• Title/Summary/Keyword: Lu's method

Search Result 167, Processing Time 0.025 seconds

Adaptable Center Detection of a Laser Line with a Normalization Approach using Hessian-matrix Eigenvalues

  • Xu, Guan;Sun, Lina;Li, Xiaotao;Su, Jian;Hao, Zhaobing;Lu, Xue
    • Journal of the Optical Society of Korea
    • /
    • v.18 no.4
    • /
    • pp.317-329
    • /
    • 2014
  • In vision measurement systems based on structured light, the key point of detection precision is to determine accurately the central position of the projected laser line in the image. The purpose of this research is to extract laser line centers based on a decision function generated to distinguish the real centers from candidate points with a high recognition rate. First, preprocessing of an image adopting a difference image method is conducted to realize image segmentation of the laser line. Second, the feature points in an integral pixel level are selected as the initiating light line centers by the eigenvalues of the Hessian matrix. Third, according to the light intensity distribution of a laser line obeying a Gaussian distribution in transverse section and a constant distribution in longitudinal section, a normalized model of Hessian matrix eigenvalues for the candidate centers of the laser line is presented to balance reasonably the two eigenvalues that indicate the variation tendencies of the second-order partial derivatives of the Gaussian function and constant function, respectively. The proposed model integrates a Gaussian recognition function and a sinusoidal recognition function. The Gaussian recognition function estimates the characteristic that one eigenvalue approaches zero, and enhances the sensitivity of the decision function to that characteristic, which corresponds to the longitudinal direction of the laser line. The sinusoidal recognition function evaluates the feature that the other eigenvalue is negative with a large absolute value, making the decision function more sensitive to that feature, which is related to the transverse direction of the laser line. In the proposed model the decision function is weighted for higher values to the real centers synthetically, considering the properties in the longitudinal and transverse directions of the laser line. Moreover, this method provides a decision value from 0 to 1 for arbitrary candidate centers, which yields a normalized measure for different laser lines in different images. The normalized results of pixels close to 1 are determined to be the real centers by progressive scanning of the image columns. Finally, the zero point of a second-order Taylor expansion in the eigenvector's direction is employed to refine further the extraction results of the central points at the subpixel level. The experimental results show that the method based on this normalization model accurately extracts the coordinates of laser line centers and obtains a higher recognition rate in two group experiments.

Determination of Reactivities by Molecular Orbital Theory (V). Sigma Molecular Orbital Treatment of $S_N$ Reactivities of Alkylchlorides. (화학반응성의 분자궤도론적 연구 (제5보). 염화알킬의 친핵성치환 반응성에 대한 시그마 분자궤도론적 연구)

  • Ikchoon Lee;Bon-Su Lee;Kwang-Su Kim
    • Journal of the Korean Chemical Society
    • /
    • v.17 no.2
    • /
    • pp.95-104
    • /
    • 1973
  • Ground electronic structures and SNreactivities of a series of alkylchlorides (methyl,ethyl, iso-propyl, trans n-butyl, sec-butyl, tert-butylchloride) have been studied using approximate $({\sigma}-MO)$ method, such as EHT and CNDO/2. It was found that CNDO/2 gives better results for the systems such as alkylchlorides whose structural differences are not remarkable, in comparison with EHT method. According to CNDO/2 results, calculated dipole moments for alkylchlorides are slightly higher than observed values, showing the order of primary < secondary < tertiary alkylchlorides. It was also found that highest occupied(HO) MO's are completely or nearly degenerate, and show relatively weak $\pi$-antibonding nature between$\alpha$-carbon and Cl atoms. Furthermore, the electrons in this MO are largely confined to Cl atom, and hence these behaves as likely as p-lone pair electrons of Cl atom. On the contrary, lowest unoccupied (LU) MO's show strong $\sigma$-antibonding nature between $\alpha$-carbon and Cl atoms whose electron clouds are directed along the C-Cl axis. It has been discussed that the$S_N2$ reactivities of alkylchlorides may largely be controlled by ${\sigma}^{\ast}$ LUMO, and the antibonding strength between $\alpha$-carbon and Cl atoms in this MO may become the measure of $S_N2$reactivity. The relationship between $S_N2$reactivity and C-Cl bond polarizability has also been discussed. It has been suggested that the unique structure factors determining $S_N1$reactivities may be $\pi$-antibonding strength between $\alpha$-carbon and Cl atoms in HOMO and C-Cl bond strength in ground state.

  • PDF

Isolation of Probiotic Piliated Lactobacillus rhamnosus Strains from Human Fecal Microbiota Using SpaA Antiserum-Based Colony Immunoblotting

  • Yang, Zhen-quan;Xue, Yu;Rao, Sheng-qi;Zhang, Mi;Gao, Lu;Yin, Yong-qi;Chen, Da-wei;Zhou, Xiao-hui;Jiao, Xin-an
    • Journal of Microbiology and Biotechnology
    • /
    • v.27 no.11
    • /
    • pp.1971-1982
    • /
    • 2017
  • Piliated Lactobacillus rhamnosus (pLR) strains possess higher adherent capacity than non-piliated strains. The objective of this study was to isolate and characterize probiotic pLR strains in human fecal samples. To this end, mouse polyclonal antiserum (anti-SpaA) against the recombinant pilus protein (SpaA) of L. rhamnosus strain GG (LGG) was prepared and tested for its reactivity and specificity. With the anti-SpaA, a method combining the de Man, Rogosa, and Sharpe (MRS) agar plating separation and colony immunoblotting (CIB) was developed to isolate pLR from 124 human fecal samples. The genetic and phenotypic characteristics of the resultant pLR isolates were compared by randomly amplified polymorphic DNA (RAPD) fingerprinting, and examination of adhesion to Caco-2 cells, hydrophobicity, autoaggregation, and in vitro gastrointestinal tolerance. Anti-SpaA specifically reacted with three pLR strains of 25 test strains, as assessed by western blotting, immunofluorescence flow cytometry, and immunoelectron microscopy (IEM) assays. The optimized MRS agar separation plus anti-SpaA-based CIB procedure could quantitatively detect $2.5{\times}10^3CFU/ml$ of pLR colonies spiked in $10^6CFU/ml$ of background bacteria. Eight pLR strains were identified in 124 human fecal samples, and were confirmed by 16S RNA gene sequencing and IEM identification. RAPD fingerprinting of the pLR strains revealed seven different patterns, of which only two isolates from infants showed the same RAPD profiles with LGG. Strain PLR06 was obtained with high adhesion and autoaggregation activities, hydrophobicity, and gastrointestinal tolerance. Anti-SpaA-based CIB is a rapid and inexpensive method for the preliminary screening of novel adherent L. rhamnosus strains for commercial purposes.

Multiple damage detection of maglev rail joints using time-frequency spectrogram and convolutional neural network

  • Wang, Su-Mei;Jiang, Gao-Feng;Ni, Yi-Qing;Lu, Yang;Lin, Guo-Bin;Pan, Hong-Liang;Xu, Jun-Qi;Hao, Shuo
    • Smart Structures and Systems
    • /
    • v.29 no.4
    • /
    • pp.625-640
    • /
    • 2022
  • Maglev rail joints are vital components serving as connections between the adjacent F-type rail sections in maglev guideway. Damage to maglev rail joints such as bolt looseness may result in rough suspension gap fluctuation, failure of suspension control, and even sudden clash between the electromagnets and F-type rail. The condition monitoring of maglev rail joints is therefore highly desirable to maintain safe operation of maglev. In this connection, an online damage detection approach based on three-dimensional (3D) convolutional neural network (CNN) and time-frequency characterization is developed for simultaneous detection of multiple damage of maglev rail joints in this paper. The training and testing data used for condition evaluation of maglev rail joints consist of two months of acceleration recordings, which were acquired in-situ from different rail joints by an integrated online monitoring system during a maglev train running on a test line. Short-time Fourier transform (STFT) method is applied to transform the raw monitoring data into time-frequency spectrograms (TFS). Three CNN architectures, i.e., small-sized CNN (S-CNN), middle-sized CNN (M-CNN), and large-sized CNN (L-CNN), are configured for trial calculation and the M-CNN model with excellent prediction accuracy and high computational efficiency is finally optioned for multiple damage detection of maglev rail joints. Results show that the rail joints in three different conditions (bolt-looseness-caused rail step, misalignment-caused lateral dislocation, and normal condition) are successfully identified by the proposed approach, even when using data collected from rail joints from which no data were used in the CNN training. The capability of the proposed method is further examined by using the data collected after the loosed bolts have been replaced. In addition, by comparison with the results of CNN using frequency spectrum and traditional neural network using TFS, the proposed TFS-CNN framework is proven more accurate and robust for multiple damage detection of maglev rail joints.

Predicting blast-induced ground vibrations at limestone quarry from artificial neural network optimized by randomized and grid search cross-validation, and comparative analyses with blast vibration predictor models

  • Salman Ihsan;Shahab Saqib;Hafiz Muhammad Awais Rashid;Fawad S. Niazi;Mohsin Usman Qureshi
    • Geomechanics and Engineering
    • /
    • v.35 no.2
    • /
    • pp.121-133
    • /
    • 2023
  • The demand for cement and limestone crushed materials has increased many folds due to the tremendous increase in construction activities in Pakistan during the past few decades. The number of cement production industries has increased correspondingly, and so the rock-blasting operations at the limestone quarry sites. However, the safety procedures warranted at these sites for the blast-induced ground vibrations (BIGV) have not been adequately developed and/or implemented. Proper prediction and monitoring of BIGV are necessary to ensure the safety of structures in the vicinity of these quarry sites. In this paper, an attempt has been made to predict BIGV using artificial neural network (ANN) at three selected limestone quarries of Pakistan. The ANN has been developed in Python using Keras with sequential model and dense layers. The hyper parameters and neurons in each of the activation layers has been optimized using randomized and grid search method. The input parameters for the model include distance, a maximum charge per delay (MCPD), depth of hole, burden, spacing, and number of blast holes, whereas, peak particle velocity (PPV) is taken as the only output parameter. A total of 110 blast vibrations datasets were recorded from three different limestone quarries. The dataset has been divided into 85% for neural network training, and 15% for testing of the network. A five-layer ANN is trained with Rectified Linear Unit (ReLU) activation function, Adam optimization algorithm with a learning rate of 0.001, and batch size of 32 with the topology of 6-32-32-256-1. The blast datasets were utilized to compare the performance of ANN, multivariate regression analysis (MVRA), and empirical predictors. The performance was evaluated using the coefficient of determination (R2), mean absolute error (MAE), mean squared error (MSE), mean absolute percentage error (MAPE), and root mean squared error (RMSE)for predicted and measured PPV. To determine the relative influence of each parameter on the PPV, sensitivity analyses were performed for all input parameters. The analyses reveal that ANN performs superior than MVRA and other empirical predictors, andthat83% PPV is affected by distance and MCPD while hole depth, number of blast holes, burden and spacing contribute for the remaining 17%. This research provides valuable insights into improving safety measures and ensuring the structural integrity of buildings near limestone quarry sites.

Energy and Ileal Digestible Amino Acid Concentrations for Growing Pigs and Performance of Weanling Pigs Fed Fermented or Conventional Soybean Meal

  • Wang, Y.;Lu, W.Q.;Li, D.F.;Liu, X.T.;Wang, H.L.;Niu, S.;Piao, X.S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.27 no.5
    • /
    • pp.706-716
    • /
    • 2014
  • A new strategy of co-inoculating Bacillus subtilis MA139 with Streptococcus thermophilus and Saccharomyces cerevisiae was used to produce fermented soybean meal (FSBM). Three experiments were conducted to determine the concentration of digestible energy (DE) and metabolizable energy (ME) (Exp. 1), apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of amino acids (AA) (Exp. 2), and feeding value (Exp. 3) of FSBM produced by this new strategy (NFSB) compared with soybean meal (SBM) and conventionally available FSBM (Suprotein). In Exp. 1, twenty-four barrows (initial body weight [BW] of $32.2{\pm}1.7kg$) were randomly allotted to 1 of 4 diets with 6 replicates per diet. A corn basal diet and 3 diets based on a mixture of corn and 1 of 3 soybean products listed above were formulated and the DE and ME contents were determined by the difference method. The results showed that there were no differences in DE and ME between SBM and either FSBM product (p>0.05). In Exp. 2, eight barrows (initial BW of $26.8{\pm}1.5kg$) were fitted with ileal T-cannulaes and used in a replicated $4{\times}4$ Latin square design. Three corn-starch-based diets were formulated using each of the 3 soybean products as the sole source of AA. A nitrogen-free diet was also formulated to measure endogenous losses of AA. The results showed that the SID of all AA except arginine and histidine was similar for NFSB and SBM (p>0.05), but Suprotein had greater (p<0.05) SID of most AA except lysine, aspartate, glycine and proline than NFSB. In Exp. 3, a total of 144 piglets (initial BW of $8.8{\pm}1.2$ kg) were blocked by weight and fed 1 of 4 diets including a control diet with 24% SBM as well as diets containing 6% and 12% NFSB or 12% Suprotein added at the expense of SBM. During d 15 to 28, replacing SBM with 6% NFSB significantly improved average daily gain (ADG) and average daily feed intake (ADFI) (p<0.05) for nursery piglets. During the overall experiment, ADG of piglets fed diets containing 6% NFSB was significantly greater (p<0.05) than that of piglets fed SBM. In conclusion, fermentation with the new strategy did not affect the energy content or the AID and the SID of AA in SBM. However, inclusion of 6% NFSB in diets fed to nursery piglets improved performance after weaning likely as a result of better nutritional status and reduced immunological challenge.

Feasibility and Efficacy of Concurrent Chemoradiotherapy in Elderly Patients with Esophageal Squamous Cell Carcinoma: a Respective Study of 116 Cases from a Single Institution

  • Li, Xue;Zhao, Lu-Jun;Liu, Ning-Bo;Zhang, Wen-Cheng;Pang, Qing-Song;Wang, Ping;Yuan, Zhi-Yong
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.4
    • /
    • pp.1463-1469
    • /
    • 2015
  • Background: To evaluate the safety and efficacy of combined chemoradiotherapy or radiotherapy alone in elderly patients with esophageal carcinoma to identify the best method of treatment. Materials and Methods: One hundred and sixteen patients with esophageal carcinoma aged 70 and older who received definitive radiotherapy or chemoradiotherapy entered the study. Overall survival (OS), disease-free survival (DFS) and treatment-related toxicities were assessed. Results: The median OS of the overall population was 17.9 months. For patients treated with cCRT, sCRT and radiotherapy alone, the median OS was 22.3 months, 18.0 months and 12.4 months respectively(P=0.044). Median OS for patients treated with radiotherapy dose ${\geq}60Gy$ and <60Gy was 20.2 months and 10.9 months respectively (p=0.017). By univariate analysis, Chemoradiotherapy (include cCRT and sCRT) and radiotherapy dose ${\geq}60Gy$ were found to achieve higher survival rates compared with radiotherapy alone and radiotherapy dose <60Gy (P=0.015, P=0.017). By multivariate analysis, chemoradiotherapy (HR=1.645, P=0.022) and radiotherapy dose ${\geq}60Gy$ (HR=1.642, P=0.025) were identified as independent prognostic factors of OS. Conclusions: Definitive concurrent chemoradiotherapy could be considered as a feasible and effective treatment in esophageal carcinoma patients aged 70 and older. Radiotherapy dose 60Gy is an effective treatment option compared with standard dose radiotherapy, while higher doses are not beneficial to improve survival.

Comparison of Efficacy and Toxicity of First Line Chemotherapy with or without Epirubicin for Patients with Advanced Stage Soft Tissue Sarcoma

  • Cao, Jie;Huang, Xin-En;Liu, Jin;Wu, Xue-Yan;Lu, Yan-Yan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.12
    • /
    • pp.7171-7177
    • /
    • 2013
  • Purpose: To compare the safety and efficacy of first-line chemotherapy regimen with or without doxorubicin in treating patients with advanced soft tissue sarcoma (STS). Patients and Methods: We retrospectively analyzed a cohort of 56 patients histologically confirmed with STS who were treated at Jiangsu Cancer Hospital and Research Institute from July 2011 to June 2012.The basic element of first line chemotherapy contained epirubicin in group B and lacked epirubicin in group A. Response was assessed using RECIST criteria. The Kaplan-Meier method was used to estimate progress free survival (PFS). Results: According to RECIST criteria, patients in group treated by chemotherapy without epirubicin, the objective response (OR) ratio was 6.5 % (CR0%+PR6.5%). Disease control rate (DCR=CR+PR+SD) was 25.8% with a median follow-up of 14.6 months, including 2 patients achieving a partial response (PR 6.5%) and a stable response (SD 19.4%) in 6. In group B with epirubicin based regimens, no patient had complete response, PR (28 %) was observed in 7 and SD (24 %) in 6. DCR was observed in 13 patients (52%). By Fisher's exact test, the DCR difference between the two groups was statistically significant (p=0.046). In group A, median PFS was 3.0 months (95%CI:2.1-3.8), compared with 4.0 months (95% CI:3.03-4.97) in group B (p=0.0397 by log-rank test). Epirubicin based chemotherapy and ECOG performance status 0-1 were identified as favorable factors for progression in our cohort of patients. Differences of nonhematologic and hematologic toxicities were not statistically significant between the two groups, and the addition of epirobicin was not associated with cardiac toxicity (p=0.446). Conclusion: Our study demonstrates that epirubicin-based chemotherapy is effective and well tolerated, and is superior to chemotherapy without epirubicin regarding efficacy. Therefore it is recommended that epirubicin-based chemotherapy should be considered as first line for patients with advanced STS.

Rapid Detection and Monitoring Therapeutic Efficacy of Mycobacterium tuberculosis Complex Using a Novel Real-Time Assay

  • Jiang, Li Juan;Wu, Wen Juan;Wu, Hai;Ryang, Son Sik;Zhou, Jian;Wu, Wei;Li, Tao;Guo, Jian;Wang, Hong Hai;Lu, Shui Hua;Li, Yao
    • Journal of Microbiology and Biotechnology
    • /
    • v.22 no.9
    • /
    • pp.1301-1306
    • /
    • 2012
  • We combined real-time RT-PCR and real-time PCR (R/P) assays using a hydrolysis probe to detect Mycobacterium tuberculosis complex (MTBC)-specific 16S rRNA and its rRNA gene (rDNA). The assay was applied to 28 non-respiratory and 207 respiratory specimens from 218 patients. Total nucleic acids (including RNA and DNA) were extracted from samples, and results were considered positive if the repeat RT-PCR threshold cycle was ${\leq}35$ and the ratio of real-time RT-PCR and real-time PCR load was ${\geq}1.51$. The results were compared with those from existing methods, including smear, culture, and real-time PCR. Following resolution of the discrepant results between R/P assay and culture, the overall sensitivity, specificity, positive predictive values (PPV), and negative predictive values (NPV) of all samples (including non-respiratory and respiratory specimens) were 98.2%, 97.2%, 91.7%, and 99.4%, respectively, for R/P assay, and 83.9%, 89.9%, 72.3%, and 94.7%, respectively, for real-time PCR. Furthermore, the R/P assay of four patient samples showed a higher ratio before treatment than after several days of treatment. We conclude that the R/P assay is a rapid and accurate method for direct detection of MTBC, which can distinguish viable and nonviable MTBC, and thus may guide patient therapy and public health decisions.

Analysis on Survival and Prognostic Factors for Cancer Patients with Malignancy-associated Hypercalcemia

  • Zhang, Su-Jie;Hu, Yi;Cao, Jing;Qian, Hai-Li;Jiao, Shun-Chang;Liu, Zhe-Feng;Tao, Hai-Tao;Han, Lu
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.11
    • /
    • pp.6715-6719
    • /
    • 2013
  • Objective: To explore the incidence, clinical characteristics, diagnosis and treatment strategies, prognosis of patients with malignancy-associated hypercalcemia (MAH). Methods: The data of 115 patients with MAH who were treated at the Medical Oncology Department of Chinese PLA General Hospital from Jan., 2001 to Dec., 2010 was retrospectively reviewed. Survival analysis was performed using the Kaplan-Meier method and the Cox proportional hazard model with statistic software SPSS 18.0. Results: The patients had blood calcium levels ranging from 2.77 to 4.87 mmol/L. Except for 9 cases who died or were discharged within 5 days after admission, all other patients recovered to normal blood calcium level after treatment with bisphosphonates or intravenous hydration and diuretics; their survival after occurrence of MAH was from 1 day to 4,051 days, and the median survival time was only 50 days. In the log-rank test, the male, renal metastasis, central nervous system symptoms and hypercalcemia occurring over 140 days after cancer diagnosis were predictors of poor survival (P=0.002, P=0.046, P=0.000, P=0.009). In the COX analysis, being male, central nervous system symptoms and hypercalcemia lasting over 140 days after cancer diagnosis were independent prognostic factors for survival time (RR=2.131, P=0.027; RR=3.054, P=0.002; RR=2.403, P=0.001). According to these factors, a score system was established to predict the patient prognosis and adjust the treatment. Conclusion: Cancer patients with MAH have an extremely poor median survival. Some independent factors indicate poor prognosis, including male gender, central nervous system symptoms and hypercalcemia lasting over 140 days after cancer diagnosis. The prognostic score can serve as a reference for MAH prognosis and treatment, worthy of further investigation.