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In this study, the traditional solid-phase method was used to synthesize CoMgxFe(2−x)O4 (x = 0–0.1) ceramic, and the effect of replacing Fe3+ with Mg2+ on the structure, crystal phase, and magnetic properties of ceramic crystals was analyzed by X-ray diffraction, scanning electron microscopy, Raman spectroscopy, and vibrating sample magnetometer. Results showed that the lattice constant decreased as Mg2+ content increased. When x 0.05, Mg2+ affected the tetrahedral position and the octahedral position. The substitution of nonmagnetic Mg2+ for magnetic Fe3+ weakened the A-O-B effect of CoFe2O4 and lowered the magnetocrystalline anisotropy constant as well as the magnetostriction coefficient, which led to an enhancement on the strain sensitivity of CoMgxFe(2−x)O4 in a low magnetic field, and a maximum value of 4.6 × 10−9 A−1 m was obtained as x = 0.075.

Rail ineffective transport refers to meaningless and unvalued transportation in the rail freight system, which including convective transportation, roundabout transportation, and unprocessed transportation. Ineffective transport does not only result in a strain on transportation capacity and increase costs but also imposes significant external pollution on low-carbon development. This paper attempts to study ineffective transport among rail stations. Base on defining the concept of ineffective transportation, it analyzes the ineffective transport volume and ineffective transport propagation on each station, which helps to seek more efficiently the core ineffective transport stations in the rail freight network. To better understand the mechanism of ineffective transport propagation effect at the rail freight transport system-level, an ineffective transport causality network (ITCN) was built based on the Granger causality test. Through the topology model of ineffective transport at 50 stations in China from 2013 to 2016, the results show that the ineffective transport of each station affects approximately 12 stations and also affected by 12 stations on average. Large-sized stations are affected by more stations than downstream. Small-sized and medium-sized stations are opposed. There are four core stations in this ITCN, and optimization of the ineffective transport at these four stations will save nearly fifty million kilogram of transport volume per year.

Because of good thermal, electrical, and mechanical properties, low-temperature cofired ceramic (LTCC) has shown great potential in microelectronic applications. One of the most promising directions of LTCC technology development are integrating and packing sensors. In this article, a wireless passive capacitive pressure sensor operating in the MHz range based on cofiring of heterogeneous materials with LTCC technology is proposed, and the design, simulation, and fabrication of the sensor are demonstrated and discussed. It consists of a circular spiral inductor and a capacitor of two electrodes separated by a glass medium. Furthermore, a unique process of cofiring of heterogeneous materials was introduced to avoid deformation of the capacitive embedded cavity during lamination or sintering. The results show that the inductance of the inductor and the capacitance of the capacitor embedded in the sensor are .28 μH and 16.80 pF, respectively. The novel sensor has a sensitivity of approximately 847 Hz/MPa within the pressure range from atmospheric pressure to 100 MPa.

A reconfigurable full-metal-rimmed MIMO antenna is designed and proposed for WWAN/LTE smartphones. This antenna consists of two centro-symmetrically distributed antenna elements and radiation structures using the unbroken metal rim in plastic casing. It can achieve a good isolation of more than 17dB over the entire operation bands. Each antenna element occupies a small ground area of 30 × 6 mm2. The U-shaped feeding line provides a coupled feed and the antenna element generates four typical loop resonant modes. Using reconfigurable technique to combine these four resonant modes, this hepta-band MIMO antenna can satisfactory cover lower bands of GSM850/900 and higher bands of GSM1800/1900/ UMTS/LTE2300/2500. A prototype MIMO antenna was fabricated and the measured results of S-parameters, antenna efficiency and gain, envelope correlation coefficient, mean effective gain, and channel capacity are reported.

Using the finite difference time domain method, the electromagnetic field distribution of terahertz waves are simulated in photonic band gap structures with different single-defect, line-shaped defects and L-type defects composed of three single-defects. Introducing the photonic band gap structure with difference coordinates single-defects, the resonance frequency and amplitude of the single-defect along the vertical direction of line-shaped defects waveguide have more sensitive than the parallel direction. Introducing the photonic band gap structure with line-shaped defects composed of three defects, the resonant in the endpoint of line-shaped defects have high amplitude and in the middle of line-shaped defects have two resonant frequencies. Introducing the photonic band gap structure with L-type defects composed of three defects, three high-Q resonant frequencies appeared simultaneously in the some monitor coordinates.

Using Co2O3 as the Co source, doped cerium oxide thin films with the composition of Ce0.97Co0.03O2−δ (CCO) are deposited on Si(111) and glass substrates by pulse laser deposition technique. X-ray diffraction reveals that CCO films with (111) preferential orientation are grown on Si, while the film on glass is polycrystalline with nanocrystal. X-ray photoelectron spectroscopy shows that the Co displaces the Ce atom and exists in high spin state rather than low spin state, which contributes to the room-temperature ferromagnetism confirmed by vibration sample magnetometer. Films on Si and glass are different in ferromagnetism, which is believed to be induced by different film microstructures. Based on these results, the possible ferromagnetism in this insulating film is discussed. Anyway, successful fabrication of CCO films with room-temperature ferromagnetism on Si substrates is of great importance in both technological and theoretical aspects.

In the age of cyber-economy, the human resource management (HRM) of E-business enterprises presents lots of electronic characteristics and has better advantages comparing with traditional HRM. In the Human Resource Selection strategies of E-business enterprises, the background of e- business should be taken into account and particular emphasis should be put on talents selecting, training, using and keeping.

This paper defines the concept of E-interview, analyze the advantage of E-interview and elaborate the reason of the application scope of the E-interview in the current personnel selection. This paper not only points out the important position and the applicable scope of the E-interview in the current personnel select, but also does the basic estimate to the application foreground of the E-interview. For making good use of E-interview in the business and government, it also gives some suggestions about the preparation of the hardware and applicants

This paper defines the concept of E-interview, analyze the advantage of E-interview and elaborate the reason of the application scope of the E-interview in the current personnel selection. This paper not only points out the important position and the applicable scope of the E-interview in the current personnel select, but also does the basic estimate to the application foreground of the E-interview. For making good use of E-interview in the business and government, it also gives some suggestions about the preparation of the hardware and applicants.

This paper defines the concept of E-interview, analyze the advantage of E-interview and elaborate the reason of the application scope of the E-interview in the current personnel selection. This paper not only points out the important position and the applicable scope of the E-interview in the current personnel select, but also does the basic estimate to the application foreground of the E-interview. For making good use of E-interview in the business and government, it also gives some suggestions about the preparation of the hardware and applicants.

We have successfully fabricated polymer/organic heterostructure doped light-emitting diodes with high stability and efficiency using a novel poly-TPD (PTPD) as hole transport material and the high fluorescent Rubrene as dopant. The basic structure of the heterostructure is PTPD/Alq/sub 3/. The device was doped in the single layer and double layer. The structure of energy bands for the doping device was given. Initial voltage, initial luminance, luminance efficiency, EL quantum efficiency and operational stability under constant current driving as well as turn-on voltage were measured. With the doping of double layers, the EL quantum efficiencies are about 2 times greater than that of the undoped device but the turn-on voltage is increased. Comparing the doped device with the undoped device and conventional TPD/Alq/sub 3/ diode, it is found that (a) the durability of the devices with PTPD as HTL is higher than that of the referenced device with TPD as HTL, and (b) the stability of the doped devices is significantly higher than that of the undoped device and the lifetime for the device of doped double layers is the longest.

In this paper we present a novel dual-band metamaterial absorber (MA), which is composed of a periodically arranged 2nd order Koch curve array and a metal ground separated by a dielectric spacer. By employing the fractal characteristic of space-filling, more compact unit cell with a size reduction of 17.5% has been achieved as compared with the conventional square-shaped MA. The dual-band operation is not originated from the hybrid or stacked methods as reported before, but from the two distinct resonance modes of the 2nd order Koch curves induced by the incident electromagnetic wave, and can be realized within a single unit cell. Due to its rotationally symmetric pattern, the absorptivity of the above presented MA is insensitive to the polarization of the incident waves and can perform well in a wide range of incident angles. The effective medium theory has been employed to investigate the underlying physical mechanism of the fractal MA, and good agreements between simulation and experimental results have been achieved.

Magnetic properties of La doped M-type barium ferrites are studied. The samples are prepared by the standard solid state reaction method. The influences of La3+ on structures and magnetic properties of barium ferrites (Ba1-xLaxFe12O19) are investigated. Single-phase M-type barium ferrites with chemical composition of Ba1-xLaxFe12O19 (x=0.0—0.6) are formed by sintering at 1100—1175 ℃ in air. Scanning electron microscopy (SEM) reveals that the La doping has no effect on the structure of barium ferrite. Vibrating sample magnetometer (VSM) shows that with the valaue of x increasing, the saturation magnetization (Ms) increases, reaching a maximum at x=0.2 and then decreases and the coercivity of the sample increases continuously. The value of Ms reaches a maximum value of 62.8 emu/g at x=0.2 and 1175 ℃, and the Hc reaches a maximum value of 3911.5 Oe at x=0.6 and 1125℃.