摘要：针对传统宽带数字波束形成器精度低、主瓣误差大及自导系统中DSP算力紧张的问题,研究一种基于FPGA的鱼雷自导波束形成实现方法。首先介绍最小差异恒定主瓣波束形成算法,通过将优化变量与求解变量相联系,解决了传统算法中波束响应依赖期望主瓣响应的问题,实现由确定到自适应的转化。然后设计基于FPGA的数字波束形成系统结构,完成滤波器模块的建模、综合和实现。最后完成基于FPGA的波束形成实验。通过实验证明,FPGA处理结果与Matlab仿真数据结果误差在10-1量级,信号还原率较高。为波束形成在FPGA硬件设计中的正确性和可靠性提供依据。

摘要：Prosthesis implantation and fat transplantation are common breast *** general,prosthesis implantation alone does not achieve a realistic enough appearance,and fat transplantation alone is difficult to achieve in the correct *** date,no reports have focused on methods of combining fat with implanted prostheses for breast *** a newly designed bionic ink(i.e.,polyether F127 diacrylate(F127DA)&poly(ethylene glycol)diacrylate(PEGDA))and projection-based three-dimensional bioprinting(PBP),we report the development of a new method for printing porous *** was used to improve the printing precision of the prosthesis by increasing the gel point of F127DA and reducing the impact of external *** compression modulus of the printed prosthesis was very close to that of prostheses currently used in clinical practice and to that of natural ***,stromal vascular fraction gel(SVF-gel),a human fat extract,was injected into the pores of the synthesized prostheses to prepare a prosthesis mixed with adipose *** were implanted subcutaneously in nude mice to observe their biological *** 14 and 28 days of observation,the prosthesis showed good biocompatibility,and adipose tissues grew well in and around the *** result shows that a porous prosthesis containing pre-placed adipose tissues is a promising breast reconstruction material.

摘要：路感模拟是线控转向系统开发的关键技术之一,为了提高路感模拟的质量,基于传统转向系统转向阻力矩的产生原理和动力学模型计算方法,设计了线控转向系统的路感力矩;为了降低不确定性系统参数和传感器噪声引起的路感电机扭矩脉动,设计了基于自抗干扰算法的路感电机矢量控制策略,并使用粒子群算法对自抗干扰算法中的控制参数进行优化;基于转向盘中间位置操纵稳定性试验和转向轻便性试验,对路感模拟效果进行了验证。结果表明,基于粒子群优化的自抗干扰路感模拟控制算法具有较强的适应性,能有效实现对路感的精确模拟,并可有效减轻驾驶员负担,相关研究可为线控转向系统的设计提供参考。

摘要：原密封加速度过载开关在进行3500g冲击响应谱失效,本文通过设计计算分析三种失效问题的主要原因,对封加速度过载开关接触系统优化设计和锁紧机构进行优化设计。通过ANSYS仿真实验分析和试验验证结果表明:优化设计后的产品,在3500g冲击响应谱下未出现“锁定机构解锁,导致产品回到初始状态”及“定位杆断裂”失效现象,解决了原产品在3500g冲击响应下失效的技术瓶颈问题。本文为后续密封加速度过载开关类产品的结构设计提供一些可借鉴的经验。

摘要：地下水污染相比于地表水与大气污染,具有隐蔽性、滞后性和不可逆性等特点,污染物进入地下水后,随着水流不断扩散,难以及时找到污染源头并进行有效控制。对于地下水中的污染进行溯源,是进行土壤地下水污染修复的前提条件。同时,水污染事件中污染物来源不清也会导致责任归属难判定,从而引起案件纠纷等系列问题。首先对常见的地下水污染物的种类和来源进行了归纳,之后对目前地下水污染溯源技术和主要研究方向进行了综述,最后结合溯源方法的实践应用提出该方向应用的重难点。

摘要：Electrochemical CO_(2) reduction reaction (CO_(2) RR) offers a practical solution to current global greenhouse effect by converting excessive CO_(2) into value-added chemicals or fuels. Noble metal-based nanomaterials have been considered as efficient catalysts for the CO_(2) RR owing to their high catalytic activity, long-term stability and superior selectivity to targeted products. On the other hand, they are usually loaded on different support materials in order to minimize their usage and maximize the utilization because of high price and limited reserve. The strong metal-support interaction (MSI) between the metal and substrate plays an important role in affecting the CO_(2) RR performance. In this review, we mainly focus on different types of support materials (e.g., oxides, carbons, ligands, alloys and metal carbides) interacting with noble metal as electrocatalysts for CO_(2) RR. Moreover, the positive effects about MSI for boosting the CO_(2) RR performance via regulating the adsorption strength, electronic structure, coordination environment and binding energy are presented. Lastly, emerging challenges and future opportunities on noble metal electrocatalysts with strong MSI are discussed.

摘要：电影虚拟摄制凭借所见即所得的优势已在全球电影工业体系中得到广泛应用,但其后期前置的特点,导致前期高质量资产制作成本投入高,资产有效利用率较低,现场即时调整专业性要求高。人工智能生成内容(AIGC)技术以其高效生成和即时响应的能力可以有效弥补虚拟摄制的上述应用短板。本文通过AIGC技术在概念设计、场景生成、角色创建、动画生成、现场交互调整等各阶段的具体应用,探索人工智能(AI)如何在电影虚拟摄制各环节发挥效能,分析总结AI技术的优势、劣势及其与电影虚拟摄制的适配性,形成一套电影虚拟摄制的智能制作流程和实践方案。

摘要：为了确定高寿命陶瓷刀具材料最优的刀具材料性能配置以获得高寿命陶瓷刀具材料,提出基于刀具寿命的陶瓷刀具材料性能配置方法.通过陶瓷刀具车削超高强度钢300M实验,研究了刀具寿命与刀具材料性能的关系.将刀具寿命分解为硬度、强度、断裂韧性和弹性模量四个指标,综合使用层次分析(AHP)法和指标重要性(CRITIC)对以上指标进行综合评价,获得了最优的刀具性能配置.结果表明:高刀具寿命陶瓷刀具材料最佳性能配置,即硬度、断裂韧性、抗弯强度和弹性模量的权重分别为0.42,0.39,0.05和0.14.这为获得高刀具寿命陶瓷刀具提供了设计目标和方向.

摘要：为提高半导体制冷果蔬配送箱的工作性能,提高半导体制冷片热端散热效率,降低散热系统能耗与质量,搭建水冷半导体果蔬配送制冷箱试验平台,针对水泵流量、散热风机风速、水箱容量对半导体制冷性能的影响进行试验研究。结果表明,导体制冷果蔬配送箱最佳水冷散热参数为:水泵流量为13 cm^3/s,散热风机风速4 m/s,水箱200 m L;在该参数条件下,箱内空气温度从25℃降到7℃仅需580 s,半导体制冷片能耗25 165.20 J,制冷系统总能耗为28 408.10 J,制冷效率26.004%,保证了较快的制冷速度和较小的水箱体积,并减少降温能耗。研究结果为便携式果蔬配送系统的设计和优化提供理论依据。

摘要：余热锅炉汽水平衡控制对实现燃气-蒸汽联合循环机组(combined cycle gas-steam turbine,CCGT)节能减排和经济运行具有重要意义。CCGT频繁变负荷给余热锅炉汽水平衡带来了大幅度扰动,现有控制策略没有考虑系统运行的经济性。因此,提出了一种基于非支配排序遗传算法Ⅱ(non-dominated sorting genetic algorithm Ⅱ,NSGAⅡ)的多目标优化模型预测控制器设计方法。在余热锅炉三冲量液位控制系统的基础上,该方法将系统运行的能耗和效率加入目标函数,结合NSGAⅡ动态求解设备的变负荷控制量。利用国内某CCGT的实际运行数据进行实验,实验结果表明,所提方法在满足稳态跟踪控制的基础上,具有更低的运行成本。