Conventional displacement sensors have limitations in practical applications. This paper develops a vision sensor system for remote measurement of structural displacements. An advanced template ...matching algorithm, referred to as the upsampled cross correlation, is adopted and further developed into a software package for real-time displacement extraction from video images. By simply adjusting the upsampling factor, better subpixel resolution can be easily achieved to improve the measurement accuracy. The performance of the vision sensor is first evaluated through a laboratory shaking table test of a frame structure, in which the displacements at all the floors are measured by using one camera to track either high-contrast artificial targets or low-contrast natural targets on the structural surface such as bolts and nuts. Satisfactory agreements are observed between the displacements measured by the single camera and those measured by high-performance laser displacement sensors. Then field tests are carried out on a railway bridge and a pedestrian bridge, through which the accuracy of the vision sensor in both time and frequency domains is further confirmed in realistic field environments. Significant advantages of the noncontact vision sensor include its low cost, ease of operation, and flexibility to extract structural displacement at any point from a single measurement.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Ubiquitous smartphones have created a significant opportunity to form a low-cost wireless Citizen Sensor network and produce big data for monitoring structural integrity and safety under operational ...and extreme loads. Such data are particularly useful for rapid assessment of structural damage in a large urban setting after a major event such as an earthquake. This study explores the utilization of smartphone accelerometers for measuring structural vibration, from which structural health and post-event damage can be diagnosed. Widely available smartphones are tested under sinusoidal wave excitations with frequencies in the range relevant to civil engineering structures. Large-scale seismic shaking table tests, observing input ground motion and response of a structural model, are carried out to evaluate the accuracy of smartphone accelerometers under operational, white-noise and earthquake excitations of different intensity. Finally, the smartphone accelerometers are tested on a dynamically loaded bridge. The extensive experiments show satisfactory agreements between the reference and smartphone sensor measurements in both time and frequency domains, demonstrating the capability of the smartphone sensors to measure structural responses ranging from low-amplitude ambient vibration to high-amplitude seismic response. Encouraged by the results of this study, the authors are developing a citizen-engaging and data-analytics crowdsourcing platform towards a smartphone-based Citizen Sensor network for structural health monitoring and post-event damage assessment applications.
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Empty fruit bunch (EFB) biomass, one of the most abundant biomass residues in Southeast Asia, was gasified using H2O (steam) or H2O+O2 as a gasification agent in an entrained-flow gasifier at 900°C. ...During gasification with H2O alone, the EFB gasification rate was >95% (C-equivalent), and hydrogen-rich gas with a composition suitable for liquid fuel synthesis (H2/CO≈1.8–3.9, depending on the H2O/C ratio) was obtained. The gasification rate improved (to >99%) when O2 was added to H2O; however, under these conditions, the gas composition was less suitable for liquid fuel synthesis (the amount of CO2 increased, the amounts of CO and H2 decreased, and the H2/CO ratio decreased). Nevertheless, the H2/CO ratio was sufficient (∼2) for liquid fuel synthesis. We also performed thermogravimetric (TG) analysis of EFB using a thermobalance specially designed for analysis of feedstock in the presence of O2, H2O, or both. TG analysis suggested that EFB decomposed easily, especially in the presence of H2O and/or O2. The results obtained from TG analysis and gasification agreed well. In gasification, the tar yield was low (<0.1wt.%), and the tar was composed mainly of six compounds, including naphthalene; these results suggest that the primary tar decomposed and that gasification proceeded quite well. The yield of solid residues was low, and the soft, yellow residues, which partially adhered to the gasifier wall, were composed mainly of ash. These solid residues would require treatment in a large-scale gasifier.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Japanese cedar (Cryptomeria japonica) wood and bark were gasified using an entrained-flow-type gasification reactor at 900 °C in the presence of H2O or H2O + O2. With H2O alone, the cedar wood was ...gasified well: carbon conversion into gas CC(g) = 94.3%; however, cedar bark was not gasified so well: CC(g) = 73.4%, and relatively large amounts of solid residues were produced: carbon conversion into solid residues CC(sr) = 14.0%. Gas produced from both cedar wood and cedar bark were suitable compositions for catalytic liquid fuel synthesis: H2/CO ≅ 2–3. Tar yields were low: that from the cedar wood was <0.1 wt %, and that from the cedar bark was 0.3 wt %. The tar from the cedar bark contained much more various kinds of compounds. With H2O + O2, CC(g) was improved (cedar wood, 96.5%; cedar bark, 87.5%) and CC(sr) of the cedar bark decreased (2.6%). A high lignin content in the cedar bark was one of main differences from the cedar wood and was a possible reason for its low CC(g). To examine the effect of the lignin on gasification, organosolv-lignin (o-lignin) and delignified cedar bark were also gasified. The CC(g) of the o-lignin was low, 59.9%, with H2O alone and increased to 81.4% with H2O + O2, whereas that of the delignified cedar bark was high, 95.4%, with H2O alone and increased to 103.6% with H2O + O2. The Japanese cedar wood, cedar bark, delignified cedar bark, and o-lignin were thermogravimetrically analyzed in He with H2O or H2O + O2. Their decompositions proceeded more in He with H2O + O2 than with H2O. We ordered them according to easiness of decomposition: delignified bark > wood > bark > o-lignin, in all of these atmospheric conditions. Effects of feedstock and atmosphere on the gasification and thermogravimetric analyses had the same tendencies. We, therefore, concluded that the lower CC(g) of the cedar bark than the cedar wood was attributable to difficulties of gasifying the lignin components.
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: We aimed to determine the trends over time and current status of early
-uninfected gastric cancer (HpUIGC) treatment in a region with an aging population.
: This retrospective, multi-center ...observational study was conducted at seven major general hospitals in Kagoshima Prefecture. From January 2009 to July 2022, 2091 patients who received endoscopic resection (ER) for early gastric cancer (EGC) were retrospectively enrolled, of which 35 were identified as early HpUIGC cases.
: The number of ERs for EGC demonstrated a significant increasing trend from 2010 to 2021 (
= 0.01 for trend). Furthermore, the 12-year period from 2010 to 2021 was divided into an early and late phase every 6 years. In the early phase, there were 5 cases (0.7%) of early HpUIGC, while in the late phase, there were 25 cases (2.1%), indicating a significant increase in the proportion of ERs for early HpUIGC cases in the late phase (
= 0.02).
: The proportion of ERs for early HpUIGC, which are more common in relatively young patients, may be increasing as a proportion of all ERs for GC, even in areas of Japan with an aging population.
A 64-year-old man presented to our hospital with abdominal pain and 4–5 episodes of watery diarrhea per day for 2 months. Abdominal ultrasound examination revealed a mass in the peritoneal cavity, ...and computed tomography showed a 13.4 cm mass in the mesentery and a 3 cm mass in the mesocolon. The patient underwent laparoscopic partial resection for diagnosis. Microscopically, abundant fibrosis and numerous immunoglobulin (Ig) G4-positive plasma cells were observed. The serum level of IgG4 was 665 mg/dl postoperatively. These findings suggested that the lesion was consistent with IgG4-related sclerosing mesenteritis. Oral steroids resulted in rapid disappearance of symptoms and a decrease in masses. Recently, sclerosing mesenteritis are reported as IgG4-related disease or mimicking IgG4-related disease but multiple lesions rarely occur in the same organ. We report a case of IgG4-related sclerosing mesenteritis with multiple lesions without involvement of other organs, such as the pancreas and salivary glands.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Continuous inspection of the concrete structures is important for extending the operating life span of nuclear power plants. Restricted physical accessibility to the nuclear plant structures, due to ...concerns of radiation, presents a unique challenge to the conventional visual inspection and contact-type nondestructive evaluation (NDE) technologies. Digital image correlation (DIC) is an optical NDE method that can measure the structural parameters such as displacement and strain. However, it is highly challenging to accurately detect micro displacement on the concrete surface because of weathering and change in illumination conditions. Usually, an artificial speckle pattern with good contrast to the object surface is needed for calibration and tracking, but it is difficult to apply in the field. In order to be able to detect micro surface strain for crack prediction in outdoor environment, a DIC-based NDE technology is developed to significantly improve the measurement accuracy by incorporating the orientation code matching (OCM) technique, a robust and accurate template matching algorithm. Concrete specimens were built and tested under four-point bending. Using the remotely measured images, the OCM incorporated DIC method successfully predicted concrete cracks before they emerged on the surface. The experiments also demonstrated the robustness of the method against the optical noise including weathering and change in illumination conditions.
AbstractDisplacements of railroad bridges under trainloads need to be closely monitored, but conventional displacement sensors have limitations for use in the field. This paper presents a new ...vision-based sensor system developed for remote measurement of structural dynamic displacements without requiring a specially installed target-marker panel. By implementing a robust object-search algorithm, the displacement can be accurately measured by tracking existing bridge surface features from a remote distance. The accuracy of measured dynamic displacements was first evaluated using a shaking table test. Then field tests were carried out on two railroad bridges subjected to freight trainloads traveling at various speeds. Measurements were taken remotely during the daytime and also at night from different distances with and without a target panel. Through comparison with a conventional contact-type displacement sensor, the high accuracy of the proposed nontarget remote-sensor system was demonstrated in the realistic field environments. From the measured displacement time histories, frequency-domain characteristics associated with the train–bridge systems were further analyzed, confirming the capability of the vision system in measuring high-frequency components. By targeting existing features on a structure without requiring a target panel installed on a fixed location of the structure, the vision sensor system developed in this study provides the flexibility to easily change displacement measurement locations, in addition to other advantages, such as easy setup and no need to access the structure.
Stereochemistry of Pladienolide B Asai, Naoki; Kotake, Yoshihiko; Niijima, Jun ...
Journal of antibiotics,
06/2007, Volume:
60, Issue:
6
Journal Article
Peer reviewed
Open access
Pladienolide B is a 12-membered macrolide isolated from Streptomyces platensis Mer-11107. It showed potent in vitro and in vivo antitumor activities and is a potential lead for novel antitumor ...agents. The absolute configurations at ten chiral centers were determined on the basis of spectral data of pladienolide B and its chemical transformation products.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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