摘要：A digital predistorted class-F power amplifier （PA） using Cree GaN HEMT CGH40010 operating at 2. 12 GHz is presented to obtain high efficiency and excellent linearity for wideband code-division multiple access （ WCDMA ） applications. Measurement results with the continuous wave （CW） signals indicate that the designed class-F PA achieves a peak power-added efficiency （PAE） of 75. 2% with an output power of 39.4 dBm. The adjacent channel power ratio （ACPR） of the designed PA after digital predistortion （DPD） decreases from -28. 3 and -27. 5 dBc to -51.9 and -54. 0 dBc, respectively, for a 4-carrier 20 MHz WCDMA signal with 7. 1 dB peak to average power ratio （PAPR）. The drain efficiency （DE） of the PA is 37. 8% at an average output power of 33. 3 dBm. The designed power amplifier can be aoolied in the WCDMA system.

摘要：In order to investigate the sand mold strength after the aeration sand filling-high pressure squeeze moldingprocess,a tree-dimentional(3D)numerical simulation was *** commercial finite element method(FEM)software ABAQUScombined with a revised Drucker-Prager/Cap model was used to simulate the squeeze compaction ***,the sand bulk density after the aeration sand filling process was tested by a specially designed experiment,which divided the whole sand bulk in the molding chamber into5x9regions and it was used as the input to simulate the squeeze *** the simulation process,the uniform modeling simulation and the patition modeling simulation methods were used a d the3D numercal simulation results were compared with correlative benchmark *** the3D numerica simulation results,it can be concluded that the uniform sand bulk density distribution can obtain a high quality sandmold and the revised Drncker-Pager/Cap model is suitable for handling the situation with the complex ***3D numerical simulation results can predict well the sand mold strength distribution and can be used as guidelines for the production practice.

摘要：A series of carbamate-containing sialyltransferase inhibitors were designed and synthesized to simulate phosphate-linked *** inhibitory activities were assayed against recombinant human ST3Gal I and ST6Gal I by using the Schmidt’s HPLC-based *** synthetic compound 15 g showed moderate inhibitory *** findings implied that carbamate might serve as a bioisosteric replacement for a phosphate group in sialyltransferase inhibitor design to improve the membrane permeability.

摘要：A compact multi-throttle aerostatic guideway is the preferred structure for high precision and acceleration motion in the variable-slit system(VS)of *** presence of microstructure,such as recesses and grooves,on the guideway working surface has been found to improve the loading ***,the effects on the guideway performance of changing the microstructure on the micron level are not yet *** mesh adaptation method,which was proposed by the authors,is employed in this paper to quantitatively study the influences of four microstructure *** effect of tuning these parameters on the loading performance is *** level of impact determines the proposed design process of the *** characteristic feature of the proposed design process is that the working points of carrying capacity,stiffness,and rotational stiffness are unified under twoway adjusting by means of recess *** to the proposed design process and tuning method,the restriction of supply pressure is lifted to a certain extent and the mutual tradeoff among the loading performances is *** experimental results show that the rotational stiffness of the designed guideway,based on the tuned parameters,reached 2.14×10^(4) Nmrad1 and increased by 69.8%.In a scanning test of the applied VS on argon fluoride laser(ArF)photolithography,the average scanning acceleration reached 67.5 m·s^(-2),meeting the design specification.

摘要：This paper introduces a homemade injection-enhanced gate transistor （IEGT） with blocking voltage up to 3.7 kV. An advanced cell structure with dummy trench and a large cell pitch is adopted in the IEGT. The carrier concentration at the N-emitter side is increased by the larger cell pitch of the IEGT and it enhances the P-i-N effect within the device. The result shows that the IEGT has a remarkablely low on-state forward voltage drop （VCE（sat）） compared to traditional trench IGBT structures. However, too large cell pitch decreases the channel density of the trench IEGT and increases the voltage drop across the channel, finally it will increase the VCE（sat） of the IEGT. Therefore, the cell pitch selection is the key parameter consideration in the design of the IEGT. In this paper, a cell pitch selection method and the optimal value of 3.3 kV IEGT are presented by simulations and experimental results.

摘要：A three-dimensional diesel particulate filter(DPF)simulation model was developed by using AVL software FIRE to study the effects of four factors on soot particle distributions along the axial and radial directions in the DPF after the model accuracy was *** orthogonal test method was used to determine the importance and weights of the design of experiments(DoE)factors such as the expanding angle,the number of channels per square inch,and the exhaust mass flow *** effects of these factors on the uniformity of the soot particle distributions were also *** results show that when the soot loading time was 400 s,the soot particles inside the DPF along the axial direction exhibited a bowl shape,which was high on the both ends and low in the *** uniformity of the axial distribution of soot particles reduces significantly with an increase in the number of channels per square *** uniformity of the radial distribution reduced with an increase in the expanding angle of the divergent *** on the impacts on the axial uniformity,the three most influencing factors in a descending order are the number of channels per square inch,the exhaust mass flow rate,and the expanding angle of the divergent tube.

摘要：In order to satisfy the demands for diffractive telescopes in space exploration, a new deployable space diffractive tele- scope is designed. The structure and geometrical sizes of the spontaneously deployable telescope are preliminarily designated through the Serrurier truss principle and the optimized design theory. The finite element model of the de- ployable structure is established, and its deployed characteristics are analyzed. The prototype of the spontaneously de- ployable structure is constructed and some experiments are carried out to study its characteristics. Experimental results indicate that the deployable structure is 2.95 m in length, its repetitive deployed precision can reach less than 2 ram, the off-center error is less than 0.3 mm, and its deployed precision can be adjusted to micrometer level by actuators when it has deployed. It has simple structure, low mass, steady and reliable deployment, as well as higher precision for space diffractive telescopes.

摘要：It is generally acknowledged that mobile communication base stations are composed of hardware components such as Field Programming Gate Array （FPGA）, Digital Signal Processor （DSP）, which promise reliable and fluent services for the mobile users. However, with the increasing demand for energy-efficiency, approaches of low power-consumption and high-flexibility are needed urgently. In this circumstance, General Purpose Processor （GPP） attracts people＇s attention for its low-cost and flexibility. Benefited from the development of modern GPP in multi-core, Single Instruction Multiple Data （SIMD） instructions, larger cache, etc., GPPs are capable of performing high-density digital processing. In this paper, we compare several software-defined radio （SDR） prototypes and propose the general architecture of GPP-based soft base stations. Then, the schematic design of resource allocation and algorithm optimization in soft base station implementation are studied. As an application example, a prototype of GPP-based soft base station referring to the 3rd Generation Partnership project （3GPP） Long Term Evolution （LTE） is realized and evaluated. To the best of our knowledge, it is the first Soft-LTE prototype ever reported. In the end, we evaluate the timing performance of the LTE soft base station and a packet loss ratio of less than 0.003 is obtained.

摘要：In order to improve the pollution control effect of nitrogen phosphorus and heavy metals in stormwater runoff by using the constructed wetlands factors such as medium plants pretreatments *** may influence the removal efficiency are discussed based on the current studies. The pollution control effect can be enhanced by the improvement of the design methods the components and management of constructed *** design methods aimed at controlling the stormwater runoff should be based on the hydrological data accumulated for *** development of novel medium and the selection of plants i.e. flood-tolerant and economical should be considered in advance. The management of constructed wetlands should be enhanced and the database of the stormwater in wetlands should be *** discussion above should be effective in improving the pollution control effect in stormwater runoff by applying constructed wetlands.

摘要：A reconfigurable dual-band LNA is presented. The LNA employs switching capacitors and circuit in to realize the dual-band operation. These methodologies are used to design and implement a reconfigurable LNA for IMT-A and UWB application. The LNA is implemented using TSMC-0.13 μm CMOS technology. Measured performance shows an input matching of better than -13.5 dB, a voltage gain of 18-22.8 dB, with an NF of 4.3-4.7 dB in the band of 3.4-3.6 GHz, and an input matching of better than -9.7 dB, a voltage gain of 14.7-22.4 dB, and with an NF of 3.7-4.9 dB in the band of 4.2-4.8 GHz. According to the measure results, the proposed LNA achieves dual-band operation, and it proves the feasibility of the proposed topology.