基于重分配小波尺度图的转子系统支座松动故障的研究

介绍了重分配小波尺度图,并通过分析仿真信号将传统小波尺度图与重分配小波尺度图进行比较,结果发现重分配小波尺度图可在一定程度上提高尺度图的聚集性,减少干扰项。通过建立转子松动故障的仿真实验台,把实验采集到的发生松动故障的振动信号,利用重分配小波尺度图和三维谱振图进行分析,结果表明,三维谱振图可以大体上显示频谱信息,重分配小波尺度图可以进一步对松动故障信号进行细化分析,两者结合可以更好地识别转子支座松动故障。

天空实时全偏振成像探测器设计与搭建

生物利用天空偏振光进行导航的方式给科研人员很大的启发,越来越多的学者正在进行这方面的研究。精确的天空偏振场图是进行偏振导航的前提条件,为了获取更加准确的天空偏振场图,许多成像式偏振探测装置被开发出来。本文提出了一种新型的实时全偏振一体式成像探测传感器,可以获取全参数Stokes矢量,进而解算出目标的AOP、DOP、LDOP和CDOP等信息。基于C++语言和OpenCV库,采用MFC架构开发了上位机程序,实现了目标偏振信息的实时显示。在最大分辨率下,视频流的刷新率为3frame/s,基本满足了实时探测的需要。对晴朗天气条件下天空偏振场图进行了实际探测,实验过程中探测器性能稳定,天空偏振场图与瑞利散射模型具有较高的一致性,太阳子午线动态识别误差为0.01°~0.23°,初步证明了探测器的可靠性,为后续工作奠定了基础。

穿戴式心电及心振信号监测系统的研制

目的心脏的电活动及机械活动对于研究心脏的生理功能和病理改变具有重要作用,为此本研究研制了一套心电(electrocardiogram,ECG)及心振(seismocardiogram,SCG)信号同步监测系统。方法采用单导联方式进行心电检测,通过测量胸廓皮肤表面的三轴线加速度和三轴角速度来获取心振信号,以ARM Cotex-M3内核的低功耗微处理器STM32作为主控芯片将数据存储至SD卡,或通过低功耗蓝牙将采集的数据发送至手机端上位机并进行数据处理及波形显示。结果对人体进行测量以获取ECG及SCG信号,结果表明系统能够实时采集、传输、显示具有较高信噪比的心电和心振信号,并能实现信号的长期离线记录。结论该系统具有便携、操作简单的特点,能够长期稳定工作,为下一步分析心脏的电活动与机械活动之间的耦联关系奠定了基础。

Infrared polarization image fusion based on combination of NSST and improved PCA

In view of the problem that current mainstream fusion method of infrared polarization image—Multiscale Geometry Analysis method only focuses on a certain characteristic to image representation.And spatial domain fusion method,Principal Component Analysis(PCA)method has the shortcoming of losing small target,this paper presents a new fusion method of infrared polarization images based on combination of Nonsubsampled Shearlet Transformation(NSST)and improved PCA.This method can make full use of the effectiveness to image details expressed by NSST and the characteristics that PCA can highlight the main features of images.The combination of the two methods can integrate the complementary features of themselves to retain features of targets and image details fully.Firstly,intensity and polarization images are decomposed into low frequency and high frequency components with different directions by NSST.Secondly,the low frequency components are fused with improved PCA,while the high frequency components are fused by joint decision making rule with local energy and local variance.Finally,the fused image is reconstructed with the inverse NSST to obtain the final fused image of infrared polarization.The experiment results show that the method proposed has higher advantages than other methods in terms of detail preservation and visual effect.

UG参数化建模在发电机部件设计上的应用

传统模式设计过程中,发电机的转子扭振图需要设计者根据电算单中相关参数计算出转子的转动惯量和重量等参数,最后输入到二维CAD软件设计。整个设计过程人为操作易出错,而且效率低。基于UG软件二次开发进行转轴参数化建模,更新原有设计模式,针对转子图进行自动化设计模块的开发。提高产品标准化程度,缩短设计时间,缩减成本,提升产品市场竞争力。

Petrophysical evaluation and its application to AVO based on conventional and CMR-MDT logs

Conventional loggings provide the essential data for AVO （Amplitude-Versus- Offset） analysis in rock physics, which can build a bridge linking petrophysics and seismic data. However, if some complex fluid systems, such as serious fluid invasion to formation, low resistivity response or complicated water salinity etc. exist in reservoirs, the conventional logs may fail to provide quality data, leading to calculated errors for elastic properties so worse that the AVO results cannot match the seismic data. To overcome such difficulties in Tertiary reservoirs of Bohai Gulf in China, we utilized both conventional logs and CMR- MDT tool （Combinable Magnetic Resonance and Modular Formation Dynamics Tester） to perform formation evaluation and reservoir descriptions. Our research proposes, it allows petrophysicists to acquire reservoir parameters （e.g. porosity, permeability, water saturation, bound fluids and pore pressure etc）, and then these results to combine with core analysis based on laboratory＇s measurements to carry out a further rock physics study and AVO analysis in seismic domain.

基于卷积神经网络的滚动轴承故障诊断研究

针对滚动轴承故障特征难以准确表征的问题,基于轴承振动信号具有短时平稳性的特点,提出对轴承振动信号进行分帧、加窗、DFT、图像编码等处理后构建表征轴承故障的振动信号振谱图。设计用于滚动轴承故障诊断的深度卷积神经网络,采用已知故障模式的轴承振动信号振谱图及其对应的故障标签对网络进行1训练。基于此方法,以美国凯斯西储大学公开的滚动轴承故障诊断实测振动信号为对象进行故障建模与识别,结果表明:所识别的轴承故障准确率达到100%,获得了很高的故障诊断精度。

RIGHT INFERIOR FRONTAL GYRUS PROCESSING OF VISUAL EROTIC INFORMATION BASED ON fMRI

Visually-induced erotic arousal evoked by pornographic visual stimuli, such as films or photographs, is a common occurrence in human behavior. The brain activation associated with visual erotic stimuli in heterosexual right handed females is studied. Functional magnetic resonance imaging is used to investigate 15 female partici- panterotic arousal induced by visual stimuli in film and picture forms, respectively, performing three or more times during their menstrual cycle on a 3.0T magnetic resonance imaging scanner. There is activation of a set of bilateral brain areas, including the inferior lateral occipital cortex, the anterior supramarginal gyrus, the parietal operculum cortex, the superior parietal lobules, the right inferior frontal gyrus, the cerebellum, the hypothalamus, the thalamus, the hippocampus, and the mid-brain. From different regions, the brain activation is observed and the inferior frontal gyrus has found to be task-independent. Furthermore, the right inferior frontal gyrus has more activation than the left inferior frontal gyrus. The result shows that the right inferior frontal gyrus plays an important role in pornographic information processing rather than being activated stimuli property specific. It is presented for the first time that the functional laterization of the inferior frontal gyrus is bi-directional rather than single （left） directional.

桔皮油中与发泡聚苯乙烯塑料相溶组分的分析

气相色谱法测定结果表明：桔皮提取物中有一绝对优势组分。通过红外光谱和核磁共振进一步协同确定，与聚苯乙烯具有良好相溶性的组分是(d)-柠烯，即d-limonene。

Strategy to differentiate autoimmune pancreatitis from pancreas cancer

Autoimmune pancreatitis (AIP) is a newly described entity of pancreatitis in which the pathogenesis appears to involve autoimmune mechanisms. Based on histological and immunohistochemical examinations of various organs of AIP patients, AIP appears to be a pancreatic lesion reflecting a systemic "IgG4-related sclerosing disease". Clinically, AIP patients and patients with pancreatic cancer share many features, such as preponderance of elderly males, frequent initial symptom of painless jaundice, development of new-onset diabetes mellitus, and elevated levels of serum tumor markers. It is of uppermost importance not to misdiagnose AIP as pancreatic cancer. Since there is currently no diagnostic serological marker for AIP, and approach to the pancreas for histological examination is generally difficult, AIP is diagnosed using a combination of clinical, serological, morphological, and histopathological features. Findings suggesting AIP rather than pancreatic cancer include:fluctuating obstructive jaundice; elevated serum IgG4 levels; diffuse enlargement of the pancreas; delayed en- hancement of the enlarged pancreas and presence of a capsule-like rim on dynamic computed tomography; low apparent diffusion coefficient values on diffusion-weighted magnetic resonance image; irregular narrowing of the main pancreatic duct on endoscopic retrograde cholangiopancreatography; less upstream dilatation of the main pancreatic duct on magnetic resonance cholangiopancreatography, presence of other organ involvement such as bilateral salivary gland swelling, retroperitoneal fibrosis and hilar or intrahepatic sclerosing cholangitis; negative work-up for malignancy including endoscopic ultrasound-guided fine needle aspiration; and steroid responsiveness. Since AIP responds dramatically to steroid therapy, accurate diagnosis of AIP can avoid unnecessary laparotomy or pancreatic resection.

机房地线引起的干扰及其抑制方法

从地环路干扰和公共地线阻抗干扰两方面分析了地线干扰的成因与机理，提出了抑制地线环路干扰、减小公共地线阻抗耦合等抑制地线干扰的方法。

Application of Preoperative CT/MRI Image Fusion in Target Positioning for Deep Brain Stimulation

Objective To explore the efficacy of target positioning by preoperative CT/MRI image fusion technique in deep brain stimulation.Methods We retrospectively analyzed the clinical data and images of 79 cases(68 with Parkinson's disease,11 with dystonia) who received preoperative CT/MRI image fusion in target positioning of subthalamic nucleus in deep brain stimulation.Deviation of implanted electrodes from the target nucleus of each patient were measured.Neurological evaluations of each patient before and after the treatment were performed and compared.Complications of the positioning and treatment were recorded.Results The mean deviations of the electrodes implanted on X,Y,and Z axis were 0.5 mm,0.6 mm,and 0.6 mm,respectively.Postoperative neurologic evaluations scores of unified Parkinson's disease rating scale(UPDRS) for Parkinson's disease and Burke-Fahn-Marsden Dystonia Rating Scale(BFMDRS) for dystonia patients improved significantly compared to the preoperative scores(P<0.001); Complications occurred in 10.1%(8/79) patients,and main side effects were dysarthria and diplopia.Conclusion Target positioning by preoperative CT/MRI image fusion technique in deep brain stimulation has high accuracy and good clinical outcomes.

METABOLIC ABNORMALITIES IN MESIAL TEMPORAL LOBE EPILEPSY PATIENTS DEPICTED BY PROTON MR SPECTROSCOPY USING A 3.0T MR SCANNER

Objective To evaluate metabolic abnormalities in patients with mesial temporal lobe epilepsy （MTLE） with proton magnetic resonance spectroscopy （MRS） using a 3.0T MR scanner. Methods Sixty-three patients （32 women and 31 men） with diagnosed MTLE underwent diagnostic MR imaging （MRI） and proton MRS using a 3.0T MR scanner. The clinical history and interictal epileptiform discharges （IEDs） were recorded. Sixteen healthy volunteers served as control. The results of proton MRS were compared with the findings of electroencephalogram and structural MRI findings. Results Twenty-seven of the 63 patients with MTLE showed unilateral hippocampal sclerosis, and 9 showed bilateral hippocampal sclerosis. The concentration ratio of N-acytelaspartate （NAA） / [ creatine （ Cr ） ＋ choline （Cho） ] in the hippocampal region of MTLE patients （0. 64±0. 07） was significantly lower than control （0. 80±0. 05, P = 0.023）. In the patients with unilateral hippocampal sclerosis, NAA/（Cr ＋ Cho） in the hippocampal region ipsilateral to the sclerotic hippocampus （0.56±0.06） was significantly lower than the ratio in the contralateral hippocampal region （0.69±0.07, P 〈 0. 001 ）. There was significant difference in hippocampal NAA/（ Cr ＋ Cho） between the refractory patients and the non-refractory patients （0. 64±0. 05 vs.0.71±0. 07, P =0. 04）. Forty-five patients were lateralized by IEDs, while 49 patients were lateralized by metabolite ratio. And lateralization determined by proton MRS and IEDs was concordant in 33 patients. Conclusions MRS as a noninvasive tool adds helpful metabolite information to routine MRI in evaluation of MTLE. The method is well established and should be a routine clinical application in the investigation of epilepsy.

Adaptive polarization i mage fusion based on regional energy dynamic weighted average

According to the principle of polarization imaging and the relation between Stokes parameters and the degree of linear polarization, there are much redundant and complementary information in polarized images. Since man-made objects and natural objects can be easily distinguished in images of degree of linear polarization and images of Stokes parameters contain rich detailed information of the scene, the clutters in the images can be removed efficiently while the detailed information can be maintained by combining these images. An algorithm of adaptive polarization image fusion based on regional energy dynamic weighted average is proposed in this paper to combine these images. Through an experiment and simulations,most clutters are removed by this algorithm. The fusion method is used for different light conditions in simulation, and the influence of lighting conditions on the fusion results is analyzed.

3.0-Tesla:OPPORTUNITIES AND CHALLENGES

With the development of magnetic resonance （MR） technology, the concern is focused on molecular and physiological imaging besides structural information. Ultra high field MR scanner shows great superiority. 3.0-T MR scanners provide almost two-fold signal-to-noise ratio （SNR） compared with a standard 1.5-T MR scanner. The higher baseline SNR can be converted into a variety of alternative benefits. There are still some other changes brought about by 3.0-T, such as higher sensitivity to motion, susceptibility effect, more difference in resonant frequency among different metabohies, and so on. These features may be a double-edged sword in structural and functional imaging. But with the ceaseless progress of the technology and gains in experience, 3.0-T systems will provide more information and show more advantages.

MRI Manif estions Correlate with Survival of Glioblastoma Multiforme Patients

Objective To identify the correlation between magnetic resonance manifestation and survival of patients with glioblastoma lnultiforme （GBM）, Methods The magnetic resonance imaging （MRI） images of 30 glioblastoma patients were collected. Imaging features including degrees of contrasted area, edema surrounding the tumor; and intensity in T2-weighted imaging were selected to determine their correlation with patient survival. The relationship between imaging and survival time was studied using SPSS 19.0 software. Kaplan- Meier survival analysis and log-rank test were used to compare the survival curves. Results Patients with 〈5% contrasted enhancement area of tumor had longer overall survival （OS） than those with 〉5% contrasted enhancement area of tumor. Patients without edema surrounding the tumor had longer OS than those with edema. Patients with tumor of hyperintensity and/or isointensity in T2-weighted imaging had longer OS than those with hyperintensity and/or isointensity and hypointensity. Conclusions Some MR imaging features including degrees of contrasted area, edema surrounding the tumor, and intensity in T2- weighted imaging are correlated with the survival of patients with GBM. These features can serve as prognostic indicators for GBM patients.

An adaptive fuzzy filter for coding artifacts removal in video and image

This paper proposes a new adaptive post-filtering algorithm to remove coding artifacts in block-based video coder. The proposed method concentrates on blocking and ringing artifacts removal. For de-blocking, the blocking strength is identified to determine the filtering range, and the maximum quantization parameter of the image is used to adapt the 1D fuzzy filter. For de-ringing, besides the edge detection, a complementary ringing detection method is proposed to locate the neglected ringing blocks, and the gradient threshold is adopted to adjust the parameter of 2D fuzzy filter. Experiments are performed on the MPEG-4 sequences. Compared with other methods, the proposed one achieves better detail preservation and artifacts removal performance with lower computational cost.

MRI of gastric carcinoma:Results of T and N-staging in an in vitro study

AIM： To determine the accuracy of 1.5-T magnetic resonance imaging （MRI） in the evaluation of gastric wall invasion and perigastric lymph node metastasis in gastric adenocarcinoma.METHODS： Twenty resected gastric specimens containing 20 tumors were studied with a 1.5-T MR system using a commercial head surface coil. MR scanning was performed with a T1 weighted image （TR/TE = 500/20）, and a T2 weighted image （TR/TE = 2500/90）. MR findings were compared with pathologic findings.RESULTS： A T1-weighted image demonstrated three layers in the normal gastric wall. All of the gastric tumors were well demonstrated by lesions and location. In a MRI findings of gastric wall invasion, there was 1 case of T1, 7 of T2, 11 of T3. Pathologic results of resected specimens included 3 cases of pT1, 4 of pT2, and 12 of pT3. The accuracy of T staging with MRI was 74% （14 of 19）. MRI findings of lymph node metastasis included 6 cases of NO, 13 cases of N1. The accuracy of the N staging with MRI was 47% （9 of 19）.CONCLUSION： MRI has a high diagnostic accuracy in the evaluation of the T staging of gastric cancerin vitro and thus potentially enables preoperative histopathologic staging.