Equivalent Circuit Analysis of an RF Integrated Inductor with Ferrite Thin-Film

An equivalent circuit for a novel RF integrated inductor with ferrite thin-film is derived. The enhancement of the magnetic ferrite thin-film on the inductance （L） and quality factor （Q） of the inductor is analyzed. Circuit element parameters are extracted from RF measurements. Compared with the reference air-core inductor without magnetic film, L and Q of the ferrite thin-film inductor are 17% and 40% higher at 2GHz,respectively. Both the equivalent circuit analysis and test results demonstrate significant enhancement of the performance of RF integration inductors by ferrite thin-film integration.

运城市举办农村会计帐簿大赛

农村财务管理是当前人们普遍关心的热点问题。怎样通过规范帐簿、票据、记帐方法和结算手续等,以堵塞漏洞、减少失误,不断提高农村财务管理水平和财会人员素质,更好地适应农村经济发展的需要?山西省运城市举办农村会计帐簿大赛,为我们提供了很好的经验。

我对“全员风险抵押承包”的看法

近几年,由于企业流动资金严重不足,“全员风险抵押承包”应运而生。“全员风险抵押承包”的宗旨是把承包者和职工的切身利益与企业的命运捆在一起,使企业的每个职工都感到有压力,以体现“利益均沾、风险共担”的原则。目的是从职工中筹集资金,以缓解企业流动资金不足之困难。其实,这种想法和作法本身就是不合理的。实践证明,“全员风险抵押承包”弊多利少,下面。

Characterization and Reliability of Thin Film Resistors for MMICs Application Based on AlGaN/GaN HEMTs

Tantalum nitride （TAN） and nichrome （NiCr） are the two most common materials used as thin film resistors （TFR） for monolithic microwave integrated circuits （MMIC） based on AlGaN/GaN high electron mobility transistors （HEMTs）. In this study,we compare the reliability of the two materials used as TFRs on a semi-insulation 4H SiC substrate. Through the comparison between NiCr and TaN thin-film resistor materials, we find the square resistor （Rs） of TaN TFR increases as the annealing temperature increases. However, the R s of NiCr TFR shows the opposite trend. We also find the change of the TaN Rs and contacted resistor （Re） is smaller than the NiCr. After O2 plasma exposure in RIE,the TaN R s only decreases 0.7Ω,or about 2.56%, and R c increases 0.1Ω,or about 6.6%, at an annealing temperature of 400℃. In contrast, the NiCr R s and R c show large changes at different annealing temperatures after O2 plasma exposure. In conclusion,TaN is more stable during plasma exposure after 400℃ annealing in N2 ambient.

Fabrication of LaAlO3 film by sol-gel process with corresponding inorganic

Well-cubic perovskite lanthanum aluminate (LaAlO3) film on (110) silicon substrate was fabricated by sol-gel method with corresponding inorganic salts. Lanthanum acetate and aluminum acetate glacial acetic acid solutions were prepared via ligand exchange starting from lanthanum nitrate hexahydrate and aluminum nitrate hexahydrate after being refluxed. (CH3CO)2O removed nitrates and the crystallized H2O completely, acetylacetone (AcAc) was partially bidentated with metallic ion of the metallic acetates and formed La(OAc)3 (AcAc)x, which were hydrolyzed into La(AcAc)3 (OH)x by ?x ?x adding 10 ml 0.4% methyl cellulose (MCL) solution. The La(AcAc)3 (OH)x, polymerizing and combining with MCL, ?x formed the LaAlO3 sol precursor with heteropolymeric structure and formed film easily. The epitaxial LaAlO3 film on Si(110) substrate was crystallized after being annealed in thermal annealing furnace for 650?750 °C/30 min. The mor- phologies and microstructures were characterized. The refractive index of the LAO film was 1.942 to 2.007; the dielectric constant and the dissipation factors were estimated to be 23?26 and 2.1×10?4 ? 2.4×10?4 respectively.

Study on Factors Affecting Springback and Application of Data Mining in Springback Analysis

Springback of sheet metal induced by elastic recovery is one of major defects in sheet metal forming processed. Springback is influenced by many factors including properties of the sheet material and processing conditions. In this paper, a springback simulation was conducted and comparisons between the results based on different processing variables were illustrated. The discovery of knowledge of the effects of geometry and process parameters on springback from FEM results becomes increasingly important, as the number of numerical simulation has grown exponentially. Data mining is an effective tool to realize knowledge discovery in simulation results. A data-mining algorithm, rough sets theory (RST), was applied to analyze the effects of process parameters on springback in U-bending.

From cluster assembly to ultrathin nanocrystals and complex nanostructures

Ultrathin nanostructures have attracted much attention in recent years due to their predictable novel properties and various potential applications. The improvement in synthetic skills has led to many successful syntheses of nanostructures including zerodimensional (0D) nanoclusters, one-dimensional (1D) nanowires, two-dimensional (2D) nanosheets and other higher-level complex nanostructures, where cluster-assembly of primary nanocrystals is a common process. In this review, progress in ultrathin nanocrystals in the last decade and several important factors in the growth mechanisms are covered. By giving examples of cluster assembly from 1D to 3D nanostructures, the utility of cluster assembly in the synthesis of new materials has been demonstrated.

Mechanics of flexible and stretchable piezoelectrics for energy harvesting

As rapid development in wearable/implantable electronic devices benefit human life in daily health monitoring and disease treatment medically, all kinds of flexible and/or stretchable electronic devices are booming, together with which is the demanding of energy supply with similar mechanical property. Due to its ability in converting mechanical energy lying in human body into electric energy, energy harvesters based on piezoelectric materials are promising for applications in wearable/implantable device's energy supply in a renewable, clean and life-long way. Here the mechanics of traditional piezoelectrics in energy harvesting is reviewed, including why piezoelectricity is the choice for minor energy harvesting to power the implantable/wearable electronics and how. Different kinds of up to date flexible piezoelectric devices for energy harvesting are introduced, such as nanogenerators based on Zn O and thin and conformal energy harvester based on PZT. A detailed theoretical model of the flexible thin film energy harvester based on PZT nanoribbons is summarized, together with the in vivo demonstration of energy harvesting by integrating it with swine heart. Then the initial researches on stretchable energy harvesters based on piezoelectric material in wavy or serpentine configuration are introduced as well.

Progress in flexible organic thin-film transistors and integrated circuits

Organic thin-film transistor constructs the headstone of flexible electronic world such as conformable sensor arrays and flexible active-matrix displays. With solutionprocessed methods, it forges ahead toward large-area, lowcost manufacturing goals. As an indispensable complement to traditional silicon-based transistors, organic thin-film field-effect transistors have made great progress in materials,performance, bending capacity, and integrated circuits in recent few years. Flexible transistors and circuitry have extremely promising application prospects and possess irreplaceable status in foldable displays, artificial skins and bendable smart cards. In this review, we will discuss the evolution of flexible organic transistors and integrated circuits in terms of material, fabrication as well as application.

Inverted polymer solar cells with a solution-processed zinc oxide thin film as an electron collection layer

A solution-processed zinc oxide (ZnO) thin film as an electron collection layer for polymer solar cells (PSCs) with an inverted device structure was investigated. Power conversion efficiencies (PCEs) of PSCs made with a blend of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM) are 3.50% and 1.21% for PSCs with and without the ZnO thin film, respectively. Light intensity dependence of the photocurrent and the capacitance-voltage measurement demonstrate that the increased PCEs are due to the restriction of the strong bimolecular recombination in the interface when a thin ZnO layer is inserted between the polymer active layer and the ITO electrode. These results demonstrate that the ZnO thin film plays an important role in the performance of PSCs with an inverted device structure.

Interactive image segmentation with a regression based ensemble learning paradigm

To achieve fine segmentation of complex natural images, people often resort to an interactive segmentation paradigm, since fully automatic methods often fail to obtain a result consistent with the ground truth. However, when the foreground and background share some similar areas in color, the fine segmentation result of conventional interactive methods usually relies on the increase o f manual labels. This paper presents a novel interactive image segmentation method via a regression-based ensemble model with semi-supervised learning. The task is formulated as a non-linear problem integrating two complementary spline regressors and strengthening the robustness of each regressor via semi-supervised learning. First, two spline regressors with a complementary nature are constructed based on multivariate adaptive regression splines （MARS） and smooth thin plate spline regression （TPSR）. Then, a regressor boosting method based on a clustering hypothesis and semi-supervised learning is proposed to assist the training of MARS and TPSR by using the region segmentation information contained in unlabeled pixels. Next, a support vector regression （SVR） based decision fusion model is adopted to integrate the results of MARS and TPSR. Finally, the GraphCut is introduced and combined with the SVR ensemble results to achieve image segmentation. Extensive experimental results on benchmark datasets of BSDS500 and Pascal VOC have demonstrated the effectiveness of our method, and the com- parison with experiment results has validated that the proposed method is comparable with the state-of-the-art methods for in- teractive natural image segmentation.

Model for increased efficiency of CIGS solar cells by a stepped distribution of carrier density and Ga in the absorber layer

In this paper, several structures for multilayer Cu(In1-xGax) Se2 (CIGS) thin film solar cells are proposed to achieve high conversion efficiency. All of the modeling and simulations were based on the actual data of experimentally produced CIGS cells reported in the literature. In standard CIGS cells with a single absorber layer, the effects of acceptor density and Ga content on device performance were studied, and then optimized for maximum conversion efficiency. The same procedure was performed for cells with two and three sectioned CIGS absorber layers in which Cu and/or Ga contents were varied within each consecutive section. This produces an internal additional electric field within the absorber layer, which resulted in an increase in carrier collection for longer wavelength photons, and hence, improvement in the conversion efficiency of the cell. An increase of approximately 3% in efficiency is predicted for cells with two layer absorbers. For multilayer cells in which Cu and Ga distribution were stepped simultaneously, the improvement could be approximately 3.5%. This improvement is due to; enhanced carrier collection for longer-wavelength photons, and reduced recombination at the heterojunction and back regions of the cell. These results are confirmed by the physics of the cells.

Highly uniform carbon nanotube nanomesh network transistors

A new type of single-walled carbon nanotube （SWNT） thin-film transistor （TFT） structure with a nanomesh network channel has been fabricated from a pre- separated semiconducting nanotube solution and simultaneously achieved both high uniformity and a high on/off ratio for application in large-scale integrated circuits. The nanomesh structure is prepared on a high-density SWNT network channel and enables a high on/off ratio while maintaining the excellent uniformity of the electrical properties of the SWNT TFTs. These effects are attributed to the effective elimination of metallic paths across the source/drain electrodes by forming the nanomesh structure in the high-density SWNT network channel. Therefore, our approach can serve as a critical foundation for future nanotube-based thin- film display electronics.