High-precision automatic measurement of two-dimensional geometric features based on machine vision

To realize high-precision automatic measurement of two-dimensional geometric features on parts, a cooperative measurement system based on machine vision is constructed. Its hardware structure, functional composition and working principle are introduced. The mapping relationship between the feature image coordinates and the measuring space coordinates is established. The method of measuring path planning of small field of view （FOV） images is proposed. With the cooperation of the panoramic image of the object to be measured, the small FOV images with high object plane resolution are acquired automatically. Then, the auxiliary measuring characteristics are constructed and the parameters of the features to be measured are automatically extracted. Experimental results show that the absolute value of relative error is less than 0. 03% when applying the cooperative measurement system to gauge the hole distance of 100 mm nominal size. When the object plane resolving power of the small FOV images is 16 times that of the large FOV image, the measurement accuracy of small FOV images is improved by 14 times compared with the large FOV image. It is suitable for high-precision automatic measurement of two-dimensional complex geometric features distributed on large scale parts.

浅谈高三物理第一轮复习学法指导

高三复习要高效，很大程度上取决于实用的、良好的学习方法。教师在复习过程中应该倍加注重学习方法的指导。本文从具体操作层面介绍了几点有效的高三一轮复习学习方法。。

Contrast between 2D inversion and 3D inversion based on 2D high-density resistivity data

The 2D data processing adopted by the high-density resistivity method regards the geological structures as two degrees, which makes the results of the 2D data inversion only an approximate interpretation;the accuracy and effect can not meet the precise requirement of the inversion. Two typical models of the geological bodies were designed, and forward calculation was carried out using finite element method. The forward-modeled profiles were obtained. 1% Gaussian random error was added in the forward models and then 2D and 3D inversions using a high-density resistivity method were undertaken to realistically simulate field data and analyze the sensitivity of the 2D and 3D inversion algorithms to noise. Contrast between the 2D and 3D inversion results of least squares inversion shows that two inversion results of high-density resistivity method all can basically reflect the spatial position of an anomalous body. However, the 3D inversion can more effectively eliminate the influence of interference from Gaussian random error and better reflect the distribution of resistivity in the anomalous bodies. Overall, the 3D inversion was better than 2D inversion in terms of embodying anomalous body positions, morphology and resistivity properties.

First-line endoscopic treatment with over-the-scope clips significantly improves the primary failure and rebleeding rates in high-risk gastrointestinal bleeding: A single-center experience with 100 cases

AIM To evaluate rebleeding, primary failure(PF) and mortality of patients in whom over-the-scope clips(OTSCs) were used as first-line and second-line endoscopic treatment(FLET, SLET) of upper and lower gastrointestinal bleeding(UGIB, LGIB).METHODS A retrospective analysis of a prospectively collected database identified all patients with UGIB and LGIB in a tertiary endoscopic referral center of the University of Freiburg, Germany, from 04-2012 to 05-2016(n= 93) who underwent FLET and SLET with OTSCs. The complete Rockall risk scores were calculated from patients with UGIB. The scores were categorized as < or ≥ 7 and were compared with the original Rockall data. Differences between FLET and SLET were calculated. Univariate and multivariate analysis were performed to evaluate the factors that influenced rebleeding after OTSC placement.RESULTS Primary hemostasis and clinical success of bleeding lesions(without rebleeding) was achieved in 88/100(88%) and 78/100(78%), respectively. PF was significantly lower when OTSCs were applied as FLET compared to SLET(4.9% vs 23%, P = 0.008). In multivariate analysis, patients who had OTSC placement as SLET had a significantly higher rebleeding risk compared to those who had FLET(OR 5.3; P = 0.008). Patients with Rockall risk scores ≥ 7 had a significantly higher in-hospital mortality compared to those with scores < 7(35% vs 10%, P = 0.034). No significant differences were observed in patients with scores < or ≥ 7 in rebleeding and rebleeding-associated mortality.CONCLUSION Our data show for the first time that FLET with OTSC might be the best predictor to successfully prevent rebleeding of gastrointestinal bleeding compared to SLET. The type of treatment determines the success of primary hemostasis or primary failure.

High dimension feature extraction based visualized SOM fault diagnosis method and its application in p-xylene oxidation process

Purified terephthalic acid(PTA) is an important chemical raw material. P-xylene(PX) is transformed to terephthalic acid(TA) through oxidation process and TA is refined to produce PTA. The PX oxidation reaction is a complex process involving three-phase reaction of gas, liquid and solid. To monitor the process and to improve the product quality, as well as to visualize the fault type clearly, a fault diagnosis method based on selforganizing map(SOM) and high dimensional feature extraction method, local tangent space alignment(LTSA),is proposed. In this method, LTSA can reduce the dimension and keep the topology information simultaneously,and SOM distinguishes various states on the output map. Monitoring results of PX oxidation reaction process indicate that the LTSA–SOM can well detect and visualize the fault type.

An Interactive Point-Picking Method by Combining 2D and 3D Views of a Slice Geometry

Interactive picking is a fundamental task for processing and images. Combining two-dimensional （2D） and three-dimensional digital graphics （3D） views is an important trend in processing medical sliced-geometries. With the goal of accurately picking points in sliced-geometries, we present a method to pick points interactively by combining 2D and 3D views of sliced-geometries. Four view windows are constructed to render sliced-geometries using medical imaging interaction toolkit （MITK）： three for 2D slices parallel to the XY, YZ, and XZ planes and one for surface rendering. Points picked in a view window can be rendered and modified in any window. After a point is picked, it is immediately converted into a world coordinate and stored. Points are only rendered and modified based on their world coordinates. This picking method can be used for fitting, observing, and measuring local regions. This method can also be used for interactive segments. Our experiment shows that the picking method is accurate and has a real-time picking effect.

Effect of endobronchial blocker tube in the pulmonary carcinoma with video-assisted thoracic surgery

Objective:The aim of this study was to observe the effect of endobronchial blocker tube in the pulmonary carcinoma with video-assisted thoracic surgery.Methods:Forty patients of pulmonary carcinoma with video-assisted thoracic surgery were randomly assigned into two groups with twenty cases each:endobronchial blocker tube group(group 1) and double-lumen endobronchial tube group(group 2).After anesthesia was induced,in group 1,single lumen tube was intubated at first,and then endobronchial blocker tube intubated to left or right primary bronchus under the guidance of fiber-optic bronchoscope according to operational necessary,injected 2-4 mL air to blocker balloon and blocker one lateral primary bronchus for one-lung ventilation necessarily;while in group 2,the position of double-lumen endobronchial tube was confirmed with fiber-optic bronchoscope after intubation.Blood samples were collected before anesthesia induction,double lumen ventilation,at the one-lung ventilation of 5 min,30 min,60 min,120 min and 180 min,SBP,DBP,HR,SpO2,partial pressure of end tidal carbon dioxide(PetCO2),pH,PaO2,PaCO2,PaO2/FiO2 were recorded.Results:Forty cases' intubations were all successful.There were no differences in SBP,DBP,HR,SpO2,PetCO2,pH,PaCO2 between two groups in different points(P > 0.05).Paw in group 1 was lower than group 2,PaO2 and PaO2/FiO2 in group 1 was higher than group 2 in the one lung ventilation of 5 min,30 min,60 min,120 min and 180 min.Conclusion:The endobronchial blocker tube can meet the request of video-assisted thoracic surgery,with the special advantages of simple insertion,lower airway and better oxygenation.Endobronchial blocker tube offer a new way for one-lung ventilation in the pulmonary carcinoma with video-assisted thoracic surgery.

Laparoscopic and endoscopic co-operative surgery for nonampullary duodenal tumors

AIM To assess the safety and feasibility of laparoscopic and endoscopic co-operative surgery(LECS) for early nonampullary duodenal tumors.METHODS Twelve patients with a non-ampullary duodenal tumor underwent LECS at our hospital. One patient had two mucosal lesions in the duodenum. The indication for this procedure was the presence of duodenal tumors with a low risk for lymph node metastasis. In particular, the tumors included small(less than 10 mm) submucosal tumors(SMT) and epithelial mucosal tumors, such as mucosal cancers or large mucosal adenomas with malignant suspicion. The LECS procedures, such as full-thickness dissection for SMT and laparoscopic reinforcement after endoscopic submucosal dissection(ESD) for epithelial tumors, were performed for the 13 early duodenal lesions in 12 patients. Here we present the short-term outcomes and evaluate the safety and feasibility of this new technique.RESULTS Two SMT-like lesions and eleven superficial epithelial tumor-like lesions were observed. Seven and Six lesions were located in the second and third parts of the duodenum, respectively. All lesions were successfully resected en bloc. The defect in the duodenal wall was manually sutured after resection of the duodenal SMT. For epithelial duodenal tumors, the ulcer bed was laparoscopically reinforced via manual suturing after ESD. Intraoperative perforation occurred in two out of eleven epithelial tumor-like lesions during ESD; however, they were successfully laparoscopically repaired. The median operative time and intraoperative estimated blood loss were 322 min and 0 mL, respectively. Histological examination of the tumors revealed one adenoma with moderate atypia, ten adenocarcinomas, and two neuroendocrine tumors. No severe postoperative complications(Clavien-Dindo classification grade Ⅲ or higher) were reported in this series, but minor leakage secondary to pancreatic fistula occurred in one patient.CONCLUSION LECS can be a safe and minimally invasive treatment option for non-ampullary early duodenal tumors.

Low Distortion 1.31μm AlGaInAs/InP MQW DFB Laser Module for CATV Systems

A high power and low distortion 1.31 μm AlGaInAs/InP multiquantum well distributed feedback laser diode (MQW DFB LD) with RWG structure has been developed by MOCVD technique. The fiber output power of butterfly packaged module with optic isolator P f is more than 10 mW, threshold current is in the range of (13～20) mA, slope efficiency, E s>0.30 W/A and side mode suppression ratio, R S,M,S >35 dB. The composite second order, O C,S <-61 dBc and composite triple beat, B C,T <-65 dBc are obtained by test frequencies of (45～550) MHz with 60 PAL channels. In the test conditions the carrier to noise ratio, R C,N >51 dB.

Virtual Reality and Visual Simulation Technology in Platform Construction with Four Bucket Foundations Based on Secondary Development of Vega

The platform with bucket foundations can penetrate and migrate by underpressure/positive pressure technique caused by pumping water out/in the bucket. However, the construction process of bucket foundations cannot be clearly observed and effectively controlled due to the special nature of sea environment. By using an advanced simulation development tool of Multigen Creator, the visual construction simulation program for the platform with bucket foundations was developed to set up the virtual reality system with interaction control and observation in every view angle based on the secondary development technology of Vega platform. The application results show that the method is feasible and effective by simulating the whole construction process for the platform with four bucket foundations.

The anesthesia analysis of the conversion video-assisted thoracic surgery to thoracotomy in pulmonary carcinoma

Objective： The aim of this study was to anesthesia analyse the factors of conversing video-assisted thoracic surgery to thoracectomy in pulmonary carcinoma. Methods： Double-lumen tube bronchial catheter intubation and interstitial positive pressure ventilation （IPPV） were used in all patients with video-assisted thoracic surgery after fast-speed venous induced anesthesia. IPPV, positive expiratory pressure （PEEP） and continuous positive airway pressure （CPAP） in collapse lobes of lung were used in one lung ventilation, and ventilation parameters were adjusted. Results： Two hundred and fifity- two patients double-lumen bronchial tube intubation used by fiberscope was located very well. The level of oxygen saturation of blood （Sp02）, end.tidal carbon dioxide pressure （PETCO2） could be maintained normal. 5 cases were forced to converse video-assisted thoracic surgery to thoracotomy because of 2 cases pulmonary adhesion, 2 cases severe pulmonary dysfunction and 1 case abnormal anatomy respectively. Conclusion： Long one lung ventilation such as pulmonary adhesion, severe pulmonary dysfunction and abnormal anatomy should be considered to be relative contraindication.

A retinal blood vessel extraction algorithm based on CART decision tree and improved AdaBoost

This paper presents a supervised learning algorithm for retinal vascular segmentation based on classification and regression tree (CART) algorithm and improved adptive bosting (AdaBoost). Local binary patterns (LBP) texture features and local features are extracted by extracting,reversing,dilating and enhancing the green components of retinal images to construct a 17-dimensional feature vector. A dataset is constructed by using the feature vector and the data manually marked by the experts. The feature is used to generate CART binary tree for nodes,where CART binary tree is as the AdaBoost weak classifier,and AdaBoost is improved by adding some re-judgment functions to form a strong classifier. The proposed algorithm is simulated on the digital retinal images for vessel extraction (DRIVE). The experimental results show that the proposed algorithm has higher segmentation accuracy for blood vessels,and the result basically contains complete blood vessel details. Moreover,the segmented blood vessel tree has good connectivity,which basically reflects the distribution trend of blood vessels. Compared with the traditional AdaBoost classification algorithm and the support vector machine (SVM) based classification algorithm,the proposed algorithm has higher average accuracy and reliability index,which is similar to the segmentation results of the state-of-the-art segmentation algorithm.

Deterritorializing the Nation： Deleuzian Time, Space and Narrative in the Video Art of Lia Lapithi Shukuroglou

The purpose of this paper is to engage with Gilles Deleuze＇s work on time and space in cinema as a theoretical trajectory for exploring the video art of Lia Lapithi Shukuroglou. In Cinema 2： The Time-Image （1989）, Deleuze argues that post-Second World War cinema has been shaped by a historical transformation compelling it to create new signs and images. Centering on the post-war landscape of Cyprus in 1974, the moment of ＂historical transformation＂ in Deleuze is transposed to this national context; examining Lapithi＇s response to the crisis of historical time in its relation to physical spaces. It negotiates a contextualized reading of three videos and argues that they manifest Deleuzian ＂time-images＂. These texts react to the territorialization of real spaces by deterritorializing official national history. Using Martin Jones＇ study, Deleuze, cinema and national identity： Narrative time in national contexts （2006） Lapithi＇s time-images are interpreted as ＂unruly＂ as they resist a linear narrative and destabilize public time. Contrary to Martin Jones＇s view that time-images constitute a temporary deviation from flowing national time, the author argues that Lapithi excavates alternative temporalities in perpetuity; whilst proposing that in the context of Cyprus the deterritorialization of space by time postpones the nation＇s identity.

Entropy Correction for Cosmological Horizon of Schwarzschild-de Sitter Black Holes

In this paper, we first calculate the emission rate of the massive particles＇ de Sitter tunneling across the cosmological horizon of Schwarzschild-de Sitter black holes to the second order accuracy. Then, by assuming the emission process satisfies an underlying unitary theory, we have obtained the corrected entropy for cosmological horizon. Finally, a discussion about the de Sitter tunneling is presented.

A DESCRIPTION METHOD FOR ARBITRARILY SHAPED AND SIZED GRANULES IN 2D IMAGE

An alternative method is proposed in this letter for describing the arbitrary shape and size for granules in 2D image.After image binarization, the edge points on contour are detected, by which the centroid of the shape in question is sought using the moment calculation.Using Principal Component Analysis(PCA), the major and minor diameters are computed.Based on the signature curve-fitting, the first-order derivative is taken so as to seek all the characteristic vertices.By connecting the vertices found, the simplified polygon is formed and utilized for shape and size descriptive purposes.The developed algorithm is run on two given real particle images, and the execution results indicate that the computed parameters can technically well describe the shape and size for the original particles, being able to provide a ready-to-use database for machine vision system to perform related data processing tasks.

Influence of muscle regions of meridians needling method combined with auricular point sticking on pain and range of motion in patients with chronic nonspecific low back pain

Objective:To observe the effects of muscle regions of meridians needling method combined with auricular point sticking on pain and lumbar range of motion in patients with chronic nonspecific low back pain.Methods:A total of 100 patients with chronic nonspecific low back pain were randomly divided into a control group and an observation group,with 50 patients in each group.Both groups received auricular point sticking treatment,while the control group received additional conventional acupuncture treatment,and the observation group received additional muscle regions of meridians needling method.The total effective rate of the two groups was compared after 4 weeks of treatment.Before treatment and after 1 week and 4 weeks of treatment,the visual analog scale(VAS)score was used to assess the degree of low back pain,and the modified-modified Schober(MMS)score was used to evaluate the lumbar range of motion.Results:There was statistical significance in comparing the total effective rate between the two groups(P<0.01).During the treatment process,as the number of treatments increased,the VAS score gradually decreased,and the MMS score gradually increased in both groups.After 1 week and 4 weeks of treatment,the VAS score in the observation group was lower than that in the control group(P<0.01),and the MMS score in the observation group was higher than that in the control group(P<0.01).During the treatment period,no serious adverse reactions occurred in either group.Conclusion:Based on auricular point sticking treatment,muscle regions of meridians needling method is more effective than conventional acupuncture in treating chronic nonspecific low back pain since it is able to significantly reduce the pain and improve the lumbar range of motion.

Effects of organic solvents on two retinal pigment epithelial lipofuscin fluorophores, A2E and all-trans-retinal dimer

Gene and drug therapies are being developed to al eviate vision loss in patients with Stargardt’s disease and age-related macular degeneration （AMD）. To evaluate the therapeutic effects of these treatments, organic sol-vents are routinely used to extract and quantify bisretinoid lipofuscin constituents, such as N-retinylidene-N-retinyl-ethanolamine （A2E） and all-trans-retinal dimer （ATR-dimer）. By high-performance liquid chromatography （HPLC）, we found that A2E and ATR-dimer were both altered by tetrahydrofuran （THF） and chloroform, but were stable in dimethyl sulfoxide （DMSO） or methanol （MeOH）. In addition, cyclohexane and ethanol （EtOH） did not alter ATR-dimer, whereas an alteration of A2E occurred in EtOH. On the basis of these findings, we designed processes II-IV, generated by modifications of process I, a routine method to measure bisretinoid compounds in vivo. Extra amounts of either ATR-dimer or A2E in mouse eyecups were released by processes II-IV versus process I. Efforts to clarify the effects of organic solvents on lipofuscin pigments are important because such studies can guide the handling of these fluoro-phores in related experiments.

Squint-mode InISAR imaging based on nonlinear least square and coordinates transform

Aiming at the interferometric inverse synthetic aperture radar （InlSAR） imaging in the presence of squint, we investigate the influence of squint on the InlSAR imaging. First, coupling of the squint additive phase and the target azimuth/altitude coordinates to be solved may make the solution more difficult. Second, the squint angle may lead to estimation error of the vertical coordinates and distortion of the ultimate image. Traditional InlSAR imaging algorithms can not solve the above two problems effectively, so we propose a new method which combines the nonlinear least square （NLS） and coordinates transform （CT） to estimate the target coordinates, and a three-dimensional （3-D） image consistent with the real target is obtained accordingly. Simulations show that the proposed method is effective for the squint-mode InlSAR imaging.

Experimental and numerical investigation of unsteady cavitating flows through a 2D hydrofoil

In the present study, firstly, the unsteady cavitating flows around a hydrofoil are studied based on the flow visualization and detail velocity measurement, a high-speed video camera is used to visualize the flow structures, and a particle image velocimetry （PIV） technique is applied to the measurement of the time-averaged and instantaneous velocity and vorticity fields. The results show that the unsteadiness of mass transfer process between the vapor and the two-phase regions is substantial, a self-oscillatory behavior of the whole sheet cavitation is obtained, with large length fluctuations and vapor cloud shedding, and also the cavitation structure depends on the interaction of the water-vapor mixture and the periodic vortex shedding. The main purpose of this experimental study is to offer information for validating computational models, and shed light on the unsteady multiphase transport process of cavitating flows. Furthermore, with an emphasis on the dynamics of the attached turbulent cavitating flows, a filter-based model （FBM） is derived from the k-6 two-equation model, a conditional averaging method aimed at improving unsteady simulation is applied to computation. In comparison to the standard k-ε model, overall, the filter-based model is shown to improve the predictive capability considerably.

Pore-scale visualization on a depressurization-induced CO2 exsolution

The pore-scale behavior of the exsolved CO_2 phase during the depressurization process in CO_2 geological storage was investigated.The reservoir pressure decreases when the injection stops or when a leaking event or fluid extraction occurs.The exsolution characteristics of CO_2 affect the migration and fate of CO_2 in the storage site significantly.Here,a micromodel experimental system that can accommodate a large pressure variation provides a physical model with homogeneous porous media to dynamically visualize the nucleation and growth of exsolved CO_2 bubbles.The pressure decreased from 9.85 to 3.95 MPa at different temperatures and depressurization rates,and the behavior of CO_2 bubbles was recorded.At the pore-scale,the nuclei became observable when the CO_2 phase density was significantly reduced,and the pressure corresponding to this observation was slightly lower than that of the severe expansion pressure region.The lower temperature and faster depressurization rate produced more CO_2 nuclei.The exsolved CO_2 bubble preferentially grew into the pore body instead of the throat.The progress of smaller CO_2 bubbles merging into a larger CO_2 bubble was first captured,which validated the existence of the Ostwald ripening mechanism.The dispersed CO_2 phase after exsolution shows similarity with the residually trapped CO_2.This observation is consistent with the low mobility and high residual trapping ratio of exsolved CO_2 measured in the core-scale measurement,which is considered to be a self-sealing mechanism during depressurization process in CO_2 geological storage.