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Let $Ω$ be a bounded domain in $\mathbb{R}^2$ with smooth boundary, we study the following anisotropic elliptic Neumann problem with Hardy-Hénon weight $$ \begin{cases} -\nabla(a(x)\nabla u)+a(x)u=a(x)|x-q|^{2α}u^p,\,\,\,\, u>0\,\,\,\,\, \textrm{in}\,\,\,\,\, Ω,\\[2mm] \frac{\partial u}{\partialν}=0\,\, \qquad\quad\qquad\qquad\qquad \qquad\qquad\qquad\qquad \,\ \ \,\,\,\, \textrm{on}\,\,\, \partialΩ, \end{cases} $$ where $ν$ denotes the outer unit normal vector to $\partialΩ$, $q\in\overlineΩ$, $α\in(-1,+\infty)\setminus\mathbb{N}$, $p>1$ is a large exponent and $a(x)$ is a positive smooth function. We investigate the effect of the interaction between anisotropic coefficient $a(x)$ and singular source $q$ on the existence of concentrating solutions. We show that if $q\inΩ$ is a strict local maximum point of $a(x)$, there exists a family of positive solutions with arbitrarily many interior spikes accumulating to $q$; while if $q\in\partialΩ$ is a strict local maximum point of $a(x)$ and satisfies $\langle\nabla a(q),\,ν(q)\rangle=0$, such a problem has a family of positive solutions with arbitrarily many mixed interior and boundary spikes accumulating to $q$. In particular, we find that concentration at singular source $q$ is always possible whether $q\in\overlineΩ$ is an isolated local maximum point of $a(x)$ or not., This manuscript has been accepted for publication in Topological Methods in Nonlinear Analysis(TMNA). arXiv admin note: text overlap with arXiv:1904.02936

Scheme S1. The synthetic route to prepare PTMM, TTNA, and TTBI. Figure S1 1 H NMR spectrum of PM. Figure S2 1 H NMR spectrum of PTMM. Figure S3 13 C NMR spectrum of PTMM. Figure S4. LC-MS spectrum of PTMM. Figure S5 1 H NMR spectrum of TTA. Figure S6 1 H NMR spectrum of TTNA. Figure S7 13 C NMR spectrum of TTNA. Figure S8. MALDI-TOF-MS spectrum of TTNA. Figure S9 1 H NMR spectrum of TTBI. Figure S10. 13 C NMR spectrum of TTBI. Figure S11. LC-MS spectrum of TTBI. Figure S12. The absorption spectrum of AIEgens in different solvents. Figure S13. PL spectra of AIEgens of AIEgens with different water fractions. Table S1. Comparison of absorption and emission peak between experimental and ML predicted. Table S2. Particle size of AIEgens NPs. Table S3. Zeta potentials of AIEgens NPs. Figure S14. Calculated LUMO and HOMO of PTMM, TTNA, and TTBI. Figure S15. Z-stack images of phantom of PTMM NPs. Figure S16. Z-stack images of phantom of TTNA NPs. Figure S17. Z-stack images of phantom of TTBI NPs. Figure S18. Experimental and predicted data are compared using 10-fold cross-validation. Figure S19. ML prediction error distribution. Figure S20. Model scalability. Figure S21. Comparison of ML accuracy and TD-DFT. Figure S22. Illustration of 10-fold cross-validation.

The potential advantages of intelligent wireless communications with millimeter wave (mmWave) and massive multiple-input multiple-output (MIMO) are based on the availability of instantaneous channel state information (CSI) at the base station (BS). However, no existence of channel reciprocity leads to the difficult acquisition of accurate CSI at the BS in frequency division duplex (FDD) systems. Many researchers explored effective architectures based on deep learning (DL) to solve this problem and proved the success of DL-based solutions. However, existing schemes focused on the acquisition of complete CSI while ignoring the beamforming and precoding operations. In this paper, we propose an intelligent channel feedback architecture using eigenmatrix and eigenvector feedback neural network (EMEVNet). With the help of the attention mechanism, the proposed EMEVNet can be considered as a dual channel auto-encoder, which is able to jointly encode the eigenmatrix and eigenvector into codewords. Simulation results show great performance improvement and robustness with extremely low overhead of the proposed EMEVNet method compared with the traditional DL-based CSI feedback methods.

The initiation, expansion, and penetration of microscopic cracks in rock is the macroscopic manifestation of creep. This paper investigates mechanical creep characteristics and fracture evolution processes in rock masses with different fracture angles, lengths, and rock bridge dip angles. Single fractures, dual parallel fractures, and fracture groups are considered. The approach comprises discrete element simulation based on continuum mechanics, utilizing the continuous and discontinuous software, GDEM. Single-fracture rock masses are characterized by a progressive fracture development mode dominated by tensile shear failure. The rate of creep and fracture magnitude both increase according to fracture length. With increasing fracture inclination angle, creep rate and fracture magnitude increase and decrease. The creep rate and degree of rupture are highest for fractures inclined at 30°. The dual-fracture rock mass exhibits both tensile crack failure and compressional shear failure. Creep rates are highest, and rupture effects are most apparent at rock bridge inclination angles of 90°. If the rock bridge is too long or too short, the stable creep stage is prolonged, but the creep acceleration stage intensifies due to interaction between fracture-bounded rock masses. The failure mode, in this case, involves collective failure by tension fractures and compressional shear. Creep rate and fracture magnitude increase with the number of fractures, which accelerates rock mass deformation to a certain extent. However, when the number of fractures reaches a certain threshold, a relatively stable structure may become established, slowing down the creep rate, especially during the creep acceleration stage. This study can provide a theoretical basis and reference for investigating the creep rupture law of rock mass engineering and the prevention and control of fractured rock mass geological disasters.

Radio Frequency Fingerprint (RFF) identification on account of deep learning has the potential to enhance the security performance of wireless networks. Recently, several RFF datasets were proposed to satisfy requirements of large-scale datasets. However, most of these datasets are collected from 2.4G WiFi devices and through similar channel environments. Meanwhile, they only provided receiving data collected by the specific equipment. This paper utilizes software radio peripheral as a dataset generating platform. Therefore, the user can customize the parameters of the dataset, such as frequency band, modulation mode, antenna gain, and so on. In addition, the proposed dataset is generated through various and complex channel environments, which aims to better characterize the radio frequency signals in the real world. We collect the dataset at transmitters and receivers to simulate a real-world RFF dataset based on the long-term evolution (LTE). Furthermore, we verify the dataset and confirm its reliability. The dataset and reproducible code of this paper can be downloaded from GitHub link: https://github.com/njuptzsp/XSRPdataset.

Millimeter wave (mmWave) communication technique has been developed rapidly because of many advantages of high speed, large bandwidth, and ultra-low delay. However, mmWave communications systems suffer from fast fading and frequent blocking. Hence, the ideal communication environment for mmWave is line of sight (LOS) channel. To improve the efficiency and capacity of mmWave system, and to better build the Internet of Everything (IoE) service network, this paper focuses on the channel identification technique in line-of- sight (LOS) and non-LOS (NLOS) environments. Considering the limited computing ability of user equipments (UEs), this paper proposes a novel channel identification architecture based on eigen features, i.e. eigenmatrix and eigenvector (EMEV) of channel state information (CSI). Furthermore, this paper explores clustered delay line (CDL) channel identification with mmWave, which is defined by the 3rd generation partnership project (3GPP). Ther experimental results show that the EMEV based scheme can achieve identification accuracy of 99.88% assuming perfect CSI. In the robustness test, the maximum noise can be tolerated is SNR= 16 dB, with the threshold acc \geq 95%. What is more, the novel architecture based on EMEV feature will reduce the comprehensive overhead by about 90%.

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Given a smooth bounded domain $\Omega$ in $\mathbb{R}^2$, we study the following anisotropic Neumann problem $$ \begin{cases} -\nabla(a(x)\nabla u)+a(x)u=\lambda a(x) u^{p-1}e^{u^p},\,\,\,\, u>0\,\,\,\,\, \textrm{in}\,\,\,\,\, \Omega,\\[2mm] \frac{\partial u}{\partial\nu}=0\,\, \qquad\quad\qquad\qquad\qquad\qquad\qquad \ \ \ \ \,\qquad\quad\, \textrm{on}\,\,\, \partial\Omega, \end{cases} $$ where $\lambda>0$ is a small parameter, $0

With the development of the high power laser facilities, laser resistance of pulse compression grating is getting increased attention. The metal dielectric mixed grating (MDMG) is widely studied, because it has wide diffraction bandwidth, low surface stress and potential high threshold. The effect of nodular defect size on damage of MDMG is studied by experiments and theoretical analysis in two typical cases. The initial damages appear in the district of nodular defect due to local electric field enhancement induced by nodular defect, which is different with the initial damage located in grating pillar of the perfect MDMG. Laser induced ionization theory is introduced to describe the damage process and give a quantitative analysis on the relationship of laser damage and nodular defect size. It is concluded that local electric field enhancement in nodular defect area would cause the electron density to reach the critical value and lead to the damage occurrence, and nodule damage critical diameters are 1400 nm and 1500 nm respectively in case 1 (seed under the grating pillar) and case 2 (seed under the grating groove) which will lead to nodule damage initiation.

Power electronic converters play a key role in power generation, storage, and consumption. The major portion of power losses in the converters is dissipated in the semiconductor switching devices. In recent years, new power semiconductors based on wide band-gap (WBG) devices have been increasingly developed and employed in terms of promising merits including the lower on-state resistance, lower turn-on/off energy, higher capable switching frequency, higher temperature tolerance than conventional Si devices. However, WBG devices also brought new challenges including lower fault tolerance, higher system cost, gate driver challenges, and high dv/dt and resulting increased bearing current in electric machines. This work first proposed a hybrid "Si IGBTs + SiC MOSFETs" five-level transistor clamped H-bridge (TCHB) inverter which required significantly fewer number of semiconductor switches and fewer isolated DC sources than the conventional cascaded H-bridge inverter. As a result, system cost was largely reduced considering the high price of WBG devices in the present market. The semiconductor switches operated at carrier frequency were configured as Silicon Carbide (SiC) devices to improve the inverter efficiency, while the switches operated at fundamental output frequency (i.e., grid frequency) were constituted by Silicon (Si) IGBT devices. Different modulation strategies and control methods were developed and compared. In other words, this proposed "SiC+Si" hybrid TCHB inverter provided a solution to ride through a load short-circuit fault. Another special power electronic, multiport converter, was designed for EV charging station integrated with PV power generation and battery energy storage system. The control scheme for different charging modes was carefully developed to improve stabilization including power gap balancing, peak shaving, and valley filling, and voltage sag compensation. As a result, the influence on the power grid was reduced due to the matching between daily charging demand and adequate daytime PV generation. For special machine drives, such as slotless and coreless machines with low inductance, low core losses, typical drive implementations using conventional silicon-based devices are performance limited and also produce large current and torque ripples. In this research, WBG devices were employed to increase inverter switching frequency, reduce current ripple, reduce filter size, and as a result reduce drive system cost. Two inverter drive configurations were proposed and implemented with WBG devices in order to mitigate such issues for 2-phase very low inductance machines. Two inverter topologies, i.e., a dual H-bridge inverter with maximum redundancy and survivability and a 3-leg inverter for reduced cost, were considered. Simulation and experimental results validated the drive configurations in this dissertation. An integrated AC/AC converter was developed for 2-phase motor drives. Additionally, the proposed integrated AC/AC converter was systematically compared with commonly used topologies including AC/DC/AC converter and matrix converters, in terms of the output voltage/current capability, total harmonics distortion (THD), and system cost. Furthermore, closed-loop speed controllers were developed for the three topologies, and the maximum operating range and output phase currents were investigated. The proposed integrated AC/AC converter with a single-phase input and a 2-phase output reduced the switch count to six and resulting in minimized system cost and size for low power applications. In contrast, AC/DC/AC pulse width modulation (PWM) converters contained twelve active power semiconductor switches and a common DC link. Furthermore, a modulation scheme and filters for the proposed converter were developed and modeled in detail. For the significantly increased bearing current caused by the transition from Si devices to WBG devices, advanced modeling and analysis approach was proposed by using coupled field-circuit electromagnetic finite element analysis (FEA) to model bearing voltage and current in electric machines, which took into account the influence of distributed winding conductors and frequency-dependent winding RL parameters. Possible bearing current issues in axial-flux machines, and possibilities of computation time reduction, were also discussed. Two experimental validation approaches were proposed: the time-domain analysis approach to accurately capture the time transient, the stationary testing approach to measure bearing capacitance without complex control development or loading condition limitations. In addition, two types of motors were employed for experimental validation: an inside-out N-type PMSM was used for rotating testing and stationary testing, and an N-type BLDC was used for stationary testing. Possible solutions for the increased CMV and bearing currents caused by the implementation of WGB devices were discussed and developed in simulation validation, including multi-carrier SPWM modulation and H-8 converter topology., �� 2021 Yibin Zhang

Additional file 1: Figure S1. Spinal cord transverse diameters. Figure S2. Immunogenicity of spinal cord was equivalent between DodgeTM and formalin fixation. Figure S3. Imaging and quantification workflow. Figure S4. Patterning of neither extravascular hemoglobin nor motor neuron pathology were affected by site of ALS onset; pTDP-43 inclusion load predicted motor neuron loss only in cervical cord of upper-limb onset cases. Figure S5. Extravascular hemoglobin did not correlate with motor neuron pathology, disease, or spinal cord tissue collection delay. Table S1. Review of blood-brain and blood-spinal cord barrier disruption in human ALS studies.

The gold-coated photoresist grating (GCPG) compressor is a core module of the high-repetition-rate superintense ultrafast lasers. Understanding how pulse trains with different repetition rates lead to laser-induced damage of GCPG is critical for future high-power laser applications. In this paper, we present the results of a multi-pulse laser-induced damage threshold (LIDT) investigation of GCPGs at different high repetition rates for the first time. The upper and lower endurance limits of S-on-1 beam-normal LIDT at 50–1000 Hz (800 nm, 35 fs) are ∼0.40 J/cm2 and 0.01 J/cm2, respectively, and the multi-pulse LIDT at 100 kHz is ∼0.02 J/cm2 corresponding to the peak intensity ∼64 GW/cm2 (1030 nm, 320 fs). The typical damage morphologies at 50–1000 Hz that the gold coating strips from the photoresist grating mask differ from those initiated from the expansion of the mask at 100 kHz. Focused ion beam scanning electron microscopy measurements show that the corners and small adhesion strength of interfaces are structural weaknesses. Moreover, theoretical modeling indicates that the differences mainly arise from pyrolysis and low heat-conduction of the mask. Overall, these results are highly practical and lay the foundation for the safe construction of high-repetition-rate ultra-high-power lasers based on the GCPG compressor.

This paper presents a sub-wavelength moth-eye-like antireflective structure on lithium triborate (LiB3O5, LBO) surface that can effectively promote the transmittance and maintain high laser-induced damage threshold (LIDT). Fabricated by holographic lithography and reactive ion-beam etching techniques, sub-wavelength periodic arrays can be obtained on the crystal surface. The surface morphology and transmittance were measured with atomic force microscope and spectrophotometer respectively. Single-sided transmittance of the LBO with moth-eye-like structure was confirmed to exceed 98% in the wavelength range of 1028–1300 nm, while is 98.73% at 1064 nm. For 1064 nm laser with the pulse width of 12 ns, the measured 1-on-1 LIDT is 42.57 J/cm2, which is about 2.28 times that of LBO compared with traditional antireflection (AR) coatings.

Let $\Omega$ be a bounded domain in $\mathbb{R}^2$ with smooth boundary, we study the following anisotropic elliptic Neumann problem with Hardy-H\'{e}non weight $$ \begin{cases} -\nabla(a(x)\nabla u)+a(x)u=a(x)|x-q|^{2\alpha}u^p,\,\,\,\, u>0\,\,\,\,\, \textrm{in}\,\,\,\,\, \Omega,\\[2mm] \frac{\partial u}{\partial\nu}=0\,\, \qquad\quad\qquad\qquad\qquad \qquad\qquad\qquad\qquad \,\ \ \,\,\,\, \textrm{on}\,\,\, \partial\Omega, \end{cases} $$ where $\nu$ denotes the outer unit normal vector to $\partial\Omega$, $q\in\overline{\Omega}$, $\alpha\in(-1,+\infty)\setminus\mathbb{N}$, $p>1$ is a large exponent and $a(x)$ is a positive smooth function. We investigate the effect of the interaction between anisotropic coefficient $a(x)$ and singular source $q$ on the existence of concentrating solutions. We show that if $q\in\Omega$ is a strict local maximum point of $a(x)$, there exists a family of positive solutions with arbitrarily many interior spikes accumulating to $q$; while if $q\in\partial\Omega$ is a strict local maximum point of $a(x)$ and satisfies $\langle\nabla a(q),\,\nu(q)\rangle=0$, such a problem has a family of positive solutions with arbitrarily many mixed interior and boundary spikes accumulating to $q$. In particular, we find that concentration at singular source $q$ is always possible whether $q\in\overline{\Omega}$ is an isolated local maximum point of $a(x)$ or not., Comment: This manuscript has been accepted for publication in Topological Methods in Nonlinear Analysis(TMNA). arXiv admin note: text overlap with arXiv:1904.02936

This work aims to design and fabricate sub-wavelength structures on lithium triborate surface for increasing its transmittance at 1064 nm. The finite-difference time-domain (FDTD) method is used to discuss the effects of subwavelength structure parameters such as period, depth, duty cycle and shape factor on the reflectivity. The subwavelength surface microstructures are fabricated by interference lithography technique and reactive ion beam etching method. The transmittance of the lithium triborate with single-side sub-wavelength structures is measured by UVvisible- near-infrared spectrophotometer. The results show that the transmittance of the sample with single-side microstructures at 1064 nm is about 4% higher than that of the polished substrate.

In a previous study, the temperature-rise of a spectral beam combining grating was analyzed theoretically and experimentally. It was concluded that the temperature of a grating can be effectively reduced by increasing the substrate thickness or by using a substrate material with higher thermal conductivity. In this study, yttrium aluminum garnet (YAG) was used as the substrate material to fabricate a spectral beam combining grating. The temperature, distortion, and far-field beam quality of the YAG-substrate-grating were analyzed theoretically and experimentally. It is concluded that, compared with the traditional quartz-substrate-grating, not only can the YAG-substrate-MDG withstand higher power, but the beam quality of the diffraction laser is also better.

In this work, a chirped volume Bragg grating (CVBG) with over 40 nm high efficiency broadband spectra for pulse compression of near 100 fs was studied. Based on the fundamental matrix method, the effects of various structural parameters of CVBG on its diffraction characteristics were analyzed and then a design of broadband and high efficiency CVBG was proposed. Afterward, the monolithic CVBG was utilized to stretch and recompress a 100 fs pulse with a center wavelength of 1030 nm. The result shows this device has a high diffraction efficiency (84%) and a fine reciprocity. For the fabrication of large-size broadband CVBGs, double cylindrical wave holographic interference in photo-thermorefractive (PTR) glass was applied to achieve a wide range uniform and stable light field, which could greatly minimize unnecessary space chirp.

With increased power of spectral beam combination, surface heat distortion of multilayer dielectric gratings (MDGs) could occur. In this study, the damage morphology of MDGs was initially analyzed under a continuous-wave laser irradiation. Subsequently, the surface distortion and temperature rise of different MDGs were tested experimentally. The experimental results showed that the initial damage of MDGs was caused by the thermal stress. Further, the thermal stress of the multilayer dielectric films on the MDG surface was analyzed theoretically. The calculated results were in good agreement with the experimental results. The conclusions indicated that with the increase of the MDG surface temperature, the stress in the HfO2 layers initially reached the stress damage threshold of the dielectric films and, therefore, the damage occurred.

This report is focused on laser induced damages and mechanisms of different pulse compression gratings(PCG) including multilayer dielectric gratings, metal gratings and metal-multilayer dielectric gratings. And the potential of metal-multilayer dielectric gratings is analysed.

A new 800nm center-wavelength metal dielectric grating with all SiO2 grating structures is designed and tested, which has a high laser damage threshold of 0.40J/cm2 on grating surface at pulse duration of 32fs.

Let $\Omega$ be a bounded domain in $\mathbb{R}^2$ with smooth boundary, we study the following elliptic Dirichlet problem $$ \begin{cases} -\Delta\upsilon= e^{\upsilon}-s\phi_1-4\pi\alpha\delta_p-h(x)\,\,\,\, \,\textrm{in}\,\,\,\,\,\Omega,\\[2mm] \upsilon=0 \quad\quad\quad\quad\quad\quad \qquad\qquad\quad\quad\,\,\,\, \textrm{on}\,\ \,\partial\Omega, \end{cases} $$ where $s>0$ is a large parameter, $h\in C^{0,\gamma}(\overline{\Omega})$, $p\in\Omega$, $\alpha\in(-1,+\infty)\setminus\mathbb{N}$, $\delta_p$ denotes the Dirac measure supported at point $p$ and $\phi_1$ is a positive first eigenfunction of the problem $-\Delta\phi=\lambda\phi$ under Dirichlet boundary condition in $\Omega$. If $p$ is a strict local maximum point of $\phi_1$, we show that such a problem has a family of solutions $\upsilon_s$ with arbitrary $m$ bubbles accumulating to $p$, and the quantity $\int_{\Omega}e^{\upsilon_s}\rightarrow8\pi(m+1+\alpha)\phi_1(p)$ as $s\rightarrow+\infty$., Comment: This manuscript has been accepted for publication in Advances in Differential Equations

In a spectral beam combination system, temperature increase of the multilayer dielectric grating (MDG) worsens the far-field beam quality of the output laser. To accurately monitor the surface temperature of the MDG, this study deposits V O 2 phase-change film on the lowest layer of multilayer dielectric films in the MDG and tests the transmittance with a probe laser. Based on this measurement, the surface temperature of the MDG can be calculated. Additionally, the study analyzes the influence of V O 2 film on the surface electric field and the − 1 diffraction efficiency of the MDG and presents a specific example of using V O 2 film to test high reflector temperature. The study concludes that V O 2 film is a feasible method of measuring temperature and better than an infrared thermal imager.

Spectral beam combination is a promising method for high-radiance lasers with a good beam quality. With the increase of the combination power, the temperature of the multilayer dielectric grating (MDG) unavoidably increases, leading to surface heat distortion of the MDG. In this study, the temperature field equation of the MDG is derived, and the key factors influencing the MDG temperature are investigated. Furthermore, experiments are performed to confirm the calculation results. The results reveal that the increase of the thickness of the substrate can improve the power tolerance of the MDG but delays the stable output of beam laser; use of a substrate material with a large thermal conductivity can greatly reduce the temperature of the MDG.

Two cleaning methods for multilayer dielectric pulse compression gratings (MDG) were studied. The first method is SPM (Sulfuric-Peroxide Mixtures, 98wt%H2SO4+30wt%H2O2) + megasonic, and the second method is Oxygen plasma + HPM (Hydrochloric/Peroxide Mixture, 37wt%HCl+30wt%H2O2+DIH2O) + megasonic. To compare the cleaning effectiveness, the element content of sample surface, diffraction efficiency, surface roughness, temperature rising and laser damage induced threshold (LIDT) were measured. The 1-on-1 LIDT of samples cleaned by the first and the second methods are 7.55 and 5.32 J/cm(2) respectively, with 1064 nm laser pulse (12 ns, s-polarized) at incidence angle of 70 degrees. In addition, the sample cleaned by the second method has lower surface contamination content, but the sample cleaned by the first method has better performance in diffraction efficiency, surface roughness and temperature rising. By further analyzing, we find that element Fe brought by oxygen plasma cleaning process in the second method is the factor that affects the damage performance and temperature rising. Therefore, the cleaning method based on the first one, the SPM + megasonic is better for improving the laser damage performance of MDG.

In this study, the realization of multiplexed volume Bragg gratings (VBGs) working as angle amplifiers in high power beam scanning system is theoretically and experimentally investigated. The design of the multiplexed VBG for the working wavelength of 1064 nm is described. We propose a cascaded multiplexed VBGs scheme that consists of 12 grating channels. Three 4-channel multiplexed VBGs were fabricated inside photo-thermo-refractive (PTR) glasses by multiple exposures and subsequent heat treatment. The test results show that this angle amplifier can achieve discrete angle deflection ranging from -45° to + 45°. The relative diffraction efficiency of all the grating channels is more than 80% and is almost polarization independent.

In previous research, the thermal distortion and far-field beam quality of a spectral beam combining grating were analyzed by theory and experiment under the irradiation of a high-power continuous-wave laser. It was concluded that the thermal expansion of the substrate was the main cause of the grating distortion and decrease in the beam quality. However, there was no further study to determine a method to decrease the heat deposition on the grating surface and far-field beam quality factor, M2. In this paper, we theoretically simulate the influence of the substrate thickness on the temperature field distribution and far-field beam quality of a multilayer dielectric grating. An experimental setup is proposed to verify the theoretical calculations. The experimental results are in good agreement with the calculations. The conclusions indicate that the temperature rise of the grating and M2 are effectively reduced by increasing the thickness of the substrate.

In this paper, we present a method for achieving precise evaluation of amplitude of refractive index modulation (RIM) inside the volume Bragg grating (VBG) recorded in photo-thermo-refractive (PTR) glasses. The Gaussian divergence characteristics of the incident beam is theoretically considered when calculating the angular selectivity of VBG, and the profiles of experimental angular selectivity curves are utilized to determine the value of RIM with one step. The effectiveness of our proposed method is experimentally verified. This method is applicable even if the full width at half maximum (FWHM) of VBG's angular selectivity curve has the same order of magnitude as or is less than the beam divergence.

Rational planning and improvement on the operational efficiency of the logistics park depends on the precise of definition of the radiation scope of the logistics park, but there is still a lack of scientific and accurate theoretical method aiming at solving the definition of the radiation scope of the logistics park. Based on the traditional space division model such as potential model in the economic geography as well as giving full consideration to the important role the transport network playing in the logistics activities, the accessibility was introduced into the traditional potential model based on the Euclidean distance metric to modify the distance parameter, and the method of defining the radiation scope of logistics park based on applying the accessibility analysis to potential model was proposed. Finally, on the basis of GIS software, this method was used to define the radiation scope of the five logistics parks of the similar type in Sichuan province. It proved that the application of this method based on GIS software had the advantages of the scientific accuracy as well as the easy acquisition and operation of data, which reflected the higher application value.

An opcode behavior based method is proposed to detect malware. Opcode behaviors are represented as opcode sequences from a decompiled executable. To accurately describe the malware behaviors, we construct the opcode running tree to simulate the dynamic execution of a program, and opcode n-grams are extracted to represent the features of an executable. The experimental results show that the opcode behaviors extracted by this method can fully represent the behavior characteristics of an executable. Compared with the detection method based the opcode distributions, the proposed method has higher overall accuracy and a lower false positive rate.

A multiresidue method is described for the analysis of 106 multiclass pesticides (organochlorine, organophosphate, carbamate, pyrethroid, and triazine classes) in apple juice in a single injection. The determination procedure was based on matrix solid-phase dispersion of juice on diatomaceous earth in a glass column and subsequent extraction with a mixture of hexane–dichloromethane (1 + 1) at a flow rate of 5 mL/min. The analytes were determined by capillary gas chromatography with mass spectrometric detection and confirmed by their retention times and ion ratios. The coefficients of variation for analysis of samples fortified over the range of 0.01–0.2 mg/kg were 1.62 to 18.4%, and the recoveries for all analytes were between 70 and 110%.

Transmission lines, microstrip and coplanar waveguide, have been fabricated on lossy silicon substrates embedded in CMOS Cu/SiO2 interconnect layers. The characteristic impedance, the loss and the slowing factor have been studied in detail with the geometric size of transmission lines. It is shown that microstrips and coplanar waveguides embedded in silicon oxide can be achieved with CMOS compatible interconnect technology and with low loss on lossy silicon wafers, which provide the essential passive components for designing microwave and millimetre-wave circuits on silicon wafers.

Thick copper (Cu)/Black Diamond™ (BD) layer up to 4 μm has successfully been integrated in CMOS interconnect process to improve the quality of on-chip RF passive components. It is shown that BD film is easy to crack when its thickness is up to 4 μm. However, by inserting one or few layers of dielectric material, BloK™, the stress in the entire dielectric film stack can be reduced. Although the reduction of the tensile stress of the stack is insignificant, the inserted BloK™ layer effectively prevents cracking from happening in the film stack. Spiral inductors have been integrated in developed Cu/BD (4 μm) top-metal-layer. Both Q value and resonate frequency of developed inductors are improved comparing to the inductors fabricated in previous top-metal-layer with 1 μm Cu/SiO 2 stack.

The energy band structure, minority carrier concentration, and charge distribution of metal-insulator-semiconductor inversion layer (MIS/IL) Si solar cells have been calculated using Fermi-Dirac statistics. The variation of the cell's sheet resistance with the fixed positive charge and interface state density have been analyzed. The theoretical results tally well with the experiment results.

Iron (Fe) deficiency in humans caused by inadequate dietary intake is a global nutritional problem. A glass house pot experiment was conducted to evaluate the effect of foliar FeSO₄ containing applications on concentrations of Fe, Zn, and Fe bioavailability in polished rice among five rice cultivars. The results showed that foliar application of FeSO₄, FeSO₄, plus nicotianamine (NA), and FeSO₄ plus NA with ZnSO₄ increased the grain Fe concentration by 16.97%, 29.9%, and 27.08%, respectively. The grain Fe bioavailability also increased by foliar application of FeSO₄, FeSO₄ plus NA, and FeSO₄ plus NA with ZnSO₄; these represent increases of 12.63%, 20.86%, and 18.75%, respectively. Foliar FeSO₄ containing applications improved the Fe bioavailability and might be attributed to the reduction of phytic acid and the increase of Fe concentration in polished rice. Addition of ZnSO₄ to foliar Fe application increased both Fe and Zn content without altering Fe content and bioavailability. In addition, the cultivar difference in Fe and Zn concentration was observed and may be due to the genetic control of leaf absorption and seed deposition of foliar application. Furthermore, the cultivar difference in Fe bioavailability observed might be attributed to the variation of grain Fe, phytic acid, and total phenolics contents among the five rice cultivars. The results suggested that foliar FeSO₄ containing applications represent a promising agricultural approach to reduce Fe deficiency in countries where polished rice is extensively consumed.