• Journal of Korean Society on Water Environment
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• v.27 no.5
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• pp.699-709
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• 2011

The uses of multi-dimensional hydrodynamic and water quality models are increasing to support a sustainable management of large dam reservoirs in Korea. Any modeling study requires selection of a proper spatial dimension of the model based on the characteristics of spatial variability of concerned simulation variables. For example, a laterally averaged two-dimensional (2D) model, which has been widely used in many large dam reservoirs in Korea, assumes that the lateral variations of hydrodynamic and water quality variables are negligible. However, there has been limited studies to give a justification of the assumption. The objectives of this study were to present the characteristics of spatial variations of water quality variables through intensive field monitoring in Daechung Reservoir, and provide information on a proper spatial dimension for different water quality parameters. The monitoring results showed that the lateral variations of water temperature are marginal, but those of DO, pH, and conductivity could be significant depending on the hydrological conditions and local algal biomass. In particular, the phytoplankton (Chl-a) and nutrient concentrations showed a significant lateral variation at R2 (Daejeongri) during low flow periods in 2008 possibly because of slow lateral mixing of tributary inflow from So-oak Stream and wind driven patchiness.

• Journal of Korea Society of Waste Management
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• v.35 no.8
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• pp.777-784
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• 2018

Since climate change increases the risk of extreme rainfall events, concerns on flood management have also increased. In order to rapidly recover from flood damages and prevent secondary damages, fast collection and treatment of flood debris are necessary. Therefore, a quick and precise estimation of flood debris generation is a crucial procedure in disaster management. Despite the importance of debris estimation, methodologies have not been well established. Given the intrinsic heterogeneity of flood debris from local conditions, a regional-scale model can increase the accuracy of the estimation. The objectives of this study are 1) to identify significant damage variables to predict the flood debris generation, 2) to ascertain the difference in the coefficients, and 3) to evaluate the accuracy of the debris estimation model. The scope of this work is flood events in Ulsan city region during 2008-2016. According to the correlation test and multicollinearity test, the number of damaged buildings, area of damaged cropland, and length of damaged roads were derived as significant parameters. Key parameters seems to be strongly dependent on regional conditions and not only selected parameters but also coefficients in this study were different from those in previous studies. The debris estimation in this study has better accuracy than previous models in nationwide scale. It can be said that the development of a regional-scale flood debris estimation model will enhance the accuracy of the prediction.

• Journal of Environmental Health Sciences
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• v.47 no.3
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• pp.227-244
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• 2021

Objectives: The Korean National Environmental Health Survey provides representative biomonitoring data for environmental pollutants in South Korea. Over the last decade, there have been various studies published using this data. In this study, we aimed to provide information and implications by reviewing each study. Methods: We searched comprehensive electronic databases from PubMed, Google Scholar, and Naver Academic database using the key words 'Korean National Environmental Health Survey' and 'KoNEHS' through March 2021. A total of 57 studies were selected after reviewing the relevance of the data. Results: The most frequently studied pollutants were heavy metals (10), Cotinine (8), Bisphenol A (7), and Phthalates (6), in that order. In particular, Phthalates, Bisphenol A, and Parabens were often studied together (6). A decline in urinary cotinine and heavy metals in the body was shown over time among studies on exposure association. It was demonstrated that Phthalates and Bisphenol A were significantly related to obesity and diabetes from the studies of health impacts. Cross-section study design, spot urine, and insufficient health status information were mostly reported as limitations of the data. Conclusion: Since research has been focused on adults, further investigations of children and adolescents are required. In this regard, it is necessary to maintain the consistency of the data structure and provide integrated weights for all ages. In addition, it would allow the measurement of several environmental pollutants by considering subsample design. Lastly, integrated studies with multi-cycles and the health effects from co-exposure to multiple chemicals would be expected to provide important knowledge.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.1
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• pp.25-33
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• 2021

Objectives: Many conditions of the oral and maxillofacial region require hospitalization and in-patient care. The average length of stay (LOS) of these patients varies and is usually affected by multiple confounding variables. However, even with an increasing number of hospital admissions, published evidence on the factors that affect the LOS of oral and maxillofacial patients is lacking. Therefore, this study assessed the LOS of in-patients at the oral and maxillofacial surgery department of a government-funded, multi-specialty hospital in Malaysia, based on their reasons for admission and other factors. Materials and Methods: Our samples were collected retrospectively over a 5-year period and included patients with maxillofacial infections, post-trauma stabilization, facial bone fracture surgery, benign and malignant lesion surgery, dentoalveolar surgery, and other maxillofacial surgeries as reasons for admission. Factors potentially affecting LOS were also recorded, and their significance was determined using multiple logistic regression analyses. A P-value of less than 0.05 was considered to be statistically significant. Results: A total of 1,380 patients were included in this study. Most (84.5%) of our in-patients were of Malay ethnicity, and males outnumbered females in our sample by 502 subjects. The median LOS of our in-patients was 3 days. Sex, ethnicity, age, reason for admission, and American Society of Anesthesiology (ASA) classification were factors that significantly affected LOS. Conclusion: The median LOS reported in this study was 3 days. LOS was significantly affected by sex, ethnicity, age, reason of admission and ASA classification.

• Journal of Environmental Health Sciences
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• v.47 no.4
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• pp.330-338
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• 2021

Background: This study was conducted to provide background information for the proper management of radon contamination in apartments using mechanical ventilation facilities in residential environments. Objectives: To this end, this study compared and evaluated changes in radon concentrations based on different operating intensities of mechanical ventilation with or without natural ventilation. Methods: For the continuous measurement of radon concentrations, an RAD7 instrument was installed in four apartments equipped with a ventilation system. The measurements were done for comparison of ventilation types and different ventilation intensities ("high", "middle", "low"). Results: The results confirmed that both mechanical and natural ventilation sufficiently reduced the radon concentration in the apartments. In particular, mechanical ventilation at "high" intensity was the most effective. Natural ventilation combined with mechanical ventilation and then natural ventilation alone were the second and the third most effective, respectively. Conclusions: When using ventilation to reduce indoor radon concentrations, it is most effective to operate mechanical ventilation ("high") or natural ventilation and mechanical ventilation at the same time. In cases where mechanical ventilation is available alone, it is recommended to operate it at a minimum of "middle" intensity.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.6
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• pp.438-444
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• 2021

Objectives: Loss of the interdental papilla is multi-factorial and creates a multitude of problems. Autogenous connective tissue/biomaterial-based regeneration has been attempted for decades to reconstitute the black space created due to the loss of papilla. The aim of this present study was to regenerate papillary recession defects using an amnion-chorion membrane (ACM) allograft and to evaluate the clinical outcome up to six months postoperatively. Materials and Methods: Twenty patients with 25 Nordland and Tarnow's Class I/II interdental papillary recession defects were treated with ACM and coronal advancement of the gingivo-papillary unit via a semilunar incision on the labial aspect followed by a sulcular incision in the area of interest. A photographic image analysis was carried out using the GNU Image Manipulation software program from the baseline to three and six months postoperatively. The black triangle height (BTH) and the black triangle width (BTW) were calculated using the pixel size and were then converted into millimeters. The mean and standard deviation values were determined at baseline and then again at three and six months postoperatively. The probability values (P<0.05 and P≤0.01) were considered statistically significant and highly significant, respectively. An analysis of variance and post hoc Bonferroni test were carried out to compare the mean values. Results: Our evaluation of the BTH and BTW showed a statistically and highly significant difference from the baseline until both three and six months postoperatively (P=0.01). A post hoc Bonferroni test disclosed a statistically significant variance from the baseline until three and six months postoperatively (P<0.05) and a non-significant difference from three to six months after the procedure (P≥0.05). Conclusion: An ACM allograft in conjunction with a coronally advanced flap could be a suitable minimally invasive alternative for papillary regeneration.

• Korean Journal of Acupuncture
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• v.38 no.4
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• pp.267-274
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• 2021

Objectives : Acupoints education is important in that it can determine the clinical competency of Korean Medicine Doctors (KMDs). Accordingly, we aimed to develop a practical simulator for acupoints education, acupoints training, acupoints practice, and acupoints evaluation. Methods : Korean Medicine (KM) SMART Table can be divided into hardware, server and components, and is organically linked. We develop KM SMART Table that combines the hardware of a human-sized table with a UHD display capable of multi-touch in two cases and software that can teach acupoints. We make Augmented Reality (AR) contents linked with KM SMART Table contents and develop applications that can use contents using mobile devices. By developing an AR image tracking module to react with KM SMART Table, it enables acupoint learning according to the mobile device platform and human anatomy. Results : The current system is a prototype where some 3D technology has been implemented, but the AR function will be produced later. New learning using 3D and AR will be required during acupoints education and acupoints practice. It will be used a lot in OSCE (Objective Structured Clinical Examination) practices for strengthening the competency of KMDs, and it will be of great help not only in KM education as a unique simulator of KM, but also in the practice of acupuncture and chuna for musculoskeletal diseases. Conclusions : The KM SMART Table is a technology that combines 3D and AR to learn acupoints, and to conduct acupoints OSCE practice, and we suggest that it can be usefully used for educational evaluation.

• Journal of Preventive Medicine and Public Health
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• v.55 no.1
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• pp.68-79
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• 2022

Objectives: This study investigated associations between ethnicity and malaria awareness in East Nusa Tenggara Province (ENTP), Indonesia. Methods: A community-based cross-sectional study was conducted upon 1503 adults recruited by multi-stage cluster random sampling. A malaria awareness questionnaire was used to collect data, according to which participants were classified as aware or unaware of malaria. Logistic regression was applied to quantify the strength of associations of factors with malaria awareness. Results: The participation rate in this study was high (99.5%). The participants were distributed relatively evenly among the Manggarai, Atoni, and Sumba ethnicities (33.0, 32.3, and 30.2%, respectively). Malaria awareness was significantly different amongst these groups; it was most common in the Manggarai ethnicity (65.1%; 95% confidence interval [CI], 59.9 to 70.3) and least common in the Sumba ethnicity (35.0%; 95% CI, 27.6 to 42.4). The most prominent factor influencing the malaria awareness in the Sumba and Manggarai ethnicities was education level, whilst it was socioeconomic status (SES) in the Atoni ethnicity. The likelihood of malaria awareness was significantly higher in adults with an education level of diploma or above (adjusted odds ratio [aOR], 21.4; 95% CI, 3.59 to 127.7 for Manggarai; aOR, 6.94; 95% CI, 1.81 to 26.6 for Sumba). Malaria awareness was significantly more common amongst high-SES adults in the Atoni group (aOR, 24.48; 95% CI, 8.79 to 68.21). Conclusions: Low education levels and low SES were prominent contributors to lower levels of malaria awareness in rural ENTP. Interventions should focus on improving malaria awareness to these groups to support the Indonesian government's national commitment to achieve a malaria elimination zone by 2030.

• Journal of Veterinary Science
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• v.21 no.5
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• pp.75.1-75.8
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• 2020

Background: Dental diseases are common in dogs and cats, and accurate measurements of dentoalveolar structure are important for planning of treatment. The information that the comparison computed tomography (CT) with dental radiography (DTR) is not yet reported in veterinary medicine. Objectives: The purpose of this study was to compare the DTR with CT of dentoalveolar structures in healthy dogs and cats, and to evaluate the CT images of 2 different slice thicknesses (0.5 and 1.0 mm). Methods: We included 6 dogs (2 Maltese and 1 Spitz, Beagle, Pomeranian, mixed, 1 to 8 years, 4 castrated males, and 2 spayed female) and 6 cats (6 domestic short hair, 8 months to 3 years, 4 castrated male, and 2 spayed female) in this study. We measured the pulp cavity to tooth width ratio (P/T ratio) and periodontal space of maxillary and mandibular canine teeth, maxillary fourth premolar, mandibular first molar, maxillary third premolar and mandibular fourth premolar. Results: P/T ratio and periodontal space in the overall dentition of both dogs and cats were smaller in DTR compared to CT. In addition, CT images at 1.0 mm slice thickness was generally measured to be greater than the images at 0.5 mm slice thickness. Conclusions: The results indicate that CT with thin slice thickness provides more accurate information on the dentoalveolar structures. Additional DTR, therefore, may not be required for evaluating dental structure in small-sized dogs and cats.

• Journal of Veterinary Science
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• v.23 no.6
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• pp.68.1-68.8
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• 2022

Background: Studies on anesthetized dogs regarding pulse pressure variation (PPV) are increasing. The influence of respiratory rate (RR) on PPV, in mechanically ventilated dogs, has not been clearly identified. Objectives: This study evaluated the influence of RR on PPV in mechanically ventilated healthy dogs after hemorrhage. Methods: Five healthy adult Beagle dogs were premedicated with intravenous (IV) acepromazine (0.01 mg/kg). Anesthesia was induced with alfaxalone (3 mg/kg IV) and maintained with isoflurane in 100% oxygen. The right dorsal pedal artery was cannulated with a 22-gauge catheter for blood removal, and the left dorsal pedal artery was cannulated and connected to a transducer system for arterial blood pressure monitoring. The PPV was automatically calculated using a multi-parameter monitor and recorded. Hemorrhage was induced by withdrawing 30% of blood (24 mL/kg) over 30 min. Mechanical ventilation was provided with a tidal volume of 10 mL/kg and a 1:2 inspiration-to-expiration ratio at an initial RR of 15 breaths/min (baseline). Thereafter, RR was changed to 20, 30, and 40 breaths/min according to the casting lots, and the PPV was recorded at each RR. After data collection, the blood was transfused at a rate of 10 mL/kg/h, and the PPV was recorded at the baseline ventilator setting. Results: The data of PPV were analyzed using the Friedman test followed by the Wilcoxon signed-rank test (p < 0.05). Hemorrhage significantly increased PPV from 11% to 25% at 15 breaths/min. An increase in RR significantly decreased PPV from 25 (baseline) to 17%, 10%, and 10% at 20, 30, and 40 breaths/min, respectively (all p < 0.05). Conclusions: The PPV is a dynamic parameter that can predict a dog's hemorrhagic condition, but PPV can be decreased in dogs under high RR. Therefore, careful interpretation may be required when using the PPV parameter particularly in the dogs with hyperventilation.