• 한국환경보건학회지
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• 제38권1호
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• pp.31-41
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• 2012

Objectives: Biomonitoring is used to assess human environmental exposures. Urinary biomonitoring data are typically adjusted to a constant creatinine concentration to correct for variable dilutions among spot samples. Our objective was to investigate urinary creatinine concentrations by region, gender, age and lifestyle. Methods: We studied urinary creatinine concentrations in 6,286 Koreans aged 20 years old and older who participated the fourth Korea National Health and Nutrition Survey (KNHANES IV) in 2009. Urinary creatinine concentration analysis used the Jaffe method. Results: The average urinary creatinine concentration of 6,286 Koreans was 158.99 mg/dl. The urinary creatinine concentration was significantly higher among men (184.97 mg/dl) than women (130.02 mg/dl). In both men and women, urinary creatinine concentrations were significantly different according to age group (p < 0.01). Whereas the urinary creatinine concentration of men significantly differed with smoking in adjusted comparison analysis, that of women significantly differed by education level. Ninety-two percent of urinary creatinine concentration was included within WHO guidelines effective range(30 mg/dl ${\leq}$ urinary creatinine concentration ${\leq}$ 300 mg/dl). In multiple regression analysis, creatinine was influenced by gender, age and body mass index (BMI). Conclusions: The urinary creatinine value obtained from representative samples of adult Koreans aged 20 year and older in KNHANES IV 2009 could be used as a reference value for other nationally studied surveys, such as abandoned metal mine surveys and surveys for industrial complexes.

• 한국조사연구학회지:조사연구
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• 제11권2호
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• pp.161-176
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• 2010

본 논문은 학위논문에 사용된 여론조사 자료의 품질을 평가하였으며, 또한 학위논문에 사용되는 데이터의 품질평가 모형을 제시하였다. 데이터의 품질평가와 평가모형에 사용한 평가지표는 한국조사연구학회에서 제시한 조사윤리강령 제3조의 16가지 항목을 사용하였다. 연구결과 학위논문에 사용된 여론조사 데이터의 품질은 낮은 수준임을 확인할 수 있었다. 16개 항목별로 석 박사학위에 따른 유의적인 차이가 있는지를 확인하기 위하여 두 집단 간 비율 차이 검정을 실시한 결과 표집오차와 분석방법의 수에서만 차이가 있을 뿐 다른 지표에서는 차이가 나타나지 않았다. 끝으로 학위논문에 사용된 여론조사 자료의 질을 평가하기 위한 품질평가를 위해 9가지 주요 평가지표에 가중치를 부여하는 모형을 제시하였다.

• Toxicological Research
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• 제20권3호
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• pp.225-232
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• 2004

The suitability of the single cell gel electrophoresis (SCGE) assay as a test for the monitoring of genotoxicity of aquatic environment was evaluated. The SCGE assay was employed to detect DNA damage induced in clam (Spisula sachalinensis) exposed to a direct mutagen, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) or an indirect mutagen, benzo[a]pyrene (B[a]P). The cells of gill and digestive glands were isolated from clam by homogenization, which was the optimized cell dissociation method, and the level of DNA damage was assessed and expressed as mean tail length. In the gill cells, significant dose- and time-dependent increase was observed in the mean tail length at the concentration from 0.01 to 0.5 ppm MNNG for 96 h. The linear correlation between relative dam-age index (RDI) values was suggested to provide criteria of genotoxicity monitoring for direct acting mutagen. The dose- and time-dependent responses of the digestive glands cells were less sensitive than those of the gill cells. In contrast, the genotoxic response resulting from the exposure of 0.01～1.0 ppm B[a]P to clam revealed a higher sensitivity in the digestive glands cells than the gill cells. The comparison between the time profiles of genotoxic responses in clam and carp, the latter had been obtained in our previous study, indicated that the metabolism of genotoxic compounds in the two aquatic organisms were quite different each other. We conclude that the SCGE assay has the potential as a screening test for routine genotoxicity monitoring of aquatic organisms because of its higher sensitivity and simplicity.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권5호
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• pp.2122-2140
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• 2020

Proper and precise embedding of commercial ads within Webpages requires Ad-hoc analysis and understanding of their content. By the successful implementation of this step, both publishers and advertisers gain mutual benefits through increasing their revenues on the one hand, and improving user experience on the other. In this research work, we propose a novel multi-level context-based ads serving approach through which ads will be served at generic publisher websites based on their contextual relevance. In the proposed approach, knowledge encoded in domain-specific and generic semantic repositories is exploited in order to analyze and segment Webpages into sets of contextually-relevant segments. Semantically-enhanced indexes are also constructed to index ads based on their textual descriptions provided by advertisers. A modified cosine similarity matching algorithm is employed to embed each ad from the Ads repository into one or more contextually-relevant segments. In order to validate our proposal, we have implemented a prototype of an ad serving system with two datasets that consist of (11429 ads and 93 documents) and (11000 documents and 15 ads), respectively. To demonstrate the effectiveness of the proposed techniques, we experimentally tested the proposed method and compared the produced results against five baseline metrics that can be used in the context of ad serving systems. In addition, we compared the results produced by our system with other state-of-the-art models. Findings demonstrate that the accuracy of conventional ad matching techniques has improved by exploiting the proposed semantically-enhanced context-based ad serving model.

• 대한전자공학회논문지TE
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• 제42권1호
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• pp.35-40
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• 2005

최근 들어 이동 통신에서 이동하는 고객의 위치정보와 관련된 서비스가 중요하게 부각되고 있다. 이동 객체의 경우 갱신 연산이 많고 부하가 특정 지역에 집중되는 특징이 있다. 이러한 LBS 응용에서 시공간 영역질의는 중요한 부분이고, 질의 처리속도의 개선을 위해서 디스크 입출력 시간을 최대한 줄일 필요가 있다. 본 논문에서는 갱신연산을 최소화하기 위해 고안되어진 시공간 인덱스 구조로 비 균등 2단계 격자 인덱스 구조를 적용한다. 또한 질의 처리률 향상을 위해서 공간 관련성과 시간 관련성을 이용한 스케줄링 기법과 time zone 개념을 사용하여 시공간 개념이 결합된 질의 처리 기법을 제안한다. 다양한 질의 범위를 사용하여 실험한 결과 제안된 방법이 기존의 방법보다 우수함을 알 수 있었다.

• 대한지역사회영양학회지
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• 제11권4호
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• pp.534-540
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• 2006

Recent studies have shown that environmental, biochemical, nutritional or genetic factors affect bone mineral density (BMD). The purpose of the present study was to investigate the effect of vitamin D receptor (VDR) gentotype and nutritional status on BMD of elderly women living in a rural area. Three hundred thirty five elderly women over 65 years in Asan participated the study. Data for demographic and nutrient intakes were obtained by survey with a two day 24 hr recall method. BMD was measured by broadband ultrasound attenuation (BUA) using quantitative ultrasound (QUS). VDR genotypes of the subjects analyzed with Bsm I restriction enzyme were bb (92%), Bb (7%) and BB (1%). No differences were found between genotypes bb and Bb/BB in age, menopausal age, body mass index and body fat. BUA of bb genotype was higher (62.5 $\pm$ 15.6 dB/MHz) than Bb/BB genotype (56.1 $\pm$ 17.6 dB/MHz) by Student's t-tests. Correlation analyses showed strong negative correlation of BMD and age, but positive correlation with BMI, energy and calcium intake. When subgroup analyses were conducted after stratification by the median calcium intake level (412.9 mg/d), the above median calcium intake group showed significant difference in BUA by VDR genotype while the lower median calcium intake group did not show significant difference. The current study confirmed interaction of calcium intake and VDR genotype in association with BMD. Further nutritional intervention will be needed to improve calcium status of the elderly women living in rural areas.

• Smart Structures and Systems
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• 제21권5호
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• pp.705-713
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• 2018

High-speed rail (HSR) has been in operation and development in many countries worldwide. The explosive growth of HSR has posed great challenges for operation safety and ride comfort. Among various technological demands on high-speed trains, vibration is an inevitable problem caused by rail/wheel imperfections, vehicle dynamics, and aerodynamic instability. Ride comfort is a key factor in evaluating the operational performance of high-speed trains. In this study, online monitoring data have been acquired from an in-service high-speed train for condition assessment. The measured dynamic response signals at the floor level of a train cabin are processed by the Sperling operator, in which the ride comfort index sequence is used to identify the train's operation condition. In addition, a novel technique that incorporates salient features of Bayesian inference and time series analysis is proposed for outlier detection and change detection. The Bayesian forecasting approach enables the prediction of conditional probabilities. By integrating the Bayesian forecasting approach with time series analysis, one-step forecasting probability density functions (PDFs) can be obtained before proceeding to the next observation. The change detection is conducted by comparing the current model and the alternative model (whose mean value is shifted by a prescribed offset) to determine which one can well fit the actual observation. When the comparison results indicate that the alternative model performs better, then a potential change is detected. If the current observation is a potential outlier or change, Bayes factor and cumulative Bayes factor are derived for further identification. A significant change, if identified, implies that there is a great alteration in the train operation performance due to defects. In this study, two illustrative cases are provided to demonstrate the performance of the proposed method for condition assessment of high-speed trains.

• 한국측량학회지
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• 제34권4호
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• pp.431-441
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• 2016

Since the use of UAV (Unmanned Aerial Vehicle) is convenient for the acquisition of data on broad or inaccessible regions, it is nowadays used to establish spatial information for various fields, such as the environment, ecosystem, forest, or for military purposes. In this study, the process of estimating FVC (Fractional Vegetation Cover), based on multi-spectral UAV, to overcome the limitations of conventional methods is suggested. Hence, we propose that the FVC map is generated by using multi-spectral imaging. First, two types of result classifications were obtained based on RF (Random Forest) using RGB images and NDVI (Normalized Difference Vegetation Index) with RGB images. Then, the result map was reclassified into vegetation and non-vegetation. Finally, an FVC map-based RF were generated by using pixel calculation and FVC map-based GI (Gutman and Ignatov) model were indirectly made by fixed parameters. The method of adding NDVI shows a relatively higher accuracy compared to that of adding only RGB, and in particular, the GI model shows a lower RMSE (Root Mean Square Error) with 0.182 than RF. In this regard, the availability of the GI model which uses only the values of NDVI is higher than that of RF whose accuracy varies according to the results of classification. Our results showed that the GI mode ensures the quality of the FVC if the NDVI maintained at a uniform level. This can be easily achieved by using a UAV, which can provide vegetation data to improve the estimation of FVC.

• 한국환경복원기술학회지
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• 제19권3호
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• pp.29-44
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• 2016

The purpose of this study is to quantitatively and visually analyze the degree of green biotope fragmentation caused by road construction and other development work using FRAGSTATS and GUIDOS tool. Moreover, linking of the endangered species research, we mapped "Biotope Fragmentation Map" of Daejeon-city. The findings of the study are summarized as follows: First, as the result of FRAGSTATS, landscape indices : number of patch(NP), mean patch size (MPS), edge length(TE), mean nearest neighbor distance(MNN), edge shape(LSI) showed meaningful change from fragmentation. Moreover, the result of GUIDOS analysis, middle core-small core-bridge-branch-edge-islet-perforation showed increase of area percentage without large core. Lastly, analysis result of 'Biotope Fragmentation Map' revealed that changing site of large core's size appeared eighteen-site and designated as the special protection area appeared forty-one site. As the result of the two data, overlapping areas that showed both change of core size and revealed special protection areas revealed four site. For example, five species of endangered species appeared on the NO. 4 site in 'Biotope Fragmentation Map'. The findings of this study as summarized above are considered to play an important role in basic data preventing green biotope fragmentation at the planned level from various development work.

• Journal of Dental Anesthesia and Pain Medicine
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• 제21권1호
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• pp.61-69
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• 2021

Background: Inferior alveolar nerve block (IANB) using lidocaine 2% is commonly used for anesthetizing primary mandibular molars; however, this technique has the highest level of patient discomfort compared to other local anesthesia techniques. Therefore, alternative anesthesia techniques are necessary. The aim of this study was to evaluate the efficacy of a single buccal infiltration of 4% articaine with IANB using 2% lidocaine, for the bilateral extraction of primary mandibular molars. Methods: The present study was conducted on 30 patients aged between 6 and 9 years, who required the extraction of bilateral primary mandibular molars. The patients were randomly divided into two groups as follows: In the first session, Group A received IANB with lidocaine 2% and group B received infiltration with articaine 4%. In the second session, another injection method was performed on the opposite side. The Wong-Baker Facial Pain scale (WBFPS), Face Leg Activity Cry, and Consolability (FLACC), and physiologic parameters were used to assess pain perception. Results: The independent t-test showed no statistically significant difference in blood pressure and heart rate before and after extraction (P > 0.05). The mean FLACC index in the lidocaine and articaine groups was 0.89 and 1.36, respectively; there was no statistically significant difference between them (P > 0.05). According to the results of the chi-square test, there was no statistically significant difference between the groups for WBFPS (P > 0.05). Conclusion: The articaine infiltration technique may be an alternative to the IANB for the extraction of primary mandibular molars.