The principle and fundamental characteristics of brushless three-phase synchronous induction motor with two stators

Brushless three-phase synchronous motor involving a rotating ac exciter on the same shaft as the motor and with the windings linked through a shaft-mounted rectifier is widely used as medium and large capacity machines. However, the motor needs to fit with damping windings for self-starting outside of the field winding in the rotor and needs to equip discharge resistance with complex electronic device to dispose of electromagnetic force induced in the field winding at starting. Therefore, the rotor structure is very complex, and there are disadvantages, especially for the robust and highly reliable motor that is desired. To solve the problem found in traditional motors, the authors proposed a brushless three-phase synchronous induction motor with two stators and one wound rotor. This problem is solved because the proposed motor is of two-stators structure: the rotor winding operates as a secondary winding of induction motor at starting and as the field winding at synchronous operation. The motor can self-start as a wound-rotor induction motor without external secondary resistance. Therefore, discharge resistance is not necessary; the starting equipment is very simple and the rotor structure is robust. It is possible to start with high torque. In this paper, the basic constitution of the proposed motor and the principles of operation are described in detail. The experimental results at starting and pulling into synchronism are shown for confirming the principles of operation and the experimental and numerical results of the starting characteristics. The load ones and the generating ones are shown and then the practical use of the proposed motor is confirmed.     

基坑支护中水土压力合算与分算的综合分析

分析了水土分算和水土合算的计算方法，并给出了在不同情况下水土分算的合理计算公式。提出了当采用不固结不排水强度指标时的土压力计算方法。通过将这些算法与实际工程的比较发现了“广义”水土合算法的不安全性，并找出了几种合理的算法。     

冶金企业供电线路设计探讨

为了满足冶金企业大容量供电的需要,采用相分裂导线方式供电,减少出线回路和出线走廊,经济效益显著。     

典型汽车涂装废水处理工艺

针对汽车涂装废水中含有树脂、表面活性剂、重金属离子、油、颜料等污染物，特别是其中的电泳废水、喷漆废水成份复杂，浓度高，可生化性差的，采用分质处理、混凝沉淀、混凝气浮、砂滤等工艺对涂装废水进行处理，取得了良好效果：CODCr去除率大于80％。实际运用表明，该工艺在技术和经济上均是合理可行的。     

UPS输出端中性线接地问题探讨

从UPS工作原理入手,分析单相UPS和三相UPS“另起的系统”的接地问题,结论：UPS输出端的中性线做重复接地的规定有误。     

3D Semantic Deep Learning Networks for Leukemia Detection

White blood cells (WBCs) are a vital part of the immune system that protect the body from different types of bacteria and viruses. Abnormal cell growth destroys the body’s immune system, and computerized methods play a vital role in detecting abnormalities at the initial stage. In this research, a deep learning technique is proposed for the detection of leukemia. The proposed methodology consists of three phases. Phase I uses an open neural network exchange (ONNX) and YOLOv2 to localize WBCs. The localized images are passed to Phase II, in which 3D-segmentation is performed using deeplabv3 as a base network of the pre-trained Xception model. The segmented images are used in Phase III, in which features are extracted using the darknet-53 model and optimized using Bhattacharyya separately criteria to classify WBCs. The proposed methodology is validated on three publically available benchmark datasets, namely ALL-IDB1, ALL-IDB2, and LISC, in terms of different metrics, such as precision, accuracy, sensitivity, and dice scores. The results of the proposed method are comparable to those of recent existing methodologies, thus proving its effectiveness.     

基于自适应哈夫曼编码的密文可逆信息隐藏算法

随着云存储和隐私保护的发展,密文域可逆信息隐藏作为一种可以在密文中嵌入秘密信息,保证嵌入后的信息可以无错误提取,并能无损恢复原始明文图像的技术,越来越受到人们的关注.本文提出了一种基于自适应哈夫曼编码的密文域可逆信息隐藏算法,对不同的图像采用不同的哈夫曼码字编码腾出空间来嵌入秘密信息.首先利用自然图像相邻像素间的相关性对原始明文图像进行像素值预测,从最高有效位到最低有效位,对原始像素值和预测像素值的相同比特位进行自适应的哈夫曼编码标记.然后,利用流密码对原始明文图像进行加密.最后在腾出的空间,通过位替换来自适应的嵌入秘密信息.由于哈夫曼编码和解码的可逆性,合法接收者可以对原始明文图像和秘密信息实现分离的无损恢复和提取.实验结果表明,与现有的几种方法相比,本文提出的方法具有更好的安全性和更高的嵌入率,在BOSSBase、BOWS-2和UCID三个数据集上的平均嵌入率比MPHC算法分别提高了0.09bpp、0.062 bpp和0.06bpp,在最佳情况下比MPHC算法能分别高出0.958 bpp、0.797 bpp和0.320 bpp,最差情况下的嵌入率比MPHC算法也分别高出了 0.01 bpp、0.039 bpp和0.061 bpp.     

施工方法对整体式闸室墙后土压力的影响分析

为研究施工方法对闸室墙后土压力分布的影响,以江苏某船闸工程为背景,采用非线性有限元方法模拟施工过程,土体采用D-P模型,在闸墙与回填土之间、闸底板与地基土之间设置接触单元,模拟接触面滑移特性,得到了不同施工方法的闸室墙后土压力分布,并与船闸规范推荐的计算方法进行比较。研究成果可供船闸设计施工参考。更多还原     

露天台阶爆破矿岩交界处损失贫化控制系统

露天台阶开采推进至矿岩交界处时,爆破设计造成的损失贫化对矿山的经济效益影响较大。为科学地进行矿岩交界处的爆破设计和损失贫化控制,结合爆破后冲线位置和爆破漏斗原理,提出矿岩交界处损失贫化控制系统,其功能架构主要包括数据输入、参数设置、损失贫化计算、采样数据拟合、损失贫化查询、优化决策和显示输出等。该系统在三维空间中计算损失贫化,使结果更加准确,并引入最小二乘拟合方法表达后冲线位置与损失贫化的关系,为查询和优化决策提供基础。在VS2010环境下研发出该系统,对内蒙古乌努格吐山铜钼矿的矿岩交界处损失贫化控制试验表明,该系统科学有效。     

基坑支护中水土压力合算与分算的计算分析

对支护结构土压力的现状进行讨论和分析，比较分析水土分算和水土合算的计算方法，由工程实例的计算分析，得到考虑渗流水土分算的计算方法与，实际情况符合得较好，是一种具有实际运用价值的方法。