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Identification of moving train loads on railway bridge based on strain monitoring

  • Wang, Hao;Zhu, Qingxin;Li, Jian;Mao, Jianxiao;Hu, Suoting;Zhao, Xinxin
    • Smart Structures and Systems
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    • 제23권3호
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    • pp.263-278
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    • 2019
  • Moving train load parameters, including train speed, axle spacing, gross train weight and axle weights, are identified based on strain-monitoring data. In this paper, according to influence line theory, the classic moving force identification method is enhanced to handle time-varying velocity of the train. First, the moments that the axles move through a set of fixed points are identified from a series of pulses extracted from the second derivative of the structural strain response. Subsequently, the train speed and axle spacing are identified. In addition, based on the fact that the integral area of the structural strain response is a constant under a unit force at a unit speed, the gross train weight can be obtained from the integral area of the measured strain response. Meanwhile, the corrected second derivative peak values, in which the effect of time-varying velocity is eliminated, are selected to distribute the gross train weight. Hence the axle weights could be identified. Afterwards, numerical simulations are employed to verify the proposed method and investigate the effect of the sampling frequency on the identification accuracy. Eventually, the method is verified using the real-time strain data of a continuous steel truss railway bridge. Results show that train speed, axle spacing and gross train weight can be accurately identified in the time domain. However, only the approximate values of the axle weights could be obtained with the updated method. The identified results can provide reliable reference for determining fatigue deterioration and predicting the remaining service life of railway bridges.

Nonlinear boundary parameter identification of bridges based on temperature-induced strains

  • Wang, Zuo-Cai;Zha, Guo-Peng;Ren, Wei-Xin;Hu, Ke;Yang, Hao
    • Structural Engineering and Mechanics
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    • 제68권5호
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    • pp.563-573
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    • 2018
  • Temperature-induced responses, such as strains and displacements, are related to the boundary conditions. Therefore, it is required to determine the boundary conditions to establish a reliable bridge model for temperature-induced responses analysis. Particularly, bridge bearings usually present nonlinear behavior with an increase in load, and the nonlinear boundary conditions cause significant effect on temperature-induced responses. In this paper, the bridge nonlinear boundary conditions were simulated as bilinear translational or rotational springs, and the boundary parameters of the bilinear springs were identified based on the measured temperature-induced responses. First of all, the temperature-induced responses of a simply support beam with nonlinear translational and rotational springs subjected to various temperature loads were analyzed. The simulated temperature-induced strains and displacements were assumed as measured data. To identify the nonlinear translational and rotational boundary parameters of the bridge, the objective function based on the temperature-induced responses is then created, and the nonlinear boundary parameters were further identified by using the nonlinear least squares optimization algorithm. Then, a beam structure with nonlinear translational and rotational springs was simulated as a numerical example, and the nonlinear boundary parameters were identified based on the proposed method. The numerical results show that the proposed method can effectively identify the parameters of the nonlinear boundary conditions. Finally, the boundary parameters of a real arch bridge were identified based on the measured strain data and the proposed method. Since the bearings of the real bridge do not perform nonlinear behavior, only the linear boundary parameters of the bridge model were identified. Based on the bridge model and the identified boundary conditions, the temperature-induced strains were recalculated to compare with the measured strain data. The recalculated temperature-induced strains are in a good agreement with the real measured data.

Comprehensive investigation of the expression profiles of common long noncoding RNAs during microglial activation

  • Janghyun Kim;Bora Lee;Young Kim;Byeong C. Kim;Joon-Tae Kim;Hyong-Ho Cho
    • Genomics & Informatics
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    • 제21권1호
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    • pp.2.1-2.14
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    • 2023
  • Microglia, similar to peripheral macrophages, are the primary immune cells of the central nervous system (CNS). Microglia exist in the resting state in the healthy CNS, but can be activated and polarized into either M1 or M2 subtypes for immune defense and the maintenance of CNS homeostasis by multiple stimuli. Several long noncoding RNAs (lncRNAs) mediate human inflammatory diseases and neuropathologies by regulating their target genes. However, the function of common lncRNAs that contribute to microglial activation remains unclear. Thus, we used bioinformatic approaches to identify common lncRNAs involved in microglial activation in vitro. Our study identified several lncRNAs as common regulators of microglial activation. We identified 283 common mRNAs and 53 common lncRNAs during mouse M1 microglial activation processes, whereas 26 common mRNAs and five common lncRNAs were identified during mouse M2 microglial activation processes. A total of 648 common mRNAs and 274 common lncRNAs were identified during the activation of human M1 microglia. In addition, we identified 1,920 common co-expressed pairs in mouse M1 activation processes and 25 common co-expressed pairs in mouse M2 activation processes. Our study provides a comprehensive understanding of common lncRNA expression profiles in microglial activation processes in vitro. The list of common lncRNAs identified in this study provides novel evidence and clues regarding the molecular mechanisms underlying microglial activation.

경추 전방 유합 환자의 장기 수술 결과에 영향을 주는 방사선학적 요인 분석 (Analysis of Radiologic Factors Affecting Longterm Surgical Results of Anterior Cervical Fusion Patients)

  • 최일승;서대희;박성춘;채의병;최선욱;송관영;강동수
    • Journal of Korean Neurosurgical Society
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    • 제30권2호
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    • pp.194-200
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    • 2001
  • Object : Anterior cervical discectomy and fusion is accepted as appropriate surgical intervention for disease processes of the ventral cervical spine. In some cases, however, improvement of symptom following operation develop myelopathy or rhizopathy at longterm follow-up. We studied to clarify the correlation between clinical results and plain radiologic findings at long term follow-up. Methods : A total of 86 patients who underwent anterior cervical discectomy and fusion were grouped into deteriorated and good recovery group. These two groups were compared in lateral functional roentgenograms on the cervical kyphosis and disc height at fused level, sagittal plane rotation and dynamic sagittal canal diameter at adjacent level. Results : The presence of cervical kyphosis and disc height at fused level do not correlate with long term followup results. Sagittal plane rotation of more than 20 degrees were identified in 36% of the cases in deteriorated group, whereas the same findings were identified in 15% of the cases in good group. Sagittal diameter of less than 12mm were identified in 48% of the cases in deteriorated group, whereas the same finding were identified in 8% of the cases in good group. Preoperatively, sagittal plane rotation of more than 20 degrees at adjacent level were identified in 28% of the cases in deteriorated group, whereas the same findings were identified in 13% of the cases in good group. Preoperatively sagittal diameter of less than 12mm at adjacent level were identified in 40% of the cases in deteriorated group, whereas the same finding were identified in 7% of the cases in good group. Conclusion : Large sagittal plane rotation and small dynamic sagittal diameter at adjacent level were factors that might be associated with later clinical deterioration after cervical anterior fusion.

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Effects of Identified Outliers for Parametric Estimators in a Pareto

  • Jungsoo Woo;Changsoo Lee
    • Communications for Statistical Applications and Methods
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    • 제3권1호
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    • pp.195-206
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    • 1996
  • Several parametric estimators of the scale parameter and reliability in an assumed Pareto distribution with the presence of identified outliers are proposed, and their efficiencies are compared numerically each other.

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TRICHOTHECENES AS ENVIRONMENTAL TOXICANTS

  • Ueno, Yoshio
    • Toxicological Research
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    • 제1권1호
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    • pp.1-15
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    • 1985
  • The trichothecenes are a chemically related sesquiterpenoid fungal metabolites of Fusarium, Trichoderma, Stachybotrys and others, and at moment more than 70 kinds of derivatives are identified. Historically, they are identified as antifungal and phytotoxic compounds, but after the finding of T-2 toxin from Fusarium tricinctum, several trichothecenes are now considered to be natural toxicants in foodstuffs and feeds.

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홍조 Rhodochorton 속의 분류학적 연구 (Some Members of Rhodochorton (Rhodophyta) in Korea)

  • 이인규
    • Journal of Plant Biology
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    • 제17권1호
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    • pp.36-52
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    • 1974
  • Nine members of Rhodochorton appearing in coastal waters of Korea were investigated diagnostically. Among them, Rh. densum, Rh. magnificum, Rh. robustum and Rh. codicola were identified previously, while Rh. terminale, Rh. sancti-thomae, Rh. daviesii, Rh. hyalosiphoniae, and Rh. rhizoideum were identified and described for the first time in this country.

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Identification of Hepatitis B (HBV) and C (HCV) Virus Infection among Doctors and Nurses in Tertiary Hospitals in Mongolia

  • Batbold, D.;Baigalmaa, Dovdon;Ganbaatar, B.;Chimedsuren, O.
    • Perspectives in Nursing Science
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    • 제7권1호
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    • pp.50-54
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    • 2010
  • The studies of M. Colombo (1989) and W. Lange (1992) showed that 30~40% of people became chronic after suffering from hepatitis B virus (HBV) and C virus (HCV) infection, and about 50% of the chronic cases transformed into primary liver cancer. There have been few studies done in Mongolia on hepatitis infection among health professionals, particularly in nurses. In a study done by Chimedsuren (8), the study showed that 19.4% of people with identified surface hepatitis B antigen (HBsAg) and antibodies to hepatitis C virus and 8% of people with the identified nucleotide of RNA for the hepatitis C virus (polymerase chain reaction) had an acute form of hepatitis C. Studies on the hepatitis virus genome damaging effect on liver cells showed that genotype 8 (A, B, C, D, E, F, G, TTV) had the most damaging effect on liver cells (Hahn and Faeka, 2007). Several studies have shown a relationship between hepatitis B virus infection and a lack of compliance regarding safety regulations and rules by medical personnel. Results of a study from the Maternal and Child Health Research Center showed that tests done to detect hepatitis B virus antigen and antibodies to C virus did not reveal anything. Both antigen and antibodies in 69% cases did not show, and separately, B virus and antibodies to hepatitis C virus were identified in 13% and 9%, respectively. Results of the tests taken from health personnel in Shastin Central Hospital showed that in 76% of the cases, the B virus antigen with C virus antibodies was not identified. In 8% of the cases, the B virus antigen was present on its own. The combination of B the virus antigen and C virus antibodies were present in 8% of nurses and doctors, respectively. 82% of the cases had negative results for the detection of a combination of B virus antigen and C virus antibodies taken from health personnel from the State Central Clinical Hospital whereas the B virus antigen and C virus antibodies by themselves were present in 7% and 14% of the cases, respectively. Combined cases of the B virus antigen and C virus antibodies were identified in 4% of the personnel. Results of the tests taken from the health personnel in the Hospital of the Ministry of Justice and Internal Affairs showed that in 79% of the cases, the B virus antigen with C virus antibodies were not identified. Separately, the B virus and antibodies to hepatitis C virus were identified in 8% and 13% of the cases, respectively.

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Volatile Components in the Soy Sauce Manufactured by Bacillus Species and Fused Yeast

  • Kim, Haeng-Ja;Lee, Eun-Ju;Shin, Ok-Sun;Ji, Won-Dae;Choi, Myeong-Rak;Kim, Jong-Kyu
    • Journal of Microbiology and Biotechnology
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    • 제6권3호
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    • pp.194-201
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    • 1996
  • To develop a method appropriate for mass production in a factory, we manufactured soy sauce with Bacillus species SSA3-2M1 and fused ST723-F31 at $30^{\circ}C$ with aeration of 1/3 vvm for 40 days. The flavor components extracted from the manufactured soy sauce were fractionated to neutral, acidic, basic and phenolic fraction and identified by GC-mass. Among the 60 kinds of identified flavor components, 16 and 23 components were detected in traditional Korean soy sauce and soybean paste, respectively. There were three peak regions that smelled like soy sauce with the GC sniffing test of flavor components and 2, 6-dimethyl pyrazine, benzaldehyde, 2-methoxy phenol, phenol and benzeneethanol which were identified as character impact compounds of traditional Korean soy sauce and soybean paste were identified in the region that smelled like soy sauce. It is therefore considered possible to achieve mass production of soy sauce with standard quality by Bacillus species SSA3-2M1 and fused ST723-F31 in the factory.

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GALAXY FORMATION IN THE HUBBLE DEEP FIELD

  • PARK CHANGBOM;KIM JU HAN
    • 천문학회지
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    • 제30권1호
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    • pp.83-94
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    • 1997
  • We have identified the candidates for the primordial galaxies in the process of formation in the Hubble Deep Field (hereafter HDF). In order to select these objects we have removed objects brighter than 29-th magnitude in the HDF images and smoothed the maps with the Gaussian filters with the FWHM of 0.8' and 4' to obtain the difference maps. This has enabled us to find. very faint diffuse structures close to the sky level. Peaks are identified in the difference map for each of three HDF chips with three filters (F450W, F606W, and F814W). They have the apparent AB magnitudes typically between 29 and 31. The objects identified in different wavelengths filters have a strong cross-correlations. The correlation lengths are about 0.8'. This means that an object found in one filter can be also found as a peak within 0.8' separation in another filter, thus telling the reality of the identified objects. This angular scale is also the size of the primordial galaxies which have strong color fluctuations on their surfaces. Their large-scale distribution quite resembles that of nearby galaxies, supporting the idea that these objects are ancestors of the present bright galaxies forming at statistically high density regions. Inspections on individual objects show that these primordial galaxy candidates have tiny multiple glares embedded in diffuse backgrounds. Their radial light distributions are quite different from that of nearby bright galaxies. We may be now looking at the epoch of galaxy formation.

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