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101.
施荣晓 《自动化技术与应用》2022,41(1):167-170,181
为了在竞争日益激烈的市场中提高竞争力,达到个性化销售目的,创造更大品牌价值,提出一种基于农产品品牌社会责任的消费者智能消费推荐研究。实验利用离散函数及品牌认可度描述推荐结果,分析推荐结果指数,证明基于社会责任的智能推荐研究令消费者认可度更高,与文献方法比较推荐结果有更高的精确度,设计的推荐模型可实现农产品个性销售目的,令农产品有更大的发展空间。 相似文献
102.
《中国有色金属学会会刊》2022,32(10):3404-3419
Mixed bacteria were enriched from heavy metals mine soil for cadmium (Cd(II))-containing wastewater treatment. Batch adsorption experiment results showed that the optimal pH, temperature, initial Cd(II) concentration, and biomass dosage were 6.0, 30 °C, 20 mg/L, and 1 g/L, respectively. Living biomass exhibited better Cd(II) removal efficiency (91.97%) than autoclaved biomass (79.54%) under optimal conditions. The isotherms and kinetics of living biomass conformed to the Langmuir isotherm model and pseudo-first-order kinetic model, respectively. FTIR results implied that amine groups, hydroxyl groups and phosphoric acid play an important role in the Cd(II) adsorption process, while XRD results showed that crystalline Cd(OH)2 and CdO were obtained. After Cd(II)-containing wastewater treatment exposure, the dominant bacteria genera included Comamonas (39.94%), unclassified_f__Enterobacteriaceae (34.96%), Ochrobactrum (14.07%), Alcaligenes (4.84%), Bordetella (2.07%), Serratia (1.04%), and Bacillus (1.01%). Function prediction showed that the abundance of metabolic genes changed significantly. This study proposes the potential application of mixed bacteria for Cd(II)-containing wastewater treatment. 相似文献
103.
104.
Meaning making by leadership in a crisis is required to reduce uncertainty. We used analytic criteria for meaning making suggested by crisis management literature to investigate public leaders’ quotations in news coverage of a health crisis. The quotations were examined in terms of the five frame functions, which include offering a credible explanation of what happened, offering guidance, instilling hope, showing empathy, and suggesting that leaders are in control. The Middle East respiratory syndrome outbreak in South Korea was examined. As a result, the most salient frame function identified was displaying they are in control of the emergency, followed by offering guidance and explaining what happened. The salience of leaders’ meaning making disappeared in coverage by a liberal newspaper. 相似文献
105.
经验模态分解(EMD)方法是一个以信号内在物理频率成分为对象的自适应时频分析方法,而常见的非平稳信号分析方法,比如小波分析,它需要选择小波基,不同小波基的分析结果不同;拉曼光谱信号是典型的非线性和非平稳信号,EMD方法充分地保留了信号本身的非线性和非平稳的特征,适应于拉曼光谱信号的分析。实验在自行研制的拉曼光谱测试平台上获得了原始的拉曼光谱信号,并通过经验模态分解将信号分解成不同频率的10个本征模式分量,信号能量集中在750cm-1和1500cm-1左右,最后进行了频率成分分析和去噪处理,并和小波分析方法进行了对比,验证了EMD方法的有效性和实用性,该方法在拉曼光谱信号分析中有较好的应用前景。 相似文献
106.
在信息分组以连续时间规律到达系统的基础上,对于轮询系统中不同优先级的业务问题,提出区分优先级的两级轮询服务模型。首先,在该模型中,低优先级站点采用门限服务,高优先级站点采用完全服务;然后,在高优先级转低优先级时,将传输服务与转移查询并行处理来降低服务器在查询转换期间所耗费的时间,提高轮询系统的效率;最后,运用马尔可夫链和概率母函数的方法建立了系统的数学模型,通过对数学模型精确解析,得到了连续时间两级服务系统每个站点的平均排队队长和平均等待时间的表达式,精确解析出平均排队队长和平均等待时间的值。仿真实验结果表明:理论计算值与实验仿真值近似相等,说明理论分析正确合理。该模型既能保障低优先级站点服务质量,又能为高优先级站点提供优质服务。 相似文献
107.
This study presents a system identification method based on polynomial modulating function for fractional-order systems with a known time-delay involving input and output noises in the time domain. Based on the polynomial modulating function and fractional-order integration by parts, the identified fractional-order differential equation is transformed into an algebraic equation. By using the numerical integral formula, the least squares form for the system identification is obtained. In order to reduce the effect of noises existing in the input and output measurements, the compensation method for the input and output noises is also studied by introducing an auxiliary high-order fractional-order system in the revised identification algorithm. Finally, the effectiveness of the proposed algorithm is verified by the simulation result of an illustrative example and the experimental result of temperature identification for a thermal system. 相似文献
108.
In this paper, a robust controller for a Six Degrees of Freedom (6 DOF) coaxial octorotor helicopter control is proposed in presence of actuator faults. Radial Base Function Neural Network (RBFNN), Fuzzy Logic Control approach (FLC) and Sliding Mode Control (SMC) technique are used to design a controller, named Fault Tolerant Control (FTC), for each subsystem of the octorotor helicopter. The proposed FTC scheme allows avoiding difficult modeling, attenuating the chattering effect of the SMC, reducing the rules number of the fuzzy controller, and guaranteeing the stability and the robustness of the system. The simulation results show that the proposed FTC can greatly alleviate the chattering effect, good tracking in presence of actuator faults. 相似文献
109.
This paper investigates parameter identification of nonlinear Wiener-Hammerstein systems by using filter gain and novel cost function. Taking into account the system information is corrupted by noise, the filter gain is exploited to extract the system data. By using several auxiliary filtered variables, an extended estimation error vector is developed. Then, based on the discount term of the extended estimation error and the penalty term on the initial estimate, a novel cost function is developed to obtain the optimal parameter adaptive law. Compared with the conventional cost function which is composed of the square sum of output error, the proposed algorithm based on the cost function of this paper can provide faster convergence rate and higher estimation accuracy. Furthermore, the convergence analysis of the proposed scheme indicates that the parameter estimation error can converge to zero. The effectiveness and practicality of the proposed scheme are validated through the simulation example and experiment on the turntable servo system. 相似文献
110.
《Planning》2018,(2)
抗血小板药物在各种动脉血栓性疾病防治中具有重要地位。虽然目前抗血小板药物多采用固定剂量给药,但不同患者对抗血小板治疗的反应性存在明显差异。治疗后的血小板高反应性或低反应性可能与血栓事件或出血事件风险相关。基于血小板功能检测的个体化抗血小板治疗方案可能有助于预防血栓或出血不良事件的发生,但目前仍缺乏上述治疗策略能够最终改善患者预后的确切临床证据。迄今为止,对于接受抗血小板治疗的患者是否应常规进行实验室监测仍存在诸多争议。本文对抗血小板治疗反应多样性的成因及血小板功能检测是否可用于指导个体化抗血小板治疗进行讨论。 相似文献