• Title/Summary/Keyword: Concern Assessment

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Total reference-free displacements for condition assessment of timber railroad bridges using tilt

  • Ozdagli, Ali I.;Gomez, Jose A.;Moreu, Fernando
    • Smart Structures and Systems
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    • v.20 no.5
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    • pp.549-562
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    • 2017
  • The US railroad network carries 40% of the nation's total freight. Railroad bridges are the most critical part of the network infrastructure and, therefore, must be properly maintained for the operational safety. Railroad managers inspect bridges by measuring displacements under train crossing events to assess their structural condition and prioritize bridge management and safety decisions accordingly. The displacement of a railroad bridge under train crossings is one parameter of interest to railroad bridge owners, as it quantifies a bridge's ability to perform safely and addresses its serviceability. Railroad bridges with poor track conditions will have amplified displacements under heavy loads due to impacts between the wheels and rail joints. Under these circumstances, vehicle-track-bridge interactions could cause excessive bridge displacements, and hence, unsafe train crossings. If displacements during train crossings could be measured objectively, owners could repair or replace less safe bridges first. However, data on bridge displacements is difficult to collect in the field as a fixed point of reference is required for measurement. Accelerations can be used to estimate dynamic displacements, but to date, the pseudo-static displacements cannot be measured using reference-free sensors. This study proposes a method to estimate total transverse displacements of a railroad bridge under live train loads using acceleration and tilt data at the top of the exterior pile bent of a standard timber trestle, where train derailment due to excessive lateral movement is the main concern. Researchers used real bridge transverse displacement data under train traffic from varying bridge serviceability levels. This study explores the design of a new bridge deck-pier experimental model that simulates the vibrations of railroad bridges under traffic using a shake table for the input of train crossing data collected from the field into a laboratory model of a standard timber railroad pile bent. Reference-free sensors measured both the inclination angle and accelerations of the pile cap. Various readings are used to estimate the total displacements of the bridge using data filtering. The estimated displacements are then compared to the true responses of the model measured with displacement sensors. An average peak error of 10% and a root mean square error average of 5% resulted, concluding that this method can cost-effectively measure the total displacement of railroad bridges without a fixed reference.

Vascular Plant Diversity of Jeju Island, Korea

  • Kim, Chan-Soo
    • Korean Journal of Plant Resources
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    • v.22 no.6
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    • pp.558-570
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    • 2009
  • The vascular plants in Jeju composed of 21 families 62 genera, 190 species, 7 varieties with 197 taxa in Pteridophyta, 3 families 5 genera, 7 species, 3 forma with 10 taxa in gymnosperm (Coniferophyta) and 143 families 703 genera, 1,622 species, 114 varieties and 47 forma with 1,783 taxa in Endospermae. The total number of taxa was 1,990 consisting 167 families, 770 genera, 1,818 species, 121 varieties and 50 forma. Three families, 4 genera 4 species and 1 variety in Pteridophyta and 1 family, 1 genus I species, 1 forma of Coniferophyta were endemic to Jeju. Five families, 8 genera and 8 species in the Monocotyledonae of Endospermae and 23 families, 32 genera, 21 species, 16 varieties and 7 forma and 44 taxa in Cholipetalae, and 9 families, 24 genera, 12 species, 13 varieties and 7 forma, total 32 taxa in Sympetalae were endemic to Jeju. Total 90 taxa with 41 families, 69 genera, 46 species, 29 varieties and 15 forma were drawn up as endemic plants in Jeju. As the numbers show on, Jeju has more biodiversity especially plant diversity than any other places in Korea. It was an important region in regard to geographical position. The rarity on plants from Jeju has been assessed based on the IUCN red list categories and criteria at both regional and global levels. There was one species in each extinct (EX) and extinct in the Wild (EW). The EX and EW species were Rhododendron saisiuense Nakai (Ericaceae) and Asplenium antiquum Makino (Aspleniaceae), respectively. Three taxa, Rhododendron dauricum L. (Ericaceae), Lycopodium sieboldii Miq., and Lycopodiella cernua (L.) Serm (Lycopodiaceae) were species that is extinct in the region (RE). Sixty-one taxa were critically endangered (CR), 13 were endangered (EN), and 83 were vulnerable (VU) at regional level. The taxa listed on a Red List corresponds 26.9% of total taxa in Jeju. At global level, there were 19 taxa in CR, 4 in EN, and 1 in VU (Vulnerable) as the category of threat. The rest taxa (133 taxa) were classified as Least Concern (LC). According to the results of the assessment, conservation measures must be taken for total of 157 species that were categorized in threaten including one of EX, one of EW and three extinct in the region immediately. Of 157 species, 61 were CR, 13 are EN and 83 were VU.

A Study on dental hygienist subjectivity toward relationship with inaccessible patients: the cases of Seoul, Gyeonggi province and Incheon (치과위생사가 경험한 어려운 환자와의 관계에 대한 주관성 연구 -서울, 경기, 인천 지역을 중심으로-)

  • Han, Kyung-Soon;Kim, Young-Nam;Lee, Myeong-Ju
    • Journal of Korean society of Dental Hygiene
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    • v.5 no.2
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    • pp.279-296
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    • 2005
  • The purpose of this study was to examine what types of experiences dental hygienists underwent with patients who were unapproachable in an effort to find out the latter group's needs and expectations, explore how to treat them of different personality type, and provide better dental services in response to their needs. To attain the purpose, Q-methodology was employed, which made a subjective and systematic assessment of human subjectivity. There were three types of subjectivity among dental hygienists in conjunction with their experiences with patients who were hard to please. Each group whose subjectivity was different also had a different preference for patients, which was not exclusive to one another but unique. Type 1 was "avoiding patients who showed off". Dental hygienists of this type found it unpleasant to treat patients who boasted of their background, position or relations with the head of hospital and wanted to be given special treatment. They avoided those patients, since giving special treatment to specific patients was likely to do damage to others. They believed that better medical services could be provided through mutual concern and good manners between medical personnels and patients. Dental hygienists of type 2 considered it hard to treat patients who were picky and looked at treatment or its outcome negatively. Those who had to be separated from others on account of possible cross-infection or who called for special decontamination methods of dental instruments were also difficult to deal with. Dental hygienists of this type could be said to "avoid picky patients", as they preferred to fare with patients by offering good, faithful treatment rather than by giving special treatment. Dental hygienists of type 3 believed that smooth and successful treatment hinged on mutual trust, confidence and collaboration between medical personnels and patients. According to them, patients who choose a specific hospital or a particular medical team at their own option have to cooperate if necessary, listen carefully to medical personnels and treat them without any hostility or bias. Therefore, they could be said to "avoid patients who were not cooperative".

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Does Breast Cancer Drive the Building of Survival Probability Models among States? An Assessment of Goodness of Fit for Patient Data from SEER Registries

  • Khan, Hafiz;Saxena, Anshul;Perisetti, Abhilash;Rafiq, Aamrin;Gabbidon, Kemesha;Mende, Sarah;Lyuksyutova, Maria;Quesada, Kandi;Blakely, Summre;Torres, Tiffany;Afesse, Mahlet
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.12
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    • pp.5287-5294
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    • 2016
  • Background: Breast cancer is a worldwide public health concern and is the most prevalent type of cancer in women in the United States. This study concerned the best fit of statistical probability models on the basis of survival times for nine state cancer registries: California, Connecticut, Georgia, Hawaii, Iowa, Michigan, New Mexico, Utah, and Washington. Materials and Methods: A probability random sampling method was applied to select and extract records of 2,000 breast cancer patients from the Surveillance Epidemiology and End Results (SEER) database for each of the nine state cancer registries used in this study. EasyFit software was utilized to identify the best probability models by using goodness of fit tests, and to estimate parameters for various statistical probability distributions that fit survival data. Results: Statistical analysis for the summary of statistics is reported for each of the states for the years 1973 to 2012. Kolmogorov-Smirnov, Anderson-Darling, and Chi-squared goodness of fit test values were used for survival data, the highest values of goodness of fit statistics being considered indicative of the best fit survival model for each state. Conclusions: It was found that California, Connecticut, Georgia, Iowa, New Mexico, and Washington followed the Burr probability distribution, while the Dagum probability distribution gave the best fit for Michigan and Utah, and Hawaii followed the Gamma probability distribution. These findings highlight differences between states through selected sociodemographic variables and also demonstrate probability modeling differences in breast cancer survival times. The results of this study can be used to guide healthcare providers and researchers for further investigations into social and environmental factors in order to reduce the occurrence of and mortality due to breast cancer.

MODFLOW or FEFLOW: A Case Study of Groundwater Model Selection for the Upper Waikato Catchment, New Zealand

  • Weir, Julian;Moore, Dr Catherine;Hadfield, John
    • Proceedings of the Korea Water Resources Association Conference
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    • 2011.05a
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    • pp.14-14
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    • 2011
  • Groundwater in the Waikatoregion is a valuable resource for agriculture, water supply, forestry and industries. The 434,000 ha study area comprises the upper Waikato River catchment from the outflow of Lake Taupo (New Zealand's largest lake) through to Lake Karapiro (a man-made hydro lake with high recreational value) (Figure 1). Water quality in the area is naturally high. However, there are indications that this quality is deteriorating as a result of land use intensification and deforestation. Compounding this concern for decision makers is the lag time between land use changes and the realisation of effects on groundwater and surface water quality. It is expected that the effects of land use changes have not yet fully manifested, and additional intensification may take decadesto fully develop, further compounding the deterioration. Consequently, Environment Waikato (EW) have proposed a programme of work to develop a groundwater model to assist managing water quality and appropriate policy development within the catchment. One of the most important and critical decisions of any modelling exercise is the choice of the modelling platform to be used. It must not inhibit future decision making and scenario exploration and needs to allow as accurate representation of reality as feasible. With this in mind, EW requested that two modelling platforms, MODFLOW/MT3DMS and FEFLOW, be assessed for their ability to deliver the long-term modelling objectives for this project. The two platforms were compared alongside various selection criteria including complexity of model set-up and development, computational burden, ease and accuracy of representing surface water-groundwater interactions, precision in predictive scenarios and ease with which the model input and output files could be interrogated. This latter criteria is essential for the thorough assessment of predictive uncertainty with third-party software, such as PEST. This paper will focus on the attributes of each modelling platform and the comparison of the two approaches against the key criteria in the selection process. Primarily due to the ease of handling and developing input files and interrogating output files, MODFLOW/MT3DMS was selected as the preferred platform. Other advantages and disadvantages of the two modelling platforms were somewhat balanced. A preliminary regional groundwater numerical model of the study area was subsequently constructed. The model simulates steady state groundwater and surface water flows using MODFLOW and transient contaminant transport with MT3DMS, focussing on nitrate nitrogen (as a conservative solute). Geological information for this project was provided by GNS Science. Professional peer review was completed by Dr. Vince Bidwell (of Lincoln Environmental).

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Arsenic species in husked and polished rice grains grown at the non-contaminated paddy soils in Korea (국내 비오염 논토양에서 재배한 현미와 백미 중 비소화학종 함량)

  • Kim, Da-Young;Kim, Ji-Young;Kim, Kye-Hoon;Kim, Kwon-Rae;Kim, Hyuck-Soo;Kim, Jeong-Gyu;Kim, Won-Il
    • Journal of Applied Biological Chemistry
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    • v.61 no.4
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    • pp.391-395
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    • 2018
  • There is an increasing concern over arsenic (As) contamination of paddy soil and rice with regard to food safety. This study was conducted to investigate total and inorganic As concentration in one hundred husked and polished rice samples collected at the non-contaminated paddy soil in Korea. Arsenic species in rice samples were extracted using 1% nitric acid ($HNO_3$) with a microwave oven and were measured using high performance liquid chromatography coupled with inductively coupled plasma-mass spectrometry. Mean concentrations of total As in husked rice and polished rice were 0.18 and $0.11mg\;kg^{-1}$, respectively. Also, average inorganic As concentrations in husked rice and polished rice were 0.11 and $0.07mg\;kg^{-1}$, respectively. These levels are lower than the standard guideline value 0.35 and $0.2mg\;kg^{-1}$ for inorganic As in husked and polished rice recommended by Codex Committee on Contaminants in Foods and Ministry of Food and Drug Safety, respectively. The mean of the inorganic As ratio for the total amount of As was 0.65 and 0.67 for husked rice and polished rice, respectively, and the range was from 0.08 to 1.0. For health risk assessment, the average value of cancer risk probability was $9.24{\times}10^{-5}$ and ranged from $2.30{\times}10^{-5}$ to $1.90{\times}10^{-5}$. Therefore, human exposure to As through dietary intake of surveyed rice samples might considered to be a low health risk.

Assessment of the level and identification of airborne molds by the type of water damage in housing in Korea (국내 주택에서 물 피해 유형에 따른 부유곰팡이 농도 수준 평가 및 동정 분석)

  • Lee, Ju Yeong;Hwang, Eun Seol;Lee, Jeong-Sub;Kwon, Myunghee;Chung, Hyen Mi;Seo, SungChul
    • Journal of odor and indoor environment
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    • v.17 no.4
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    • pp.355-361
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    • 2018
  • Mold grows more easily when humidity is higher in indoor spaces, and as such is found more often on wetted areas in housing such as walls, toilets, kitchens, and poorly managed spaces. However, there have been few studies that have specifically assessed the level of mold in the indoor spaces of water-damaged housing in the Republic of Korea. We investigated the levels of airborne mold according to the characteristics of water damage types and explored the correlation between the distribution of mold genera and the characteristics of households. Samplings were performed from January 2016 to June 2018 in 97 housing units with water leakage or condensation, or a history of flooding, and in 61 general housing units in the metropolitan and Busan area, respectively. Airborne mold was collected on MEA (Malt extract agar) at flow rate of 100 L/min for 1 min. After collection, the samples were incubated at $25^{\circ}C$ for 120 hours. The cultured samples were counted and corrected using a positive hole conversion table. The samples were then analyzed by single colony culture, DNA extraction, gene amplification, and sequencing. By type of housing, concentrations of airborne mold were highest in flooded housing, followed by water-leaked or highly condensed housings, and then general housing. In more than 50% of water-damaged housing, the level of airborne mold exceeded the guideline of Korea's Ministry of Environment ($500CFU/m^3$). Of particular concern was the fact that the I/O ratio of water-damaged housing was greater than 1, which could indicate that mold damage may occur indoors. The distribution patterns of the fungal species were as follows: Penicillium spp., Cladosporium spp. (14%), Aspergillus spp. (13%) and Alternaria spp. (3%), but significant differences of their levels in indoor spaces were not found. Our findings indicate that high levels of mold damage were found in housing with water damage, and Aspergillus flavus and Penicillium brevicompactum were more dominant in housing with high water activity. Comprehensive management of flooded or water-damaged housing is necessary to reduce fungal exposure.

Research Trends of Temperament and Character Inventory in Korean Journals Published from 1998 through 2018 (기질 및 성격 검사(Temperament and Character Inventory: TCI)의 국내 연구 동향: 1998-2018년 학술지 게재 논문을 중심으로)

  • Lee, Soo Jin;Kim, Min Jin;Shin, Hee Eun;Yeo, Jeong Mi;Jeong, Su Dong;Jung, Eun Jung;Chae, Han
    • The Journal of the Korea Contents Association
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    • v.21 no.10
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    • pp.537-549
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    • 2021
  • The purpose of the present study was to investigate the research trends of published articles in Korean journals dealing with Temperament and Character Inventory (TCI) from 1998 through 2018. A total of 185 papers were analyzed about an affiliation of corresponding author, type and dimension of TCI, and research contents considering the major publication regarding the Korean version of the TCI and major event in Korea. The results were as followed. First, most researchers belonged to university (53%) and hospital (44%). Second, both temperament and character dimensions (65%) were often used rather than temperament dimension only (34%). Third, regarding the subjects, adults (52%), children and adolescents (38%), and preschoolers (10%) appeared the most frequently used in the order. Fourth, we found that psychopathology (36%), personality (22%), health (16%), addiction (10%), assessment (8%) were the most popular areas of concern. Based on these results with the focus of analysis on the relationships between research subjects and research contents, implications and directions for future research and clinical settings regarding the treatment effect using the TCI character dimensions and diverse age groups were discussed.

Analysis on Trail Deterioration in Wolseong, Gyeongju-si - Focused on Assessing Impact Rating Class - (경주 월성의 산책로 훼손실태 분석 - 환경피해도 평가를 중심으로 -)

  • Kang, Tai-Ho;You, Ju-Han;Zhao, Hong-Xia;Li, Hong
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.29 no.3
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    • pp.33-39
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    • 2011
  • The purpose of this study is to present the raw data for establishing the conservation and restoration trail about Wolseong by objective and systematical trail deterioration in Wolseong as UNESCO, world heritage site, Gyeongju-si, Korea. To accomplish the purpose, not only trail condition such as altitude, entire width, bare width, maximum depth and slope of trail, but also deterioration types of trail were surveyed at the total 97 points for 2.145km in length on the 11 access trails to Wolseong. Major deterioration types of trail were root exposure(48%), rock exposure(40%), trail deeping(9%) in order of frequency. To grasp the deterioration condition of the trail, assessment on impact rating class of trail that the 11 access trail were investigated. Putting these results together informs us that the deterioration condition of the trail in Wolseong is reached the level of grave concern yet, prompt countermeasure to maintain the existing condition has to be considered with regard for the conditions of location and the containing amounts of use.

Assessment of the Caries Detection Ability of Quantitative Light-induced Fluorescence (QLF) in Primary Teeth in vitro (유치의 치아우식증 확인을 위한 정량형광분석(QLF) 검사법의 우식탐지능력 평가)

  • Cho, Kyung Hyun;Kang, Chung-Min;Jung, Hoi-In;Lee, Tae Yang;Song, Je Seon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.49 no.1
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    • pp.65-75
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    • 2022
  • The aim of this study was to evaluate QLF (quantitative light-induced fluorescence) technology for the caries detection in primary teeth and validate the relationships between the cavity volume of carious lesions and QLF analysis results. Total 125 tooth surfaces include 53 occlusal surfaces, and 72 proximal surfaces were investigated with the portable QLF device for detection of dental caries in primary molars. Micro-CT radiograph was also performed to classify carious lesions and calculate the cavity volume. QLF showed good accuracy and reliability (sensitivity 0.75 - 0.94, specificity 0.82 - 0.95, and AUROC 0.88 - 0.98) for the caries detection in primary teeth except 𝚫R average results of proximal caries which showed relatively low values. Statistically significant relationships were found between 𝚫F average, QS-Index and the cavity volume according to Spearman rank-order correlation coefficients (r = 0.805 - 0.832, p < 0.001). QLF detection method would be a harmless and reliable way for children to diagnose dental caries without the concern about radiation exposure.