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1.
目的 针对“新国潮”这一新兴的设计现象进行受众关注度研究,旨在剖析“新国潮”设计风格,发现影响“新国潮”受众关注度的设计要素,并展开实验分析,为设计领域的实证研究提供方法层面上的启示,为“新国潮”风格的推广提供设计策略。方法 在从字体、符号和色彩三方面解构“新国潮”设计要素的基础上,通过因素分析方法确定实验数据的信度、效度,运用眼动实验系统和方差分析法从无意注意和有意注意两个阶段实证研究“新国潮”设计要素对受众关注度的影响,并对原因展开分析。结果 在无意注意阶段,书法体、有色彩渐变、高纯度色彩、非象征符号能够获得较高关注度;在有意注意阶段,受众对宋体、有色彩渐变、高纯度色彩、象征符号的关注度更高。结论 研究在提高受众对“新国潮”画面的关注度、发现关注度影响机理和构建设计要素有效表达方面具有重要意义。 相似文献
2.
短波发射机功率稳定一直是通信领域致力改善的重点问题,短波发射机功率不稳定会直接影响无线电通信质量,造成通信失真、表达不清晰等问题。针对上述问题,基于软件校准设计短波发射机功率控制系统。该系统借鉴MVC设计模式搭建系统数据库层、业务逻辑层、控制层以及界面显示层基础框架;将功率计与短波发射机相连,实时采集工作状态下的短波发射机功率数据,通过信号处理器实施处理后并存储,借鉴传输元件,将数据发送到控制器,通过控制器校准短波发射机功率与预期之间的偏差,以偏差量为输入,利用改进PID运算得出控制量,生成控制命令,通过输入输出信号接口板输出命令,控制驱动装置调节短波发射机运行参数,实现功率控制。结果表明:与 控制系统、自动调谐系统应用相比较,在所设计系统应用控制下,100s内短波发射机的功率变化曲线与预期曲线之间的拟合优度指数更大,更接近1,优于对比系统,说明相比于对比系统。本系统控制表现更好,更能维持短波发射机功率稳定,达到了研究目标。 相似文献
3.
The slight-alkalization of generator internal cooling water (GICW) is widely used to inhibit the corrosion of hollow copper conductor and thereby ensure the safe operation of the generator. CO2 inleakage is increasingly identified as a potential security risk for GICW system. In this paper, the influence of CO2 inleakage on the slight-alkalization of GICW was theoretically discussed. Based on the equilibriums of the CO2-NaOH-H2O system, CO2 inleakage saturation was derived to quantify the amount of the dissolved CO2 in GICW. This parameter can be directly calculated with the measured conductivity and the [Na+] of GICW. The influence of CO2 inleakage on the slight-alkalization conditioning of GICW and the measurement of its water quality parameters were then analyzed. The more severe the inleakage, the narrower the water quality operation ranges of GICW, resulting in the more difficult the slight-alkalization conditioning of GICW. The temperature calibrations of the conductivity and the pH value of GICW show non-linear correlations with the amount of CO2 inleakage and the NaOH dosage. This study provides insights into the influence of CO2 inleakage on the slight-alkalization of GICW, which can serve as the theoretical basis for the actual slight-alkalization when CO2 inleakage occurs. 相似文献
4.
《Contact lens & anterior eye》2022,45(5):101497
PurposeThe assessment of symptoms of dry eye disease using a questionnaire is an effective and simple method of quantifying symptoms. The aim of this study was to translate the SPEED questionnaire and adapt it for the Italian language and verify the main psychometric performance of the translated version, including repeatability and agreement.MethodsThe SPEED questionnaire was translated into Italian following a standard methodology. The resulting questionnaire was administered to 206 adult participants in order to perform a validation analysis. A subgroup of 82 participants was retested after one week to give a repeatability and agreement assessment.ResultsInternal consistency showed an alpha of 0.852 (95% CI 0.818–0.881) and no unnecessary items. The factor analysis showed a saturation for three main factors related to (i) Dryness and Soreness, (ii) Fatigue, and (iii) Burning. Repeatability was high, with a CCC of 0.896 (95% CI 0.844–0.931). Agreement analysis showed no significant bias between sessions and an interval of agreement of 5 points for SPEED score.ConclusionThe translation and adaptation of the SPEED questionnaire for the Italian language have demonstrated good psychometric properties for the translated questionnaire, confirming and expanding the original psychometric characteristics. Consequently, the SPEED questionnaire could be used to measure the presence of symptoms of dry eye quantitatively. 相似文献
5.
Catherine O'Leary Yvonne de Kluizenaar Piet Jacobs Wouter Borsboom Ian Hall Benjamin Jones 《Indoor air》2019,29(3):423-438
There is growing awareness that indoor exposure to particulate matter with diameter ≤ 2.5 μm (PM2.5) is associated with an increased risk of adverse health effects. Cooking is a key indoor source of PM2.5 and an activity conducted daily in most homes. Population scale models can predict occupant exposures to PM2.5, but these predictions are sensitive to the emission rates used. Reported emission rates are highly variable and are typically for the cooking of single ingredients and not full meals. Accordingly, there is a need to assess PM2.5 emissions from the cooking of complete meals. Mean PM2.5 emission rates and source strengths were measured for four complete meals. Temporal PM2.5 concentrations and particle size distributions were recorded using an optical particle counter (OPC), and gravimetric sampling was used to determine calibration factors. Mean emission rates and source strengths varied between 0.54—3.7 mg/min and 15—68 mg, respectively, with 95% confidence. Using a cooker hood (apparent capture efficiency > 90%) and frying in non‐stick pans were found to significantly reduce emissions. OPC calibration factors varied between 1.5 and 5.0 showing that a single value cannot be used for all meals and that gravimetric sampling is necessary when measuring PM2.5 concentrations in kitchens. 相似文献
6.
为了解决长行程定子不连续永磁直线同步电机存在的因无法全程安装位置传感器和不同动子和定子之间的电磁参数不固定所造成的控制性能下降的难题,提出一种在每一段定子内先进行参数标定,再进行速度控制的控制系统设计。首先,在动子进入过程中,对电机进行电磁参数标定,根据标定参数对控制器参数进行调整,以达到更好的控制效果。然后,使用无位置传感器控制系统使动子快速达到设定速度值并稳定运行。实验结果表明:动子进入过程参数标定精度分别为0.002Wb和0.000 4H;无位置传感器控制中位置估计精度为0.63mm,速度收敛时间为0.45s,稳态误差为0.02m/s。基本满足永磁直线同步电机用于长行程运输的控制快速性、稳定性等要求。 相似文献
7.
《Mechatronics》2021
Producing a stable and agile bionic eye for visual image acquisition in robotics is a challenging task. In this paper, we design a bionic eye with mirror-symmetric distribution and cross-connection of flexible ropes. This mechanism is based on oculomotor law and the physiological structure of the extraocular muscles (EOMs). Specifically, the basic structural parameters are determined by Listing’s law, and the unique connection of the flexible ropes can realize the functions of the recti and oblique muscles. Furthermore, to mimic the trochlea structure, a pulley mechanism is constructed to permit the free movement of the flexible ropes. Through simulation and physical experiments, it is demonstrated that the bionic eye mechanism can move with agility under the structural parameters. The experimental results indicate that the proposed bionic eye mechanism has a superior motion accuracy of 2.798 mm, which is 6.7% of the maximum motion distance, and the repeatable accuracy of the mechanism can up to 0.210 mm. 相似文献
8.
虚拟手技术是虚拟现实技术中的一种交互方式,是指通过手势识别技术将人的真实手映射到虚拟环境中并与虚拟物体进行交互操作的人机交互方式。主要应用于虚拟训练、虚拟手术和虚拟装配等领域。对虚拟手交互的约束类对象进行了研究,提出了基于运动学的约束类物体操作方法,解决了阀门类有约束物体交互中虚拟手姿态不真实、操作不可控的问题。设计实验验证了基于运动学的方法能以符合实际操作的效果完成虚拟现实系统中的操作任务,可以应用到虚拟训练、虚拟装配等仿真平台。 相似文献
9.
A new strategy for the selective coating of tin sulfide (SnS) on the surface of moth‐eye patterned (MEP) conducting polymer film is studied by considering the optical properties of the antireflective moth‐eye pattern and flexibility of polymer films. The semiconductor SnS is selectively coated on the surface of MEP microdomes of poly(3,4‐ethylenedioxythiophene) poly(styrene‐sulfonate) (PEDOT:PSS) film. The SnS coated MEP film is obtained by using pore selectively SnS thin layer functionalized polystyrene honeycomb‐patterned porous (HCP) film as a template. Aqueous PEDOT:PSS solution is poured on the SnS functionalized HCP films and detached for the fabrication of SnS coated MEP films. The films show a satisfactory photo‐responsive property under solar stimulated light illumination due to the antireflective MEP structure of PEDOT film and homogenous SnS coating on the surface of the conducting polymer. 相似文献
10.
为了快速准确地输出各种工作姿势风险评估结果,提出采用Kinect v2与卷积神经网络识别人体各关节角度,并输出标准姿势风险的评估得分。首先使用亚像素角点提取的棋盘标定算法标定Kinect两个摄像头,其次使用改进后的双边滤波对深度图像去噪,使用卷积神经网络识别人体关节二维位置,结合深度信息获取实际三维坐标并计算人体关节角度,最后输出姿势风险评估得分。通过两种实验分别验证了提出的Kinect角度识别与姿势评估的准确性,表明该方法关节角度识别与姿势风险评估的准确率均较高,是一种低成本、高可靠性的姿势评价方法,具有一定的科学意义和工程应用价值。 相似文献