基于模糊PID的温度控制系统

详细介绍了一种基于单片机模糊PID算法的数字温度控制系统,该系统硬件主要由单片机、温度检测、人机接口、加热丝、PWM（脉宽调制）移相触发等构成。通过软件编程实现模糊逻辑控制,模糊PID控制器以温度偏差和偏差变化作为输入,以△KP,△KI,△KD作为输出,整个系统通过自动调整PID的参数KP、KI、KD使PID控制器能够通过改变输出的PWM脉冲来控制执行机构使系统保持预定温度。对温度控制系统进行了多次实验测试,实验结果表明此温控系统在较大的温度范围内具有响应快、精确度高的特点。     

图像分割中的交叉熵和模糊散度算法

本文将交叉熵和模糊散度应用于图像分割中,提出了中最优灰度值选取算法,其一是基于均匀分布假设的最小交叉熵算法,其二是利用后难概率的最大类间交叉熵算法,其三是类间最大模糊散度的改进算法,其四是最小模糊散度算法,针对图像阈什化分割的要求,在后两种算法中构造一种新的模糊录改度函数,本文采用均匀测试和开头测试比较各算法的性能,利用多种类型测试 是到的分割结果,显示了所筛算法的有效性和通用性。     

Identification of inpainted images and natural images for digital forensics

Image forensics is a form of image analysis for finding out the condition of an image in the complete absence of any digital watermark or signature.It can be used to authenticate digital images and identify their sources.While the technology of exemplar-based inpainting provides an approach to remove objects from an image and play visual tricks.In this paper,as a first attempt,a method based on zero-connectivity feature and fuzzy membership is proposed to discriminate natural images from inpainted images.Firstly,zero-connectivity labeling is applied on block pairs to yield matching degree feature of all blocks in the region of suspicious,then the fuzzy memberships are computed and the tampered regions are identified by a cut set.Experimental results demonstrate the effectiveness of our method in detecting inpainted images.     

PCB工业“绿色生产”的好形式——建立电子电路“工业园区”的启示

文章概述了在“绿色生产”的挑战下,最佳方案是采用“工业园区”和“技术革命”的道路。从“节能减排”和“制造过程”等角度看,喷墨打印技术／印制电子技术是最有前途的。     

模糊支撑半径变量贝叶斯网络多态系统故障概率分析

针对现有隶属函数描述系统及部件故障状态的不足,构建了一种含模糊支撑半径变量的隶属函数来描述部件故障状态,提出了一种基于模糊支撑半径变量的贝叶斯网络多态系统故障概率计算方法。在隶属函数的构造中,用变量代替精确值描述隶属函数模糊支撑半径,建立了含模糊支撑半径变量的隶属函数;并将其引入贝叶斯网络,利用桶消元法对多态系统叶节点故障概率进行分析,得到叶节点故障概率变化曲线。将所提出的方法与文献中基于模糊支撑半径为定值的隶属函数贝叶斯网络方法相比较,验证了方法的有效性。最后,将该方法应用到数控机床主轴系统故障分析实例中,对叶节点故障概率进行计算。结果表明,该方法能够有效解决多态系统故障状态隶属函数选择中的主观性问题。     

基于SERVQUAL模型的水上娱乐设施设计研究

目的 由于水上娱乐设施具有普适性,而各景区气候、地形、水系和发展重点不同,本文以木兰天池水上娱乐设施为例,旨在为其提出设计优化策略并对其进行设计研究。方法 首先,提取自然环境要素因子和娱乐设施要素因子,得出综合要素因子分类,即人员服务、设施服务、设施安全;其次,以SERVQUAL模型的五个维度为基准,构建出服务评价量表并采用选项隶属度计算进行筛选,得出最终服务评价量表;随后运用调查问卷、信度效度分析、因子分析;最后,计算出各指标感知与期望的差值。结果 舒适度、分流分区、环境安全、材料材质安全、结构安全、维护维修是木兰天池景区水上娱乐设施的主要设计要素,以此进行木兰天池景区水上娱乐设施设计研究。结论 此方法为设计景区同类水上娱乐设施提供了理论依据。     

用模糊神经网络模型评估电能质量

为了综合量化评估各种电能质量,实现按质论价、优质优价的购电原则,建立公平的电力市场,提出了结合人工神经网络和模糊识别理论,构造出模糊神经识别网络;根据电能质量评估的实质,构建了电能质量综合评估的模糊神经网络模型。研究表明,模型提高了识别系统的柔性处理能力,具有很强的自组织、自学习和自适应能力,可以使输出结果唯一、客观;模型不仅可确定电能质量的等级,还能评估某一等级的电能质量,从而识别同一等级电能质量的差异,分类能力和排序能力较强;模型引入隶属度概念,使评估结果更加具体。实例计算结果表明,模糊神经网络模型用于电能质量综合评估,其评估结果更为客观、合理。     

National Museum of Qatar

National Museum of Qatar – Super‐complex steel structures, envelope and 3D BIM. Doha, the capital of Qatar, is developing fast towards a global hub for finance, culture and tourism. The new flagship, the National Museum of Qatar (NMoQ), is currently being completed based on a design by Atelier Jean Nouvel, Paris. The iconic three‐dimensional geometry and the size of the project were extremely challenging for both the design and the works on site.     

Factors affecting conception rates following artificial insemination or embryo transfer in lactating Holstein cows

The objective of this study was to evaluate the factors that may affect conception rates (CR) following artificial insemination (AI) or embryo transfer (ET) in lactating Holstein cows. Estrous cycling cows producing 33.1 ± 7.2 kg of milk/d received PGF_2α injections and were assigned randomly to 1 of 2 groups (AI or ET). Cows detected in estrus (n = 387) between 48 and 96 h after the PGF_2α injection received AI (n = 227) 12 h after detection of estrus or ET (n = 160) 6 to 8 d later (1 fresh embryo, grade 1 or 2, produced from nonlactating cows). Pregnancy was diagnosed at 28 and 42 d after estrus, and embryonic loss occurred when a cow was pregnant on d 28 but not pregnant on d 42. Ovulation, conception, and embryonic loss were analyzed by a logistic model to evaluate the effects of covariates [days in milk (DIM), milk yield, body temperature (BT) at d 7 and 14 post-AI, and serum concentration of progesterone (P4) at d 7 and 14 post-AI] on the probability of success. The first analysis included all cows that were detected in estrus. The CR of AI and ET were different on d 28 (AI, 32.6% vs. ET, 49.4%) and 42 (AI, 29.1% vs. ET, 38.8%) and were negatively influenced by high BT (d 7) and DIM. The second analysis included only cows with a corpus luteum on d 7. Ovulation rate was 84.8% and was only negatively affected by DIM. Conception rates of AI and ET were different on d 28 (AI, 37.9% vs. ET, 59.4%) and 42 (AI, 33.8% vs. ET, 46.6%) and were negatively influenced by high BT (d 7). The third analysis included only ovulating cows that were 7 d postestrus. Conception rates of AI and ET were different on d 28 (AI, 37.5% vs. ET, 63.2%) and 42 (AI, 31.7% vs. ET, 51.7%) and were negatively influenced by high BT (d 7). There was a positive effect of serum concentration of P4 and a negative effect of milk production on the probability of conception for the AI group but not for the ET group. The fourth analysis was embryonic loss (AI, 10.8% vs. ET, 21.5%). The transfer of fresh embryos is an important tool to increase the probability of conception of lactating Holstein cows because it can bypass the negative effects of milk production and low P4 on the early embryo. The superiority of ET vs. AI is more evident in high-producing cows. High BT measured on d 7 had a negative effect on CR and embryonic retention.     

对“电机及拖动基础“课程教学方法的探讨

针对"电机及拖动基础"课程在教学过程中出现的一些问题,分析了问题出现的原因,并结合多年的教学实践经验,从4个方面提出了解决问题的方法.