• Computers and Concrete
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• 제23권2호
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• pp.133-143
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• 2019

The paper presents the experimental investigations into the effect of ground granulated blast furnace slag (GGBFS) on the time-dependent tensile strength of concrete. The splitting and flexural tensile strength of concrete was determined at the ages of 3, 7, 28, 56, 90, 150 and 180 days using the cylindrical and prism specimens respectively for plain and GGBFS concrete. The amount of cement replacement by GGBFS was 0%, 40% and 60% on the weight basis. The maximum curing age was kept as 28 days. The results showed that the splitting and flexural tensile strength of concrete containing GGBFS has been found lower than the plain concrete at all ages and for all mixes. The tensile strength of 40 percent replacement has been found higher than the 60 percent at all ages and for all mixes. The rate of gain of splitting and flexural tensile strength of 40 percent GGBFS concrete is found higher than the plain concrete and 60 percent GGBFS concrete at the ages varying from 28 to 180 days. The experimental results of time-dependent tensile strength of concrete are compared with the available models. New models for the prediction of time-dependent splitting and flexural tensile strength of concrete containing GGBFS are proposed. The present experimental and analytical study will be helpful for the designers to know the time-dependent tensile properties of GGBFS concrete to meet the design requirements of liquid retaining reinforced and pre-stressed concrete structures.

• 한국지형학회지
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• 제27권1호
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• pp.47-60
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• 2020

This study tried to produce an uplift rate map and reveal the spatial distribution of the rate with topographical characteristics and absolute ages on marine terrace in the East Coast of the Korean Peninsula. Based on a total of 57 ages at 26 sites from previous study and 13 ages at 13 sites from this study, the coast showed the rates ranging from 0.145 m/ka to 0.410m/ka with an average of 0.258 m/ka. The highest and lowest rates were found from the Jeongdongjin area in Gangneung and the Goraebul area in Yeongdeok, respectively. However, some areas in the coast showed large differences in the rate among the sites. In addition, areas with only 1 age were also found, indicative of low reliability. This study suggests that a more reliable and precise interpretation on the rate can be made with more ages identified, especially in Goseong to northern part of Gangneung, middle and southern parts of Samcheok and Yeongdeok, southern part of Pohang to northern part of Gyeongju, and Ulsan.

• Journal of Microbiology and Biotechnology
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• 제34권3호
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• pp.580-588
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• 2024

Microbial communities in mangrove forests have recently been intensively investigated to explain the ecosystem function of mangroves. In this study, the soil microbial communities under young (<11 years-old) and old (>17 years-old) mangroves have been studied during dry and wet seasons. In addition, biogeochemical properties of sediments and methane emission from the two different mangrove ages were measured. The results showed that young and old mangrove soil microbial communities were significantly different on both seasons. Seasons seem to affect microbial communities more than the mangrove age does. Proteobacteria and Chloroflexi were two top abundant phyla showing >15%. Physio-chemical properties of sediment samples showed no significant difference between mangrove ages, seasons, nor depth levels, except for TOC showing significant difference between the two seasons. The methane emission rates from the mangroves varied depending on seasons and ages of the mangrove. However, this did not show significant correlation with the microbial community shifts, suggesting that abundance of methanogens was not the driving factor for mangrove soil microbial communities.

• 가정과삶의질연구
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• 제27권3호
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• pp.159-170
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• 2009

The purpose of this study was (1) to investigate the difference of temperament, self-regulation, and problem behavior according to children's gender and age, (2) to investigate the relationship among three variables by use of canonical correlation analysis. The subjects were 210 children ages from 3 to 5 in five day-care center in Incheon city. The SPSS WIN 12.0 Program was used to analyze the collected data. The statistical methods were Frequency, Percentage, Cronbach's ${\alpha}$, Two-way ANOVA, Correlation analysis, and Canonical Correlation analysis. The major results of this research are summarized as follows: (1) Children's temperament were significantly different by their gender and age. The boys got higher score than girls in adaptability, activity, and total temperament. Girls got higher score than boys in reactivity. The age 3 got higher score than the age 5 in activity and the ages 3, 4 got higher than the age 5 in total temperament. (2) Children's self-regulation were significantly different by their age. The children who were older got higher scores in self-regulation ability. (3) Children's problems behavior were significantly different by their gender and age. The boys got higher score than girls in anxiety behavior, aggressive behavior, hyperactive/distractive behavior, and total problem behavior. And the ages 3, 4 got higher score than the age 5 in anxiety behavior and hyperactive/distractive behavior. The age 4 got higher score the ages 3, 5 in aggressive behavior and the age 3 got higher score the ages 4, 5 in total problem behavior. (4) Canonical correlation results showed that stable temperament and self-regulation were positively correlated and self-regulation and problem behavior were negatively correlated.

• 동의생리병리학회지
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• 제26권2호
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• pp.147-154
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• 2012

Hwanggeum-tang (HGT) was recorded in Dongeuibogam as being able to treat Sogal whose concept had been applied to Diabetes Mellitus (DM). Advanced glycation end products (AGEs) play important roles in the development of diabetic complications such as atherosclerosis by eliciting inflammatory responses. In this study, we examined the suppressive effects of HGT against inflammation elicited by AGEs. AGEs treatment increased the expression of pro-inflammatory cytokine gene TNF-${\alpha}$; chemokines MCP-1, IP-10; pro-inflammatory cyclooxygenase COX-2 on the THP-1 cells. HGT had suppressed the expression of pro-inflammatory genes and protein levels in AGE-treated THP-1 cells. HGT had also decreased intracellular ROS production stimulated by AGEs. These results suggest that HGT has beneficial effects for the improvement diabetic vascular complication through suppressing inflammatory responses elicited by AGEs.

• 자원환경지질
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• 제23권2호
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• pp.135-141
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• 1990

A number of alunite and pyrophyllite deposits occur around the Haenam area where Cretaceous volcanic and volcanogenic sediments are widely distributed. The K-Ar ages of alunite, sericite and whole rocks collected from alunite and pyrophyllite deposits and unaltered rocks representing various stratigraphic horizon of the area were determined and their formation stage was discussed. The ages of volcanic rocks range between $68.6{\pm}1.9$ and $94.1{\pm}2.0$ Ma corresponding to Cenomanian-Maastrichtian of upper Cretaceous. Andesitic rock gives $94.1{\pm}2.0$. Rhyolite and acidic tuffs give $79.47{\pm}1.7$ and $82.8{\pm}1.2$ Ma corresponding to Campanian. The later stage andesite gives $68.6{\pm}1.9$ Ma of Maastrichtian. The results suggest that volcanism of the area can be devided into three different stages. The ages of alunite and sericite range $71.8{\pm}2.8$ to $76.6{\pm}2.9$ Ma of late Campanian to early Maastrichtian which is rather earlier than the age of granite(67 Ma). It indicates that the alteration ages of these clay mineral deposits appeared to be related with its volcanism rather than the hydrothermal stage of granite of this area.

• 대한장애인치과학회지
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• 제8권1호
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• pp.1-9
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• 2012

Mobile oral exam at the facilities for the disabled in Seoul is to improve the oral health of the disabled who can hardly approach dental clinic. We analyzed 1609 oral exam records at 24 facilities (11 special-education schools, 10 living facilities, 2 mental hospitals, 1 health care facility for the elderly) in 2011. The purpose of this study is to figure out the oral health state of the disabled in facilities in Seoul and to compare with the non-disabled in National Survey 2010 and 2008. 1. Special-education school : DMFT index of age 15 is 5.4 which is higher than 3.6 (DMFT index of age 15) of National Survey in 2010. 2. Living facility : DMFT index of ages 35~44 is 8.4 which is higher than 5.2 (DMFT index of ages 35 ~44) of National Survey in 2008. DT rate is higher (31.3% vs 19.2%) and MT rate is lower (7.6% vs 15.5%). 3. Mental hospital : DMFT index of ages 35~44 is 11.3 which is higher than 5.2 (DMFT indext of age 35~44) of National Survey in 2008. DT rate is significantly higher (50.7% vs 19.2%) and FT rate is lower (35.1% vs 65.3%). 4. Health care facility for the elderly : DMFT index of ages 65~74 is 7.1 which is slightly lower than 8.7 (DMFT index of ages 65~74) of National Survey in 2008. The number of existing natural teeth is similar (16 vs 18).

• 대한한방내과학회지
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• 제35권4호
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• pp.519-531
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• 2014

Objectives: Diabetic nephropathy is the most common cause of end stage renal disease. Transforming growth factor (TGF)-${\beta}1$, type IV collagen, advanced glycation end-products (AGEs), and angiotensin II type 1 receptor (AT1) are the main factors of diabetic nephropathy. We investigated the effects of Prunus on renal function and histopathological changes of diabetic nephropathy rat model induced by unilateral nephrectomy and streptozotocin. Methods: Diabetes was induced in male Sprague-Dawley rats ($290{\pm}10g$) by injecting streptozotocin (55 mg/kg) into the tail vein after unilateral nephrectomy. Rats were divided into 3 groups (n=6): normal, control, and Prunus. After 8 weeks of oral administration of Prunus extract on the Prunus group from 3 days after streptozotocin injection, we checked weight, 24 hrs urine, blood biochemistry and renal tissue to evaluate renal function and histopathological changes by examining parameters including albuminuria, BUN, creatinine, cholesterol, low density lipoprotein (LDL), triglyceride, TGF-${\beta}1$, type IV collagen, AGEs, and AT1. We also measured mRNA expression of TGF-${\beta}1$, type IV collagen, AGEs, and AT1 by Real Time polymerase chain reaction (RT-PCR). Results: Prunus decreased the amount of 24 hrs proteinuria, and inhibited histopathological changes of diabetic nephropathy including the expression and accumulation of TGF-${\beta}1$, type IV collagen and AGEs which could promote development of diabetic nephropathy. Prunus also inhibited mRNA expression of TGF-${\beta}1$, type IV collagen. Conclusions: These findings suggest that Prunus might protect the renal function and inhibit the development of renal injury by regulating factors including TGF-${\beta}1$, type IV collagen, AGEs, except AT1, so Prunus can be used for diabetic patients to prevent the progression of diabetic nephropathy.

• 한국실내디자인학회논문집
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• 제25권1호
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• pp.56-64
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• 2016

Housing for the elderly should be planned on the base of elder's needs and preferences as well as their physical, emotional, and socio-psychological characteristics. This study examined the interior style of bedroom and living room the elderly preferred and these preferences are significantly different depending on their characteristics and cognitive ages, or not. This study was carried out by face to face interview with a questionnaire and 6 colored printed 3D images. The subjects were 202 old aged who lives in Busan. The interior style of bedroom and living room were classified into 3 styles; Korean traditional style, Western classical style, and modern style. The subjects made a choice their preferred interior style among three 3D images per each room and answered the reasons. Also, they answered their cognitive ages and general characteristics, and their preferences for the layout of living room-dining room-kitchen, use pattern, floor finishes, and furniture of bedroom and living room. The results were as follows; 1) The subjects preferred bed in bedroom and sofa in living room. Also, they wanted to finish the floor of bedroom and living room by using synthetic material, traditional floor paper, and wood. 2) The elderly preferred Western classical style of bedroom. The reasons were general mood such as warm, comfort, or bright, and the color. 3) These preferred styles were not any significant differences according to their characteristics and cognitive ages. 4) They preferred Korean traditional style, Western classical style, and modern style, in order. They preferred them for their general mood and window. 5) Their preferred styles were significantly different according to their housing types and cognitive ages.

• 한국의상디자인학회지
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• 제11권2호
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• pp.117-129
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• 2009

This study is to examine unmarried women's preferences about wedding dresses. This is researched with a survey of 300 unmarried women in Ulsan and Seoul. The survey inquires their preferences of silhouettes, necklines, materials, and details in wedding dress. 290 valid questionnaires are analyzed statistically. Statistical analysis is used average, frequency, and crosstabs with SPSS10.0. The results of this study are as below; As for an income level, the high-income brackets in Ulsan preferred X silhouette, whereas in Seoul H silhouette. The low-income brackets in both areas preferred X silhouette. In necklines, boat neckline was preferred in both areas regardless of incomes. In materials, in Ulsan, the high-income brackets preferred silk, but the low-income brackets in Ulsan preferred satin. In Seoul, silk was preferred regardless of incomes. In details, the high-income brackets in both areas preferred beads and ribbon. In the low-income brackets, embroidery decorations were preferred in Ulsan, whereas beads, jewels and ribbons in Seoul. As for personalities, X silhouette was preferred in most personalities, A silhouette in some personalities in Seoul. In necklines, boat neckline is preferred in most personalities. In materials, silk was preferred in most personalities. In details, beads and jewels were preferred in most personalities. As for ages, in most ages, X silhouette was preferred in Ulsan, and X and A silhouettes in Seoul. In necklines, in most ages, boat neckline was preferred in both areas. In materials, silk was preferred in most ages. In details, beads and jewels were preferred in most ages.