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101.
Visual Inspection of Highway Bridges 总被引:1,自引:0,他引:1
Benjamin A. Graybeal Brent M. Phares Dennis D. Rolander Mark Moore Glenn Washer 《Journal of Nondestructive Evaluation》2002,21(3):67-83
The Federal Highway Administration recently conducted an investigation to assess the reliability of visual inspection of highway bridges as implemented by state departments of transportation. The study focused on routine and in-depth inspection, the two most prevalent forms of visual inspection of bridges. Because visual inspection is a highly subjective nondestructive evaluation technique, the results of these bridge inspections can be highly variable and are dependent on many factors. This study included the completion of 10 bridge inspection tasks by 49 practicing state bridge inspectors. With regard to routine inspections, this study showed that condition ratings are assigned with significant variability. Specifically, approximately 68% of condition ratings are within 1 rating point of the average. The results of the in-depth superstructure inspections indicated that these inspections are not likely to detect and identify the specific types of defects for which this inspection procedure is sometimes prescribed. Specifically, widespread defects such as those normally noted during a routine inspection are likely to be noted; however, local deficiencies, such as crack indications, are unlikely to be detected. The results of the deck delamination survey indicate that the accuracy of this type of inspection is relatively poor, with few inspection teams providing results that could be considered to accurately portray the condition of the deck. 相似文献
102.
Yamaoka M. Yanagisawa K. Shukuri S. Norisue K. Ishibashi K. 《Solid-State Circuits, IEEE Journal of》2002,37(5):599-604
A new memory redundancy technique using inverse-gate-electrode flash (ie-flash) memory cells has been developed. The ie-flash can be fabricated by the conventional logic CMOS process, so no additional processes are necessary in using it in system LSIs, and it can be programmed by logic testers. We enhanced the reliability of ie-flash by using some circuits, increasing reliability to endure practical use. This new redundancy technique was successfully implemented in the cache memories of a 32-b RISC microprocessor 相似文献
103.
Y Ohnishi S Tajima A Ishibashi T Inazumi T Sasaki H Sakamoto 《Canadian Metallurgical Quarterly》1998,139(1):141-144
Fourier transform infrared and Raman (FT-IR and FT-Raman) microspectroscopy were used to study materials found in human tissue. Individual cases involving cholesterol, calcium stearate, and a polystyrenesulfonate ion exchange resin demonstrate the utility of the spectroscopic data. Characteristic spectral bands for these materials were compared with those of authentic chemical species to confirm their identities. The role of vibrational spectroscopy in pathologic diagnoses is discussed. 相似文献
104.
We previously described a high incidence of digit/limb anomalies in the offspring of A/J mice subjected to surgery on day 12.5 postconception (p.c.), but not in the offspring of untreated control mice. To investigate the cause of these defects, we compared the offspring of mice in experimental groups involving adrenalectomy, sham adrenalectomy, blood sampling, and anesthesia with the offspring of control mice. All treatments significantly reduced fetal weight and increased resorptions as compared with the controls. The highest incidence of digit anomalies occurred in the offspring of dams from which blood samples had been drawn on days 12.5, 14.5, and 15.5 p.c. The incidence of isolated cleft palate was also increased in the offspring of mice that had been subjected to blood sampling. We conclude that digit anomalies in the offspring of A/J mice result from fetal vascular disruptive phenomena subsequent to maternal blood loss induced hypovolemia and hypoperfusion to the uterus and placenta as has been suggested for uterine vascular clamping, misoprostol, chorionic villus sampling, and cocaine teratogenesis. The etiology for cleft lip in these mice may involve mechanisms unrelated to uterine/placental hypoperfusion. 相似文献
105.
106.
Y Sakai H Minagawa T Ishibashi H Inomata R Mori 《Canadian Metallurgical Quarterly》1994,208(3):157-160
The antibody responses of 65 volunteers receiving an i.d. regimen (0.1 ml given at two sites on days 0, 3, 7 and 0.1 ml given at one site on days 30 and 90) were compared with the control group of 35 volunteers receiving the standard i.m. regimen. By day 14, seroconversion was observed in all vaccinees in both groups. Geometric Mean Titers remained higher than 0.5 IU/ml throughout the study period. At the end of the observation period on day 365, antibodies persisted in all subjects. The multisite i.d. PCEC regimen has been proved as immunogenic as the standard i.m. regimen. Both regimens were well tolerated. Thus, it would be the effective and cheapest available rabies post-exposure treatment using tissue culture vaccine. 相似文献
107.
Thiourea has been extensively used as a grain refiner in industrial copper electrorefining processes. The influence of thiourea
on deposit structure and morphology has received considerable study; however, the effect of thiourea and its degradation chemistry
on the passivation behavior of commercial copper anodes is still not fully understood. This study was conducted to provide
useful information regarding the electrochemical response of a commercial copper anode in the absence and presence of thiourea.
Chronopotentiometry measurements were performed in synthetic electrolytes containing different thiourea concentrations and
in industrial electrolytes obtained directly from a commercial tank house. Passivation time (t
p
) and periodic passivation phenomena were found to be closely associated with thiourea concentration and degradation. 相似文献
108.
M Niki H Isozaki M Toyoda T Ishibashi K Fujii E Nomura H Mabuchi M Nakamura K Nishiguchi N Tanigawa 《Canadian Metallurgical Quarterly》1998,45(24):2458-2463
BACKGROUND/AIMS: Hepatocyte growth factor (HGF) is a stromally derived protein growth factor that modulates epithelial cell proliferation and motility. HGF may therefore be involved in tumor progression. METHODOLOGY: We measured the immunoreactive (ir)-HGF concentration in the sera of 56 patients with human gastric carcinoma, using an enzyme-linked immunosorbent assay and evaluated its association with clinical and histopathologic factors. Clinical stages were classified in accordance with The General Rules for TNM Classification (International Union Against Cancer). RESULTS: The serum hHGF concentrations from patients with gastric carcinoma significantly increased with increasing pathologic tumor grades. Also, there were significantly higher concentrations in patients with nodal metastasis compared to patients without metastasis. The serum hHGF concentrations in patients with liver metastasis were significantly higher than in patients without liver metastasis. CONCLUSIONS: These data show that the serum hHGF concentration is elevated in gastric carcinoma patients with liver and nodal metastasis. In multivariate analysis, the serum hHGF concentration was found to be the most important independent factor in predicting overall survival. Thus, the current results suggest that HGF may be important in the progression and metastasis of gastric carcinoma. 相似文献
109.
110.