The feasibility study for reducing ship resistance was carried out. A thin plate was installed in front of bow to guide the air which was induced to the bottom just following to the hull surface when ship is running fast. To confirm the reduction of surface friction, model test in the high speed CWC and numerical simulation were implemented. The results show that the induced air to the bottom is increasing according to the increasing of air velocity and it plays an important role to reduce the frictional resistance.
Microbial distribution as well as content of salt and preservatives in side dishes was investigated by analyzing cell count of viable cells, coliform bacteria and food poisoning bacteria of sliced squid bokum and anchovy bokum, purchased at 17 dift'erent department stores and 2 different traditional markets in Seoul, which are most preferred by many consumers to any other side dishes available in the market. 6.2 × 10³-1.2 × 10^5 cells/g of viable cells was detected in 19 different samples of the sliced squid bokum, among which samples collected at the traditional markets counted the highest number of viable cells. 16 samples of the sliced squid bokum and 14 samples of the anchovy bokum contained 10³-10^8 cells/g of coliform group. However food poisoning bacteria were not detected in all the samples tested. Salt content was 2.42-4.89 %w/w and 2.28-6.46 %w/w for the sliced squid bokum and the anchovy bokum respectively. Analysis of preservatives by HPLC such as sorbic acid, benzoic acid, dehydroacetic acid and another 6 kinds of esters resulted that 1.0× 73.8 mg/100 g of sorbic acid was detected in the 19 samples of the sliced squid bokum, while only 6 samples of the 15 anchovy bokum samples contained sorbic acid.
Recently, the slope failure, which is frequently happened in Ice-melting season, attracts attention in South Korea. The increasing trend in frequency of freezing-thawing process has regarded as major reason of slope failure. However, the time and check level are not reflected at the safety assessments and inspection guidelines. Therefore, the characteristics of slope in ice-melting season should be considered to improve the slope stability in ice-melting season. The purpose of this study is to evaluate the influence of the potential risk factors on the slope stability for development of the slope checklist reflecting the timing and check level based on the slope inspection checklist which is provided by the recent research.
As the road sink phenomenon occurred continuously at the center of seoul in 2014. The road sink phenomenon was emerged as a social big issue in korea. So far, government, municipalities and related experts have been making a lot of efforts to prevent road sink accident, but it is still happening all over the country. Therefore, In this study aims to present the restoration action procedures and checklist items that can be used by government officials in order to recover quickly in the event of a road sink.
Recently, there have been many studies to classify the image-based damage of bridge using the deep learning and to evaluate the condition. These attempts are one of the ways to overcome limitations of visual inspection through inspectors, and it is also aimed to reduce the cost of necessary maintenance budget by enabling accurate and rapid damage assessment of rapidly growing old facilities and difficult parts of visual inspection. However, it is possible to classify and quantitatively express simple damage (one damage classification such as cracks) with image information (big data) of bridges, but classification and quantification of complex damage can be done by using one deep learning is a limit. Therefore, this study presents considerations and a method to be used for damage detection on the image basis using deep learning.
In this study, the bridge management system framework for the application of UAV collection data was proposed. The framework of UAV Bridge Management System(UBMS) is designed based on algorithm of Bridge Management System(BMS), administered by MOLIT. The UAV Bridge Management System will help facility managers to conduct safety diagnosis by providing rapid procedure.
In this study, to improve prevention system against disasters for marine bridges, the related references of marine bridges were analysed. As a result, the guideline of prevention facilities against disasters for marine bridges was proposed. This study will be referred for establishing related standards.
In this study, to improve the marine bridge disaster prevention system, the trend of disaster accidents due to the extension of maritime bridges was analyzed and the status of domestic and foreign disaster prevention facilities was examined. As a result of the review, it was aimed at presenting the disaster prevention facility grade and installation items considering the size of the bridge and traffic volume.
This study was performed to evaluate the cable tension of cable-stayed bridge by using vibration method and Lift-Off Test. As a result, cable tension by the vibration method and Lift-Off Test is most similar.
This study on the maintenance of axial force of the cable band bolts in suspension bridge. The axial force on the cable band is reduced as suspension bridge of increases service period. In is a summary of the field measurement results and review of cause.
In this study, measurement temperature in the bridges was compared with temperature proposed by Korean design code. In addition, the structural analysis was performed in order to comparing the stress by measured thermal load and the stress by design thermal load. As a result, the stress that applied measurement temperature was evaluated larger than the stress that applied temperature proposed by Korean design code.
In this study, the structural assessment on the effect of differential deformation of HDRB was performed for double deck warren truss bridge. The results show that the differential deformation of HDRB sharply decreases the safety rate of the superstructure of the bridge.
This paper carried out a study on design for the deviation block of PSC box girder bridges with external tendons. As a result, the actual load distribution on deviation block must be considered for design because of a discordance with the design concept.
In this study, periodical configuration survey is carried out on the subject of the suspension bridge in service. Its reliability and structural modeling validity are performed by comparison and analysis of interpretation value through the structural analysis.
This paper developed analysis model with measured data and geometric nonlinearity for more precise evaluation of structure behavior of suspension bridge. This analysis model helps to make plan and evaluate of structure behavior for accidents such as traffic, typhoon and earthquake. Also, this helps to make maintenance and management plan for structure.
In this study, analyze the proper repair works and after repair works before it, such as via the structural analysis and investigation of various site of damaged of suspension bridge due to the collision of the vehicle is an accident artificial, make sure those good analysis result has been.