but are hardly affected by further post-annealing after the reaction. In device performance, the threshold voltage of the InZnO-TFTs was regulated in a wide range from 3.5 V to 11.0 V. To compromise the high field-effect mobility and good subthreshold properties, we fabricate the TFTs with double active layers of InZnO to achieve vertical gradience in defect distribution. The resulting TFT exhibits much higher field-effect mobility as 17.5 cm2 V−1 s−1, a low reversed sub-threshold slope as 0.35 V/decade, and a high on-off ratio as 107. The presented understandings and methods on defect engineering are efficient in improving the device performance of TFTs made from the combustion reaction process.

In this work, p-channel thin film transistors (TFTs) with a nickel oxide (NiO) active layer have been synthesized by a solution combustion process. The effect of synthesis parameters was investigated. It was revealed that the metal–acetylacetone complexes and metal–ammine complexes coexist in the solution precursor. The combustion of metal–acetylacetone complexes is dominant in the redox reaction, while the combustion of metal–ammine complexes completes the reaction of residual organic matter. The proportion of both complexes in the solution precursor is key for NiO synthesis, which is tunable by the precursor aging time. The annealing temperature is another key parameter. X-ray photoelectron spectroscopy analysis indicates that organic residues exist in the film annealed at low temperature. In contrast, with the increase in annealing temperature, the Ni3+-related components decreased while the intensity of Ni2+ in the film increased. This results in a decrease in the hole concentration and the degradation of device performance. The p-channel NiO TFTs with a field-effect mobility of 0.015 cm2 V–1 s–1 have been achieved via systemically optimizing precursor aging time and post-annealing temperature. This study successfully demonstrates the potential of combustion solution-processed NiO TFTs with p-channel characteristics.

The novel nitride with monoclinic structure is synthesized by gas - solid reaction. Its hard magnetic properties have been investigated by ball milling and magnetic measurements. The intrinsic coercivity increases with decreasing average particle size d and, after reaching a maximum at , then decreases slowly. increases also with increasing magnetizing field. A value of has been attained. The magnetizing field for obtaining coercivity saturation is about 1.5 T. The hard magnetic properties of remanence and energy product for are achieved at 293 K.

The $\Omega$ baryons with $J^P=3/2^\pm, 1/2^\pm$ are studied on the lattice in the quenched approximation. Their mass levels are ordered as $M_{3/2^+}, Comment: 7 pages, 5 figures, submitted to Chinese Physics C

The threshold voltage shift (ΔV th) under positive gate bias stress (PGBS), generally found in amorphous InGaZnO thin-film transistors (a-IGZO TFTs), has usually been suppressed by external passivation layers. We report it can also be alleviated by the self-passivation effect of the active layer, where moderately increasing the active layer thickness (d s) reduces ΔV th by 82% in SiO x -passivated a-IGZO TFTs. Our experiments in conjunction with simulations show that the instability of V th comes from ambient factors at the back channel. Larger d s results in lower carrier concentrations at the back channel (N back), fewer diffusive ions affecting the front channel, and much more stable operations under PGBS. The optimal thickness of an IGZO film simultaneously obtaining a small ΔV th, near-zero V th, and sharp sub-threshold swing is about 80–90 nm, thicker than those usually adopted. The self-passivation effect combined with the externally deposited passivation layer can improve the overall device reliability.

R3(Fe, Ti)29Cy carbides (R=Nd, Sm) have been synthesized by gas-solid phase reaction. The Curie temperature is enhanced by carbonation, with values of 651 K and 641 K for Nd and Sm carbides respectively. The saturation magnetization of the carbides is slightly lower than that of their parent alloys. The Sm carbide has a large uniaxial anisotropy field, 21 T at 4.2 K and 14 T at 293 K. A coercivity of mu 0iHc=0.3 T at room temperature in the Sm carbide has been developed.

The magnetocrystalline anisotropy of YFe12-xMox and YPe12-xMoxNy (x=1-3, y approximately=1) have been investigated by X-ray diffraction and the singular point detection technique. The uniaxial anisotropy of the YFe12-xMox series decreases with increasing Mox concentration with a clear turning point at about x=1.6. The anisotropy characteristic of the nitride YFe12-xMoxNy changes into a canted-type anisotropy for x or=1.5. The anisotropy reduction for YFe12-xMox is mainly due to the substitution of Mox atoms on the 8i sites, while the further change in anisotropy for YFe12-xMoxNy may be due to a change in the 3d orbital moment or to a change in crystal-field interaction by the interstitial Ny atoms.

Solution-processed p-type metal oxide materials have shown great promise in improving the stability of perovskite-based solar cells and offering the feasibility for a low cost printing fabrication process. Herein, we performed a device modeling study on planar perovskite solar cells with cuprous oxide (Cu2O) hole transporting layers (HTLs) by using a solar cell simulation program, wxAMPS. The performance of a Cu2O/perovskite solar cell was correlated to the material properties of the Cu2O HTL, such as thickness, carrier mobility, mid-gap defect, and doping concentrations. The effect of interfacial defect densities on the solar cell performance was also investigated. Our simulation indicates that, with an optimized Cu2O HTL, high performance perovskite solar cells with efficiencies above 13% could be achieved, which shows the potential of using Cu2O as an alternative HTL over other inorganic materials, such as NiOx and MoOx. This study provides theoretical guidance for developing perovskite solar cells with inorganic hole transporting materials via a printing process.

In solution-processed organic field-effect transistors (OFETs), the polymers with high level of lowest unoccupied molecular orbitals (LUMOs, > −3.5 eV) are especially susceptible to electron-trapping that causes low electron mobility and strong instability in successive operation. However, the role of high-LUMO-level polymers could be different depending on their locations relative to the semiconductor/insulator interface, or could even possibly benefit the device in some cases. We constructed unconventional polymer heterojunction n-type OFETs to control the location of the same polymer with a high LUMO level, to be in, under, or above the accumulation channel. We found that although the devices with the polymer in the channel suffer from dramatic instability, the same polymer causes much less instability when it acts as a dielectric modification layer or charge injection layer. Especially, it may even improve the device performance in the latter case. This result helps to improve our understanding of the electron-trapping and explore the value of these polymers in OFETs.

The ac frequency response characteristics (FRC) of organic thin film transistors and metal-insulator semiconductor diodes were highly improved by controlling the morphology and electrical characteristics of semiconducting pentacene films. The devices with films grown at 50 °C show much higher cutoff frequency and better frequency stability of flat-band voltage, as compared to those with films grown at other temperatures below or above. The improvement mainly originates from the maximum field effect carrier mobility of 0.78 cm2 V−1 s−1 and a small metal/organic contact resistance (Rc) obtained in the optimum thin film transistors. Our results indicate growth temperature precisely tunes the film microstructure and metal/semiconductor interface, which together determine the FRC of pentacene-based organic devices.

The coercivity of the Sm3(Fe,Ti)29Ny nitride is controlled by the nucleation mechanism. The phenomenon of a minimum of the coercivity in the angular dependence of the coercivity is found for the Sm3(Fe,Ti)29Ny nitride. The small magnetizing field required to obtain the saturation coercivity and the small interparticle interaction for the isotropic Sm3(Fe, Ti)29Ny magnet imply that grains of Sm3(Fe, Ti)29Ny are well isolated.

In ground-based extensive air shower experiments, the direction and energy are reconstructed by measuring the relative arrival time of secondary particles, and the energy they deposit. The measurement precision of the arrival time is crucial for determination of the angular resolution. For this purpose, we need to obtain a precise relative time offset for each detector and to apply the calibration process. The time offset is associated with the photomultiplier tube, cable, relevant electronic circuits, etc. In view of the transit time through long cables being heavily dependent on the ambient temperature, a real-time calibration method for the cable transit time is investigated in this paper. Even with a poor-resolution time-to-digital converter, this method can achieve high precision. This has been successfully demonstrated with the Front-End-Electronic board used in the Daya Bay neutrino experiment.

In this paper, we consider the recovery problem of inclusions in three-dimensional and three-dimensional domains for Poisson’s equation from noisy observation data. We propose effective reconstruction algorithms to recover hidden inclusions within a body when one can only make measurements of voltage and current on the external boundary. Our motivation is to detect the number, the location, the size and the shape of inclusions. This problem is nonlinear and severely ill posed, thus we should apply regularization techniques in our approaches in order to improve the corresponding approximation. We give several examples to show the viability of our proposed methods.

Metal-diffusion-induced indium tin oxide (ITO) nanoparticles have been observed at the 2-amino-4,5-dicyanoimidazole (AIDCN)/ITO interface. X-ray photoelectron spectroscopy depth profiles reveal that the indium (In) and tin (Sn) elements of the nanoparticles are diffused from the ITO film into the organic layer. And the bonding states of In and Sn in the nanoparticles are identified to be In2O3 and SnO2, respectively. Furthermore, it is found that the ITO nanoparticles have an influence on the electrical property, causing electrical switching behaviour in the Al/AIDCN/ITO sandwich structure.

Charge trapping at organic/self-assembly molecule (SAM) interfaces is studied by the electrical switching behaviour in a crosspoint structure, where interfacial charge trapping tunes the potential barrier of the SAM layer. The sample with rubrene exhibits the write-once read-many-times memory effect, which is due to the interfacial charges trapped at deep states. On the other hand, the sample with 2-amino-4,5-dicyanoimidazole presents recyclable conduction transition, which results from the trapped charges distributed at shallow states. Moreover, the percentage of the charges trapped at shallow states can be estimated from electrical transition levels.

Spontaneous symmetry breaking is a cooperative phenomenon for systems with infinitely many degrees of freedom and it plays an essential role in quantum field theories. Lattice O(N) model is studied within the Hamiltonian approach using an adiabatic approximation. It is shown that the low-lying spectrum of the system in the broken phase can be understood by using the adiabatic, or Born-Oppenheimer approximation, which turns out to become an expansion in the inverse power of volume. In the infinite volume limit, the symmetry is broken while in the finite volume the slow rotation of the zero-momentum mode restores the symmetry and gives rise to the rotator spectrum, which has been observed in realistic Monte Carlo simulations.