• Title/Summary/Keyword: damage monitoring

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Basic study of residual marine fuels quality (선박용 잔사유의 품질에 대한 기초연구)

  • Park, Hee-Woo;Chun, Kang-Woo;Kim, Jin-Hee
    • Journal of Advanced Marine Engineering and Technology
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    • v.40 no.4
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    • pp.362-368
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    • 2016
  • In the recent International Maritime Organization's (IMOs) Maritime Safety Committee's 93rd session, the International Chamber of Shipping and International Parcel Tankers Association addressed marine fuel oil quality problems: increasing diluents in marine fuel oil, ignition in engine rooms due to the low flash point of fuel oil, and marine fuel oils that can damage marine engines. To deal with these marine fuel oil quality problems, the International Maritime Organization secretariat appointed the worlds marine fuel oil monitoring institute and constituted a correspondence group to determine the fuel oil quality required by MARPOL Annex VI regulation 14.8 (sulfur content less than 0.5%). In this study, basic research that can help with responding to marine fuel quality issues and the IMO's work is conducted. In order to perform this basic research, the off-spec ratio related to the fuel oil quality standard (ISO 8217:2012), density distribution tendency, gross specific energy, and correlation between components in the fuel oil are analyzed through actual marine fuel oil (residual marine fuel) data from the Port of Singapore.

Cellular Immune Responses of the Manila Clam, Ruditapes philippinarum, Exposed to Cadmium Chloride (카드뮴에 노출된 바지락 (Ruditapes philippinarum) 의 세포성 면역 반응)

  • Park, Kyung-Il;Choi, Min-Soon;Park, Sung-Woo;Park, Kwan-Ha;Choi, Sang-Hoon;Yoon, Jong-Man
    • The Korean Journal of Malacology
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    • v.25 no.2
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    • pp.135-143
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    • 2009
  • The Manila clam, Ruditapes philippinarum, has been considered as a sentinel species due to dominant distribution along the coast of Korea and well developed regulatory system. In order to develop and understand immune responses of the Manila clams, clams were exposed to $50\;{\mu}g/L$ of cadmium chloride (Cd) for 8 days and monitored the cellular immune parameters of the hemocytes including blast cell composition, DNA damage, necrosis, apoptosis and hemocyte mortality using a flow cytometer. The results showed that all immune parameters analyzed in the present study increased remarkably compared to the controls and the increases were statistically significant. Apoptosis rate was higher than necrosis rate in the clams exposed to Cd suggesting that apoptosis was preferably induced by the concentration of Cd used in the present study. Our study indicates that the measurement of cellular immune responses of the Manila clam using flow cytometer will be a useful technique for assessment of heavy metal contamination in marine environment.

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Seismic safety assessment of eynel highway steel bridge using ambient vibration measurements

  • Altunisik, Ahmet Can;Bayraktar, Alemdar;Ozdemir, Hasan
    • Smart Structures and Systems
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    • v.10 no.2
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    • pp.131-154
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    • 2012
  • In this paper, it is aimed to determine the seismic behaviour of highway bridges by nondestructive testing using ambient vibration measurements. Eynel Highway Bridge which has arch type structural system with a total length of 216 m and located in the Ayvaclk county of Samsun, Turkey is selected as an application. The bridge connects the villages which are separated with Suat U$\breve{g}$urlu Dam Lake. A three dimensional finite element model is first established for a highway bridge using project drawings and an analytical modal analysis is then performed to generate natural frequencies and mode shapes in the three orthogonal directions. The ambient vibration measurements are carried out on the bridge deck under natural excitation such as traffic, human walking and wind loads using Operational Modal Analysis. Sensitive seismic accelerometers are used to collect signals obtained from the experimental tests. To obtain experimental dynamic characteristics, two output-only system identification techniques are employed namely, Enhanced Frequency Domain Decomposition technique in the frequency domain and Stochastic Subspace Identification technique in time domain. Analytical and experimental dynamic characteristic are compared with each other and finite element model of the bridge is updated by changing of boundary conditions to reduce the differences between the results. It is demonstrated that the ambient vibration measurements are enough to identify the most significant modes of highway bridges. After finite element model updating, maximum differences between the natural frequencies are reduced averagely from 23% to 3%. The updated finite element model reflects the dynamic characteristics of the bridge better, and it can be used to predict the dynamic response under complex external forces. It is also helpful for further damage identification and health condition monitoring. Analytical model of the bridge before and after model updating is analyzed using 1992 Erzincan earthquake record to determine the seismic behaviour. It can be seen from the analysis results that displacements increase by the height of bridge columns and along to middle point of the deck and main arches. Bending moments have an increasing trend along to first and last 50 m and have a decreasing trend long to the middle of the main arches.

Analysis of Slope Fracturing using a Terrestrial LiDAR (지상라이다를 이용한 사면파괴 거동분석)

  • Yoo, Chang-Ho;Choi, Yun-Soo;Kim, Jae-Myeong
    • Spatial Information Research
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    • v.16 no.3
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    • pp.279-290
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    • 2008
  • Landslide, one of the serious natural disasters, has Incurred a large loss of human and material resources. Recently, many forecasting or alarm systems based on various kinds of measuring equipment have been developed to reduce the damage of landslide. However, only a few of these equipments are guaranteed to evaluate the safety of whole side of land slope with their accessibility to the slope. In this study, we performed some experiments to evaluate the applicability of a terrestrial LiDAR as a surveying tool to measure the displacement of a land slope surface far a slope collapsing protection system. In the experiments, we had applied a slope stability method to a land slope and then forced to this slope with a load increasing step by step. In each step, we measured the slope surface with both a total station and a terrestrial LiDAR simultaneously. As the result of Slope Fracturing analysis using all targets, the LiDAR system showed that three was 1cm RMSE on X-axis, irregularity errors on Y-axis and few errors on Z-axis compare with Total Station. As the result of Slope Fracturing analysis using continuous targets, the pattern of Slope Fracturing was different according to the location of continuous targets and we could detect a continuous change which couldn't be found using Total station. The accuracy of the LiDAR data was evaluated to be comparable to that of the total station data. We found that a LiDAR system was appropriate to measuring the behaviour of land slope. The LiDAR data can cover the whole surface of the land slope, whereas the total station data are available on a small number of targets. Moreover, we extracted more detail information about the behavior of land slope such as the volume and profile changes using the LiDAR data.

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Seasonal and Elevational Pattern of Herbivore's Feeding Activity in Temperate Deciduous Forest (온대낙엽수림에서 초식곤충의 계절과 고도에 따른 먹이활동 양상 연구)

  • Kim, Nang-Hee;Choi, Sei-Woong
    • Korean Journal of Ecology and Environment
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    • v.47 no.1
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    • pp.24-31
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    • 2014
  • This study was conducted to clarify the seasonal and elevational pattern of herbivore's feeding pattern in a temperate deciduous forest. We investigated the herbivore's feeding activity for three years (2011~2013) at three survey sites in Mt. Jirisan National Park (Piagol, Siamjae, Nogodan). We selected target tree species based on the dominance across the sites (Quercus, Acer, Rhododendron and Carpinus) and scored herbivore's feeding activity every one or two weeks from April to June using leaf damage index. We found that the herbivory started early at the low elevation site (Piagol, ${\approx}300m$), and the highest feeding activity occurred at the mid elevation site (Siamjae, ${\approx}900m$). At the highest elevation site (Nogodan, ${\approx}1300m$), the herbivory started late, but the total feeding activity accumulated quickly. Compared to the breeding time of Varied tit, an insectivore bird, it was overlapped with the feeding activity period of herbivores, suggesting close interaction among plants, insects and birds in this deciduous forest. We suggested a need of long-term monitoring of this tri-trophic interaction since duration of herbivore activity can be changed followed by climate change.

Evaluation of Deterioration of Larix kaempferi Wood Heat-treated by Superheated Steam through Field Decay Test for 12 Months (12개월 야외 내후성 시험에 의한 과열증기 열처리된 낙엽송재의 열화 평가)

  • Park, Yonggun;Han, Yeonjung;Park, Jun-Ho;Chung, Hyunwoo;Kim, Hyunbin;Yang, Sang-Yun;Chang, Yoon-Seong;Yeo, Hwanmyeong
    • Journal of the Korean Wood Science and Technology
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    • v.46 no.5
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    • pp.497-510
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    • 2018
  • In this study, the decay resistance of larch wood, which was heat treated by superheated steam, was evaluated by the field decay test. During the field decay test of 12 months, non-treated wood has been severely damaged by termite, however, no visible damage has occurred in the preservative-treated wood and superheated steam heat-treated wood. Results of field decay test showed approximately 5% mass loss of the non-treated wood and the preservative-treated wood, and approximately 1% mass loss of the superheated steam heat-treated wood. After the field decay test for 12 months, the residual amount of preservatives remaining in the preservative-treated wood was lower than that before the field decay test. It was considered that the preservative was partially eluted during the field decay test, and the mass loss of the preservative-treated wood was thought to be similar to that of the non-treated wood. Through this study and additional long-term monitoring test, superheated steam heat treatment can be considered to be an environmental-friendly method to enhance the decay resistance of wood against rot fungi and/or insect without chemical treatment such as preservative injection.

Bleeding characteristics of coupling materials for installation of acoustic emission (AE) sensor (AE 센서 설치를 위한 커플링 재료의 블리딩 특성)

  • Lee, Jong-Won;Kim, Hyunwoo;Kim, Min-Koan;Oh, Tae-Min
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.19 no.4
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    • pp.635-650
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    • 2017
  • Acoustic emission (AE) sensors have broadly used to monitor the damage of underground structures and tunnels. The reliability of measured signal is determined by the coupling condition of the AE sensors which are embedded in the target underground structure. To secure the reliability of health monitoring results, it is important to understand the characteristics of the coupling materials. In this study, laboratory tests were performed using portland cement, micro cement, and gypsum as coupling materials in order to verify the bleeding characteristics. The effective parameters for bleeding were determined to be water-cement ratio, material type, curing time, and injected volume of coupling materials. As a results of the experimental study, the bleeding rate increases with an increase in a water-cement ratio and an injected volume; for portland cement, water-cement ratio and injected volume effects are larger than the micro cement. However, curing time is not much effective for occurrence of the bleeding phenomenon. It is anticipated that this study may be useful for the selection of suitable coupling materials for installation of acoustic emission sensors.

Are Biomarkers Predictive of Anthracycline-Induced Cardiac Dysfunction?

  • Malik, Abhidha;Jeyaraj, Pamela Alice;Calton, Rajneesh;Uppal, Bharti;Negi, Preety;Shankar, Abhishek;Patil, Jaineet;Mahajan, Manmohan Kishan
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.4
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    • pp.2301-2305
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    • 2016
  • Background: The early detection of anthracycline- induced cardiotoxicity is very important since it might be useful in prevention of cardiac decompensation. This study was designed with the intent of assessing the usefulness of cardiac troponin T (cTnT) and NT- Pro BNP estimation in early prediction of anthracycline induced cardiotoxicity. Materials and Methods: In this prospective study histologically proven breast cancer patients who were scheduled to receive anthracycline containing combination chemotherapy as a part of multimodality treatment were enrolled. Baseline cardiac evaluation was performed by echocardiography (ECHO) and biomarkers like cardiac troponin T (cTnT) and N terminal- pro brain natriuretic peptide (NT- Pro BNP). All patients underwent cTnT and NT- Pro BNP estimation within 24 hours of each cycle of chemotherapy and were followed up after 6 months of initiation of chemotherapy. Any changes in follow up ECHO were compared to ECHO at baseline and cTnT and NT- Pro BNP levels after each cycle of anthracycline-based chemotherapy. Results: Initial data were obtained for 33 patients. Mean change in left ventricular diastolic diameter (LVDD) within 6 months was $0.154{\pm}0.433cms$ (p value=0.049). Seven out of 33 patients had an increase in biomarker cTnT levels (p value=0.5). A significant change in baseline and follow up LVDD was observed in patients with raised cTnT levels (p value=0.026) whereas no change was seen in ejection fraction (EF) and left atrial diameters (LAD) within 6 months of chemotherapy. NT- Pro BNP levels increased in significant number of patients (p value ${\leq}0.0001$) but no statistically significant change was observed in the ECHO parameters within 6 months. Conclusions: Functional monitoring is a poorly effective method in early estimation of anthracycline induced cardiac dysfunction. Estimation of biomarkers after chemotherapy may allow stratification of patients in various risk groups, thereby opening window for interventional strategies in order to prevent permanent damage to the myocardium.

35-Year Research History of Cytotoxicity and Cancer: a Quantitative and Qualitative Analysis

  • Farghadani, Reyhaneh;Haerian, Batoul Sadat;Ebrahim, Nader Ale;Muniandy, Sekaran
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.7
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    • pp.3139-3145
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    • 2016
  • Cancer is the leading cause of morbidity and mortality worldwide, characterized by irregular cell growth. Cytotoxicity or killing tumor cells that divide rapidly is the basic function of chemotherapeutic drugs. However, these agents can damage normal dividing cells, leading to adverse effects in the body. In view of great advances in cancer therapy, which are increasingly reported each year, we quantitatively and qualitatively evaluated the papers published between 1981 and December 2015, with a closer look at the highly cited papers (HCPs), for a better understanding of literature related to cytotoxicity in cancer therapy. Online documents in the Web of Science (WOS) database were analyzed based on the publication year, the number of times they were cited, research area, source, language, document type, countries, organization-enhanced and funding agencies. A total of 3,473 publications relevant to the target key words were found in the WOS database over 35 years and 86% of them (n=2,993) were published between 2000-2015. These papers had been cited 54,330 times without self-citation from 1981 to 2015. Of the 3,473 publications, 17 (3,557citations) were the most frequently cited ones between 2005 and 2015. The topmost HCP was about generating a comprehensive preclinical database (CCLE) with 825 (23.2%) citations. One third of the remaining HCPs had focused on drug discovery through improving conventional therapeutic agents such as metformin and ginseng. Another 33% of the HCPs concerned engineered nanoparticles (NPs) such as polyamidoamine (PAMAM) dendritic polymers, PTX/SPIO-loaded PLGAs and cell-derived NPs to increase drug effectiveness and decrease drug toxicity in cancer therapy. The remaining HCPs reported novel factors such as miR-205, Nrf2 and p27 suggesting their interference with development of cancer in targeted cancer therapy. In conclusion, analysis of 35-year publications and HCPs on cytotoxicity in cancer in the present report provides opportunities for a better understanding the extent of topics published and may help future research in this area.

Seasonal Prevalence and Integrated Control Method of Insect Pests in the Dredged Soil Dumping Area in Masan, Korea (마산시 준설토 투기장에서 발생하는 유해곤충의 계절적 발생 소장과 통합적 저감방법)

  • Kim, Yong-Ki;Lee, Cheol-Min;Bae, Yang-Seop
    • Journal of Wetlands Research
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    • v.14 no.4
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    • pp.687-698
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    • 2012
  • This study was conducted to monitor and prevent outbreak of insect pestsin dredged soil dumping area after completion of dredging construction in Masan City. Monitoring was carried out using tent trap, colored sticky trap, and CDC light trap. A total of 217,073 individuals belonging to 23 species from 10 families in 3 orders were collected. In overwintering survey using tent trap, 3 species were collected. 2 species (Leptocera fuscipennis (Haliday) and Ephydra japonica Miyagi) of them were outbreak species. In color sticky trap, more than 96% of total individuals were comprised of five species: Urolepis maritima Walker (43%), E. japonica (19%), Fucellia sp. 1 (13%), Philotelma sp. 1 (10%), and Homalometopus sp. 1 (9%). In CDC light trap, three dominant species were Homalometopus sp. 1 (91%), Glyptotendipes tokunagai Sasa (6%), and L. fuscipennis (1%), representing about 98% of the total. To prevent damage caused by outbreak of insect pests, we carried out ecological control methods such as covering the fresh soil in outbreak area, using light trap, pumping up water and so on, minimizing use of thermal fogging and insect growth regulatorwhen the insect pest population was rapidly increasing.