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1.
OFDM is a high-speed signal transmission technology in wireless environment. In wireless channels, the frequency response curve is generally non-flat. MIMO technology can effectively increase system capacity, improve system performance, and improve network coverage and transmission reliability. OFDM technology can effectively resist intersymbol crosstalk caused by multipath propagation by adding a certain length of redundant guard interval in front of transmission symbols. According to the channel estimation and signal detection algorithms in MIMOOFDM systems, this paper will choose a better algorithm to implement MIMOOFDM systems and channel estimation and signal detection algorithms. Theoretical analysis and simulation results show that the optimal detection algorithm has the best performance, but its complexity is exponentially related to the number of antennas and modulation order. The architecture for dense texture analysis is developed based on Field Programmable Gate Array FPGA device which is a general engine for high-speed image processing. In order to maximize the performance, our architecture is designed for minimizing consumed resources. As explained in subsection our architecture is composed of two main operations, namely the AH based sum and difference of images and the calculus of texture features  相似文献   
2.
季丽英 《广州化工》2011,39(10):14-15,22
目前我国正大力发展轨道交通,主要是地铁和轻轨,同时产生了一系列的环境问题。针对人群密集的地铁微环境空气质量和轻轨的噪声问题,讨论了我国轨道交通环境问题的主要表现及研究现状,并提出了建议。  相似文献   
3.
高鑫  张亮  李博 《中国酿造》2015,34(12):88
该文通过添加不同发酵剂用量制作了3种硬质蒙古干酪,并对硬质蒙古干酪的理化性质、蛋白质和脂肪水解程度、微观结构等进行了研究。结果表明,随着发酵剂用量增多,除D-乳酸含量外,其他理化指标均随发酵剂用量的增大而减小;粗蛋白质和粗脂肪的含量减少;pH 4.6-可溶性氮(SN)含量和12%三氯乙酸(TCA)-SN含量均增加,表明干酪中蛋白质和脂肪的水解程度增大;游离氨基酸和游离脂肪酸的含量增加,表明干酪的风味物质增多。随着发酵剂用量的增多,干酪酸化速度加快,质地相对松散。最终确定发酵剂使用量为1.0 g/L,在此条件下,脂肪和蛋白质的水解程度适中,游离氨基酸种类丰富,能够满足干酪风味化合物生成的需求。  相似文献   
4.
新冠肺炎疫情发生以来,全国上下众志成城,大家都在为防控疫情作出自己的贡献。为提升大学生在疫情防控期间及返校后的战"疫"能力,从新冠肺炎流行病学、临床医学、社会治理等角度出发,指导高校大学生科学理性应对新冠肺炎,保证自身身心健康,传递"治未病、重预防"的健康理念,提高基本卫生常识和科学防护能力,齐心协力打赢这场抗"疫"攻坚战。  相似文献   
5.
不少图形应用场合中,需要事先对倾斜的图形进行矫正,本文以Java语言结合Opencv库,对倾斜字符图片进行增强图形特征预处理、边缘检测、寻找图形最大边缘轮廓、旋转矫正图形等一系列处理,达到矫正字符图形的效果。  相似文献   
6.
绿豆糕是流行于全国各地的传统甜品,试验改进传统绿豆糕的制作工艺,以菊粉部分替代绿豆糕中蔗糖和黄油,筛选出低糖营养和风味俱佳的绿豆糕配方。与传统绿豆糕相比,该产品强化菊粉,具有低糖低能量的特点,迎合消费者对天然健康的追求,同时拓展菊粉在食品工业中的应用领域。  相似文献   
7.
目的:探究原花青素B2对高脂膳食小鼠钙代谢异常与股骨基因表达的影响。方法:将27 只C57BL/6雄性小鼠随机分为3 组:对照组、高脂膳食组和原花青素B2组,原花青素B2添加量为0.2%(以饲料质量计);持续饲喂8 周后分析小鼠体质量、血浆脂质水平、钙内稳态、钙吸收能力和骨矿物含量的变化,并运用真核有参转录组技术分析小鼠股骨基因表达变化情况。结果:原花青素B2能够显著提高小鼠钙净吸收和贮留能力(P<0.05),并显著降低血脂水平和甲状旁腺素质量浓度,改善高脂膳食导致的小鼠骨矿物、股骨钙含量和最大荷载量的降低。高通量测序发现49 个差异共表达基因,原花青素B2可干预其中48 个基因的表达,基因本体论富集分析发现其归属于生物进程和细胞组分两个分支,京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)富集分析发现共有13 条通路具有显著性富集意义(P<0.05),其中涉及钙代谢相关信号转导和代谢通路5 个基因(Cdkn2a、Adrb1、Fcgr4、Aldh1a3和Calml3)的表达量发生显著改变(P<0.05)。与高脂膳食组相比,原花青素B2下调Cdkn2a、Adrb1、Fcgr4基因表达量分别为9.19、3.68 倍和3.61 倍,上调Aldh1a3和Calml3基因的表达量分别为2.06 倍和3.29 倍。结论:原花青素B2具有干预高脂膳食导致的小鼠钙代谢异常的作用,其可能与下调破骨细胞活性与上调成骨细胞活性相关基因的表达有关。  相似文献   
8.
唐文潇  肖瀛  蒋天宁  姜峰  朱婧  周一鸣 《食品科学》2022,43(24):239-248
以亚洲咖啡豆为研究对象,分别选取浅、中、深3 种烘焙度的中国云南和印度尼西亚苏门答腊产的卡蒂姆种咖啡豆,比较分析冷萃与热萃方式对萃取浓度、萃取率、可滴定酸、总酚、总糖、咖啡因、葫芦巴碱、绿原酸、抗氧化活性与挥发性成分的差异,并进行主成分分析,从而探究烘焙度对冷萃咖啡理化指标与风味成分的影响规律。结果表明,随着烘焙度增加,冷萃咖啡的萃取浓度、萃取率均显著上升,可滴定酸、总酚、葫芦巴碱、绿原酸、抗氧化活性均显著下降(P<0.05)。冷萃咖啡较热萃咖啡拥有更高的萃取浓度、萃取率与总糖含量(P<0.05),而可滴定酸、总酚含量、抗氧化活性较热萃显著偏低(P<0.05)。经顶空固相微萃取-气相色谱-质谱检测分析发现,浅烘咖啡豆萃取液中的挥发性成分含量显著低于烘焙度高的咖啡萃取液,深烘咖啡豆萃取液中挥发性成分种类与总含量最多。进一步通过主成分分析能较好区分冷萃和热萃咖啡,两者挥发性成分贡献率具有较大差异。2-丁酮、2-丁烯醛等花香类物质对浅烘冷萃咖啡贡献率更高,而2-甲基吡嗪、糠醇等呈现烘焙坚果类香气物质对浅烘热萃咖啡贡献率更高;2,6-二乙基吡嗪、川芎嗪等烘焙坚果类香气物质对中烘冷萃和热萃咖啡具有较高的贡献率;2-乙烯基呋喃、甲基糠硫醇、2,5-二乙基吡嗪、糠基甲基硫醚等物质对深烘冷萃咖啡有较高贡献率,二甲基二硫、对甲酚、1-甲基吡咯等物质对深烘热萃咖啡贡献率更高。相对于热萃咖啡,烘焙度对冷萃咖啡抗氧化能力与挥发性成分的影响更大。  相似文献   
9.
The current pattern in the advancement of sensor frameworks looks for approaches to give more precision and goal, while simultaneously diminishing the size and force utilization. The utilization of Field Programmable Gate Arrays (FPGAs) gives explicit reprogrammable equipment innovation that can be appropriately abused to acquire a reconfigurable sensor framework. This variation ability empowers the execution of complex applications utilizing the fractional configurability at a low-power utilization. For profoundly requesting undertakings FPGAs have been supported because of the high proficiency gave by their design adaptability (parallelism, on-chip memory, and so forth), configurability and amazing execution in the advancement of calculations. FPGAs have improved the presentation of sensor frameworks and have set off an away from in their utilization in new fields of use. Another age of more astute, reconfigurable and lower power utilization sensors is being created in Spain dependent on FPGAs. These improvements is introduced, portraying also the FPGA innovations utilized by the distinctive exploration gatherings and giving a review of future examination inside this field. It depends on a Field Programmable Gate Array (FPGA) gadget. On account of this the equipment is entirely adaptable and gives the stage one of a kind open doors for exploration of a wide scope of models, applications and sign handling calculations. The stage has been named wearable games equipment's, for–Attached Sensor Platform.  相似文献   
10.
Robust dynamic speed response with less maintenance and efficient operation makes the Brushless Direct Current (BLDC) motors as an oblivious choice for many motoring applications which needs instantaneous speed control while developing high torque. This paper proposes Jaya optimization Algorithm on Xilinx platform for BLDC Motor and Fractional Order Proportional Integral Derivative controller to improve its efficiency through minimizing the ripples present in the Torque of the motor. The control strategy of torque controller works with the combinations of Xilinx and optimization algorithms. In this proposed controller, the strategy of control is achieved after deriving the BLDC motor's dynamic mode there after the electronic interaction with BLDC motor is enrooted with the Math lab/Simulink model while tactically utilizing Xilinx tools for all kind of co-simulation in the same model. Initially the dynamic model of a BLDC motor drive is derived and the control topology is designed with the help of the proposed controller. The controlling mechanism established in this paper is effective and efficient in minimizing the ripples present in the torque of the motor. The proposed controller is utilized for possible low-cost and high-performance industrial applications. The results are obtained and analyzed with existing methodologies and it shows that the proposed technique outperforms the existing models.  相似文献   
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