• Smart Structures and Systems
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• 제20권2호
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• pp.197-205
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• 2017

The dynamic performance of railway bridges under high-speed trains draws the attention of bridge engineers. The vibration issue for long-span bridges under high-speed trains is still not well understood due to lack of validations through structural health monitoring (SHM) data. This paper investigates the correlation between bridge acceleration and train speed based on structural dynamics theory and SHM system from three foci. Firstly, the calculated formula of acceleration response under a series of moving load is deduced for the situation that train length is near the length of the bridge span, the correlation between train speed and acceleration amplitude is analyzed. Secondly, the correlation scatterplots of the speed-acceleration is presented and discussed based on the transverse and vertical acceleration response data of Dashengguan Yangtze River Bridge SHM system. Thirdly, the warning indexes of the bridge performance for correlation scatterplots of speed-acceleration are established. The main conclusions are: (1) The resonance between trains and the bridge is unlikely to happen for long-span bridge, but a multimodal correlation curve between train speed and acceleration amplitude exists after the resonance speed; (2) Based on SHM data, multimodal correlation scatterplots of speed-acceleration exist and they have similar trends with the calculated formula; (3) An envelope line of polylines can be used as early warning indicators of the changes of bridge performance due to the changes of slope of envelope line and peak speed of amplitude. This work also gives several suggestions which lay a foundation for the better design, maintenance and long-term monitoring of a long-span high-speed bridge.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2008년도 춘계 학술논문 발표대회
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• pp.57-60
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• 2008

This study investigated the results of insulation heat curing method using double layer bubble sheet in slab concrete and mass concrete in cold weather environment. First of all, when double bubble sheets are applied, it was shown that slab concrete was protected from early freezing by remaining between 6 and 15℃ even in case outside temperature drops -9℃ below zero until the 2nd day from piling, and in the case of mass concrete, with the maximum temperature difference between the center and surface less than 4℃, crack occurrence index was close to 2 and no hydration heat crack occurred by internal constraint. The insulation heat preservation curing method using the double bubble sheet applied in this field prevented early freezing owing to stable curing temperature management, deterring concrete strength development delay at low temperature, and obtained the needed strength. Also, it was proven that the method is highly effective and economic for cold weather concrete quality maintenance through curing cost reduction like construction period shortening and labor cost reduction, etc by reducing the process of temporary equipment installation and disassembling.

• 한국식생활문화학회지
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• 제33권1호
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• pp.62-69
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• 2018

The purpose of this study was to investigate the antioxidative and physical properties of finger food type rice snacks and pumpkin rice snacks for infants aged 6 to 12 months old. The addition of rice germ did not affect density or porosity, and there was no significant difference when compared with commercial products. The addition of rice germ to the rice snack group did not reduce the longitudinal expansion quality of the rice snack. The WAI of RW and SW values were 9.83 and 8.93, respectively, which were significantly higher than those of other samples (p<0.05). The results of this study show that the addition of rice germ to rice snack resulted in reduced density and porosity of rice snacks and maintenance of a high water absorption index, which are more desirable characteristics for products. The products with rice germ showed significantly higher antioxidative activities among all samples (p<0.05).

• The Journal of Korean Physical Therapy
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• 제23권3호
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• pp.43-47
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• 2011

Purpose: This study determined the best adjustable height supporter for stroke patients in wheelchairs for the maintenance of a symmetric sitting posture. Methods: Thirty-one stroke participants and 20 age-matched control participants were recruited. The enrolled participants were evaluated by the Force Sensitive Application (FSA) System that was used to assess weight shift and symmetry in wheelchair sitting and assess the symmetric index (SI) of subjects according to 1, 2 and 3 cm height supporters. Results: When a 1 cm height supporter was applied to the paretic side of stroke survivors, sitting postures of stroke patients were significantly more symmetrical (p<0.01). Cross tabulation between the SI of wheelchair sitting and that of the paretic side of stroke patients caused? by a 1 cm supporter showed that 21 SIs of 26 stroke patients were improved by a 1 cm supporter to the paretic side (k=0.26, p<0.01). Conclusion: The findings of the present study demonstrate that stroke patients can maintain a more symmetrical sitting posture (than is possible when simply sitting in a wheelchair seat) if a 1 cm supporter is applied to the paretic side of stroke patients.

• 동아시아식생활학회지
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• 제22권4호
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• pp.463-472
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• 2012

This study was performed to investigate the iron status and its related factors in female college students residing in Gyeongnam. The prevalence of iron deficiency among subjects ranged from 3.4% in mean corpuscular hemoglobin concentration (MCHC) to 43.7% in ferritin. Weight, lean body mass (LBM) and body mass index (BMI) were positively correlated with ferritin concentration, but negatively correlated with total iron binding capacity (TIBC). Among the nutrients, vitamin A and B2 were major predictors of elevated iron status. Meal regularity was positively correlated with Fe and ferritin concentration, and meal number with transferrin saturation (TS), meal quantity with red blood cell (RBC) and hematocrit (Hct). Consumption of fruit, meat, fish and poultry showed strong positive correlation with hematological indices. Therefore, increasing vitamin A, B2, C, and iron intakes as well as maintenance of a healthy weight may be helpful in preventing iron deficiency in female college students.

• 설비공학논문집
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• 제15권10호
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• pp.870-878
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• 2003

The maintenance of thermal equilibrium between the human body and its environment is one of the primary requirements for health, wellbeing and comfort. For the effective control of indoor thermal environment, thermostat or humidistat is used. But, it is not sufficient to control the indoor thermal environment using only one or two parameters as human response for the indoor comfortable environment. So an environmental thermal index is required for the control of indoor thermal environment effectively. In this study, a PMV sensor has been developed which has integrated from various kinds of individual sensors for temperature, humidity, air velocity, radiant temperature. After applying the PMV and PPD equation, it is possible to monitor the indoor thermal environment with the sensor system, which is adopted to the circuit for optimization according to the human response with the metabolic rate and activities. The measurement was carried out to verify the performance of the integrated sensor system in comparison with existing measurement system, the PMV meter. As a result, the possibility of applying the PMV sensor to control the indoor thermal environment simultaneously was examined.

• 임상간호연구
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• 제18권2호
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• pp.307-316
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• 2012

Purpose: The purpose of this study was to develop and test psychometric properties the Korean version of the End-Stage Renal Disease Adherence Questionnaire (KESRD-AQ). The ESRD-AQ, a 46-item, multidimensional, self-administrated questionnaire which was developed to assess treatment adherence to hemodialysis (HD) attendance, medications, fluid restrictions, and diet prescription among patients on maintenance hemodialysis, has been validated. Methods: The KESRD-AQ was developed by performing both translation and backtranslation. The content validity and test- retest reliability of the KESRD-AQ were evaluated by establishing item-level content validity index (I-CVI) and intra-class correlation coefficients (ICC), respectively. Construct validity was assessed by adopting a known-group analysis comparing adheres and non-adherers using Mann-Whitney U Test. Results: 41 Korean-American patients with ESRD on HD from 3 outpatient dialysis centers in California participated in the study. The KESRD-AQ showed excellent content validity (average I-CVI=.96) and test-retest reliability (ICC=.917, p=.004). The construct validity indicated that the KESRD-AQ distinguished adheres and non-adheres (p=.02~.047). Conclusion: The KESRD-AQ is a valid and reliable instrument to measure treatment adherence.

• 대한의생명과학회지
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• 제18권1호
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• pp.42-48
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• 2012

This study was performed to investigate the urinary methyl hippuric acid (UMHA) excretion among aircraft maintenance workers exposed to xylene by examination of blood test, urine test and biochemical tests. Study subjects (301) were divided into 2 groups; non-exposed group (n=123, who were not exposed to xylene), and exposed group (n=178, who were exposed to xylene). The average of blood level and MHA level was normal. The ${\gamma}$-GTP level was 35.5 IU/L (45.7%) in the exposed group and 27.9 IU/L (44.7%) in the non-exposed (control) group. The proportion of total cholesterol (TG) level higher than 150 mg/dl were 34.3% in the exposed group and 21.1% in the non-exposed group. These results were showed statistically significant difference (${\chi}^2$ = 6.10, P<0.05). Other items showed no statistically significant differences. The results of urine tests were no statistically significant differences in protein, occult blood and glucose level.

• 한국보건간호학회지
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• 제24권2호
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• pp.311-322
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• 2010

Purpose: This study aimed to examine the compliance to a low-salt diet, sodium intake, and preferred salty taste in elderly patients with hypertension. Methods: A cross-sectional descriptive design was used. Participants were 105 elderly patients with hypertension living in a rural area. The compliance with a low-salt diet, sodium intake, and preferred salty taste, blood pressure, body mass index, and waist circumference were measured, and compared according to the general characteristics and the levels of blood pressure. Descriptive statistics, $X^2$-test, t-test, and ANOVA were used for data analysis. Results: compliance with a low-salt diet was marginally elevated. Sodium intake was relatively high and the main sources were seasonings and vegetables. The participants tended to prefer high levels of salt. Sodium intake was significantly higher the hypertensive individuals (stage I and II) compared to prehypertensive subjects on a normal maintenance diet. Sodium intake from vegetables was also significantly different between the two groups. Conclusion: Nursing intervention for hypertensive elderly patients should include strategies to decrease sodium intake.

• The Korean Journal of Ecology
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• 제21권5_3호
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• pp.665-673
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• 1998

This study was conducted to clarified the relationship between bird community and forest structure and present the counterplan for protection and management of bird community from February 1993 to July 1995 at deciduous and coniferous forest within Mt. Nam area, Seoul, Korea. DBH distribution has not significant differences in each study site. Deciduous forest had more foliage coverage in all layers than coniferous forest. Total 41 species of birds, which were 16 species of resident, 14 species of summer visitor, 4 species of winter visitor, and 7 species of passage migrant were recrded in two study sites. Leaf use rate of birds was increased the increase of coverage. The number of breeding species and pairs, breeding density, and diversity index were greater in deciduous forest than coniferous forest. The number of species and pairs on bush-nesting and foraging guild were greater than other guilds. And the nuber of species and pairs on hole nesting guild were the fewest in nesting guild. Use rate of artificial nests for improvement of habitat quality was greater in coniferous forest than deciduous forest. Maintenance of bush layer, increase of coverage and leaf layer diversity, supply of artificial nests, management of large trees, and control of natural enemy were necessary for protection and management of bird community in Mt. nam area.