• 통합자연과학논문집
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• 제14권1호
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• pp.6-10
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• 2021

New materials are very useful due to their wide range of applications, however, they also have caused new pollutants that damage our environment. Chemists have been conscious of the severity of these environmental problems and a great deal of effort has been put into developing environmentally benign chemical processes to synthesize new materials (green synthesis). We also have reported a green synthesis method of synthesizing silver nanoparticles using water-glycerol solution in a previous study. While conducting further research, we have recently discovered that the size of silver nanoparticles is proportional to the quantity of water present in glycerol. This method is completely benign and ecofriendly pathway, as the size of silver nanoparticles is adjusted solely by controlling the quantity of water added to glycerol, without extra additives and energy.

• Journal of Information Processing Systems
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• 제17권2호
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• pp.426-439
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• 2021

To alleviate the cold-start problem and data sparsity in web service recommendation and meet the personalized needs of users, this paper proposes a personalized web service recommendation method based on a hybrid social network and multi-objective immune optimization. The network adds the element of the service provider, which can provide more real information and help alleviate the cold-start problem. Then, according to the proposed service recommendation framework, multi-objective immune optimization is used to fuse multiple attributes and provide personalized web services for users without adjusting any weight coefficients. Experiments were conducted on real data sets, and the results show that the proposed method has high accuracy and a low recall rate, which is helpful to improving personalized recommendation.

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1413-1418
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• 2012

Background: Previous studies generally indicate that synchronous bilateral breast cancers (SBBC) have an equivalent or moderately poorer survival compared with unilateral cases. The prognostic characteristics of SBBC would be relevant when planning adjuvant therapies and follow-up medical surveillance. The frequency of SBBC among early breast cancers in clinical settings in Australia and New Zealand was investigated, plus their prognostic significance, using the Breast Cancer Audit Database of the Society of Breast Surgeons of Australia and New Zealand, which covered an estimated 60% of early invasive lesions in those countries. Design: Rate ratios (95% confidence limits) of SBBC were investigated among 35,370 female breast cancer cases by age of woman, histology type, grade, tumour diameter, nodal status, lymphatic/vascular invasion and oestrogen receptor status. Univariate and multivariable disease-specific survival analyses were undertaken. Results: 2.3% of cases were found to be SBBC (i.e., diagnoses occurring within 3 months). The figure increased from 1.4% in women less than 40 years to 4.1% in those aged 80 years or more. Disease-specific survivals did not vary by SBBC status (p=0.206). After adjusting for age, histology type, diameter, grade, nodal status, lymphatic/vascular invasion, and oestrogen receptor status, the relative risk of breast cancer death for SBBC was 1.17 (95% CL: 0.91, 1.51). After adjusting for favourable prognostic factors more common in SBBC cases (i.e., histology type, grade, lymphatic/vascular invasion, and oestrogen receptor status), the relative risk of breast cancer death for SBBC was 1.42 (95% CL: 1.10, 1.82). After adjusting for unfavourable prognostic factors more common in SBBC cases (i.e., older age and large tumour diameter), the relative risk of breast cancer death for SBBC was 0.98 (95% CL: 0.76, 1.26). Conclusions: Results confirm previous findings of an equivalent or moderately poorer survival for SBBC but indicate that SBBC status is likely to be an important prognostic indicator for some cases.

• Wind and Structures
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• 제30권3호
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• pp.317-323
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• 2020

A novel approach is presented to improve dynamic responses of a pedestrian bridge by utilizing decorative wind chimes. Through wind tunnel tests, it was verified that wind chimes can provide stabilization effects against flutter instability, especially at positive or negative wind angles of attack. At zero degrees of angle of attack, the wind chimes can change the flutter pattern from rapid divergence to gradual divergence. The decorative wind chimes can also provide damping effects to suppress the lateral sway motion of the bridge caused by pedestrian footfalls and wind forces. For this purpose, the swing frequency of the wind chimes should be about the same as the structural frequency, which can be achieved by adjusting the swing length of the wind chimes. The mass and the swing damping level are other two important and mutually interactive parameters in addition to the swing length. In general, 3% to 5% swing damping is necessary to achieve favorite results. In the study case, the equivalent damping level of the entire system can be increased from originally assumed 1% up to 5% by using optimized wind chimes.

• Asian Journal of Atmospheric Environment
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• 제7권1호
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• pp.56-63
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• 2013

Children are particularly vulnerable to adverse health effects associated with heavy metal exposure. The goal of this study was to investigate the relationship between proximity to an industry complex and blood lead and urinary cadmium levels for children aged 7-13 who lived in Ulsan where a big petrochemical complex is located. We conducted a questionnaire survey to collect data including sociodemographics, daily habits, residential environment, etc. We also analyzed blood lead and urinary cadmium levels using Atomic Absorption Spectrometry (AAS). Data were analyzed using regression analysis. All statistical analyses were conducted with SAS software version 9.2. We calculated distance by using a Geographic Information System (ArcGIS version 10.0). The geometric mean blood lead level was 1.55 ${\mu}g/dL$ (boys: 1.59 ${\mu}g/dL$, girls: 1.51 ${\mu}g/dL$), and the geometric mean urinary cadmium level was 0.51 ${\mu}g/g$ creatinine (boys: 0.45 ${\mu}g/g$ creatinine, girls: 0.58 ${\mu}g/g$ creatinine). In the results of regression analyses, we found that urinary cadmium levels significantly decreased as distance between residence and industrial complex increased after adjusting for age, gender, income, passive smoking and the length of residence. This result was opposite to that for lead levels. Our observations support the hypothesis that urinary cadmium levels in children are related to their proximity to an industrial complex.

• 대한간호학회지
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• 제38권2호
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• pp.195-203
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• 2008

Purpose: The purpose of this study was to understand the level of functional health literacy and its influence on perceived health status in Korean older adults. Methods: A cross-sectional survey was conducted in Daegu, Kyungpook and Susan province. A total of 103 older adults aged 65 yr or older were interviewed in person between July 1 to August 30, 2007. Results: A high proportion of older adults were unable to read and understand written basic medical instructions. Only 40-50% were able to comprehend directions for taking medication four times a day or on an empty stomach. Only 11-38% were able to understand information regarding treatment procedure, informed consent, or educational material for elderly fall prevention. Individuals who were older, single, and had less education and income were more likely to have lower functional health literacy. After adjusting for sociodemographic variables, individuals with lower health literacy had poorly perceived health status. Conclusion: Many Korean older adults have a very low level of fuctional literacy. Low health literacy was independently associated with poorly perceived health status.

• 한국멀티미디어학회논문지
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• 제6권4호
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• pp.576-582
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• 2003

Because of today's rapid growth of digital contents market and many benefits of electronic book, many people have considerable interest in E-book. Furthermore multifarious consortiums take an active part in standardization of I-book, and many E-book tools have been provided by software manufactures all over the world. E-book tools include editor for production of E-Book, viewer for reading, and the like. Especially in E-book viewer, annotation function has to be Included to put arrangement, summation, recording, comment, emphasis and after comprehension to practical use. In this paper, a E-book viewer with annotation is designed according to the specifications of EBKS, Korean standard. The proposed viewer is aimed to implement in PDA with embedded Linux, but developed in Windows 2000 platform. Because development environment and application environment are different each other, Qt-Library and cross-compiler are used for cross-platform development. The viewer support various functions such as adjusting of font size, hypertext linking, retrieval of specific word, and so forth. And in addition to these basic functions, annotation function is designed for the viewer, which can be used for re-usage and sharing of important information.

• 한국농촌간호학회지
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• 제8권1호
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• pp.33-41
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• 2013

Purpose: The study was done to explore relationships between residential areas and smoking rates and to identify related factors contributing to smoking in Korea adolescents. Methods: An analysis was done of smoking rates and socioeconomic position indicators by city size based on a 2012 cross-sectional nationwide online survey conducted with 74,186 Korean middle and high school students aged 12-18 years old. Data were analyzed using x2-test and multiple logistic regression with the SPSS/WIN18.0 program. Results: Analyses revealed that rural boys were more likely to be current smokers compared to metropolitan boys (odds ratio 1.18, 95%-confidence interval 1.01; 1.38) but residential areas and smoking rates among girls were not related. After adjusting for covariates, results showed that city size, Family affluence score, economic status, parents' education level, living with parents, school type, and school achievement were related to increased an proportion of adolescents who smoked. Conclusion: In conclusion, rural living is a determinant of smoking among boys. Tobacco control programs should recognize differences in living conditions between rural and urban areas.

• Structural Engineering and Mechanics
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• 제25권6호
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• pp.717-732
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• 2007

A formula to approximate the fundamental period of a fixed-free mass-spring system with varying mass and varying stiffness is formulated. The formula is derived mainly by taking the dominant parts from the general form of the characteristic polynomial, and adjusting the initial approximation by a coefficient derived from the exact solution of a uniform case. The formula is tested for a large number of randomly generated structures, and the results show that the approximated fundamental periods are within the error range of 4% with 90% of confidence. Also, the error is shown to be normally distributed with zero mean, and the width of the distribution (as measured by the standard deviation) tends to decrease as the total number of discretized elements in the system increases. Other possible extensions of the formula are discussed, including an extension to a continuous cantilever structure with distributed mass and stiffness. The suggested formula provides an efficient way to estimate the fundamental period of building structures and other systems that can be modeled as mass-spring systems.

• Journal of Preventive Medicine and Public Health
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• 제45권2호
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• pp.98-104
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• 2012

Objectives: A positive association between serum albumin levels and metabolic syndrome has been reported in observation studies, but it has not been established in the Korean population. The purpose of this study was to evaluate the association between serum albumin levels and the presence of metabolic syndrome among a sample of apparently healthy Korean adults. Methods: This cross-sectional study analyzed data of 3189 community-dwelling people (1189 men and 2000 women) who were aged 40 to 87 years and were living in a rural area in Korea. Serum albumin levels were classified into quartile groups for each sex. Metabolic syndrome was defined according to the National Cholesterol Education Program Adult Treatment Panel III guidelines with an adjusted waist circumference cut-off value ${\geq}90\;cm$ for men and${\geq}85\;cm$ for women). An independent association between serum albumin levels and metabolic syndrome was assessed by multiple logistic regression analysis. Results: Higher serum albumin levels were associated with increased prevalence of metabolic syndrome. The odds ratio (95% confidence interval) of the prevalence of metabolic syndrome for the highest versus the lowest serum albumin quartiles was 2.81 (1.91 to 4.14) in men and 1.96 (1.52 to 2.52) in women, after adjusting for age, smoking status, alcohol consumption, and physical activity. When each metabolic abnormality was analyzed separately, higher serum albumin levels were significantly associated with hypertriglyceridemia and hyperglycemia in both sexes, and with abdominal obesity in men. Conclusions: These results suggest that higher serum albumin levels are positively associated with an increased risk of metabolic syndrome in Korean adults.