• 한국치위생학회지
• /
• 제18권6호
• /
• pp.903-910
• /
• 2018

Objectives: The study aimed to identify the oral health factors that affect the nutritional status of the elderly. Methods: The study was conducted over ten months from September 2013 to June 2014, and included senior citizens who were supported by the visiting health service. The rate of saliva release, the number of remaining teeth, and the ability of the elderly to identify nutritional conditions were evaluated. Statistical analyses were performed using the t-test, ANOVA, and multiple linear regression using SAS 9.4 (SAS Institute Inc., Cary, NC, USA.). Results: The study participants had an average irritation saliva secretion rate of $2.26{\pm}1.11mg$ per minute. The higher the rate of saliva secretion, the higher the mini nutritional assessment (MNA) score (p<0.001). The average number of remaining teeth was $8.21{\pm}9.76$. The MNA scores were highest in groups with 11 or more remaining teeth (p=0.001). The factors that affected the nutritional condition of the elderly were their ability to perform activities of daily living, saliva flow rate, and number of remaining teeth. The highest correlation among them was that of the standardized regression coefficient was - 0.386 by activity daily living, followed by a 0.170 saliva secretion rate and 0.118 remaining teeth in daily life performance. Conclusions: Activities of daily living and rate of saliva secretion showed the highest correlations to nutritional status of the elderly.

• 대한치과의사협회지
• /
• 제58권1호
• /
• pp.38-44
• /
• 2019

Although the Korea National Health and Nutrition Examination Survey (KNHANES) calculates oral health functional restriction rate and chewing discomfort rate every year, these two indicators are not all indicators of oral health. Therefore, indicators are needed to subdivide by age group and cover dental caries, periodontal disease, remaining teeth, and oral care use. The purpose of this study is to identify the key indicators of oral health in mature and middle age. The average number of existing natural teeth, the rates of 20 or more natural teeth, complaints of chewing discomfort, oral examination, periodontal disease and dental caries, were analyzed using KNHANES VI (2013-2015) as a complex sample. In the age group between 40 and 64, there were 25.2 natural teeth remaining, 91.4% natural teeth retention rate, 23% chewing discomfort rate, 34.7% oral examination rate, 38.7% periodontal disease prevalence, 6.46 the number of caries experience teeth, 21.4% interdental brush usage rate.

• The Korean Journal of Ecology
• /
• 제27권2호
• /
• pp.93-98
• /
• 2004

상수리나무 가지의 분해율과 분해과정에 따른 영양염류의 변화를 33개월 동안 조사하였다. 33개월 경과 후 가지 의 잔존률은 B₁(직경＜1㎝), B₂(1㎝≤직경＜2㎝), B₃(3㎝≤직경＜4㎝)가 각각 44.5%, 58.5%, 55.3% 이었다. B₁, B₂, B₃의 분해 상수는 각각 0.294/yr, 0.195 /yr, 0.215/yr 이었다. 분해 과정에 따른 질소 함량은 모든 직경급에서 증가하는 경향을 보였다. 33개월 경과 후 질소 잔존률은 B₁, B₂, B₃가 각각 101.2%, 91.9%, 104.4% 이었다. 인 함량은 B₁과 B₂에서 분해가 진행됨에 따라 초기 함량보다 증가하였고, 분해 과정중 인의 부동화 기간은 없었으며, 33개월 경과 후 인 잔존률은 B₁, B₂, B₃가 각각 57.2%, 74.4%, 53.9%이었다. 칼륨 함량은 분해가 진행됨에 따라 초기 값보다 현저하게 감소하였으며, 33 개월 경과 후 잔존률은 B₁, B₂, B₃가 각각 7.7%, 17.1%, 17.2%로 다른 영양염류에 비해 낮았다. 칼슘 함량은 B₁을 제외하고 분해 기간동안 그 값이 증가하였으며, 33개월 경과 후 잔존률은 B₁, B₂, B₃가 각각 58.5%, 47.8%, 75.2%이었다. 마그네슘은 가지의 직경이 작을수록 초기 함량이 높았으며, 33 개월 경과 후 잔존률은 B₁, B₂, B₃에서 각각 44.3%, 57.9%, 47.7%이었다.

• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 1989년도 가을 학술발표회 논문집
• /
• pp.59-64
• /
• 1989

On this condition of steel bridge member having a crack, occasionaly it is improssible to measure of stress history and to extract test specimen. Under this situation, tried to estimate remaining service life from statistical data on traffic and existing results of fatigue test without measuring of stress history and fatigue test. The main results are as following (1) Stress history of simple beam estimated from Montecallo simulation method with probabilistic model of traffic can be use to estimate remaining fatigue life instead of measuring of stress history. (2) In such a case measuring of remaining fatigue life at bridge member haying a crack, influences of RMS model and RMC model on fatigue crack growth rate are not differ without difference of applied stress range. (3) Application of cut off method may be overestimate remaining fatigue life.

• 산업경영시스템학회지
• /
• 제33권3호
• /
• pp.219-224
• /
• 2010

Depreciation accounting has as its main objective, the recovery of the original cost of plant investment less net salvage, over the estimated useful life of that plant. Accuracy of the whole life technique in meeting this objective depends entirely on the original estimates of service life and net salvages for an account. Where the whole life technique has been used and original estimates prove inaccurate, excessive or deficient accumulations in the depreciation reserve frequently occur. To overcome this, the remaining life technique is suggested to better match the challenges of accelerated technology and competition within the regulated environment. The flexibility of the remaining life technique will allow an even chance to provide a complete recovery of the original cost.

• 한국환경복원기술학회지
• /
• 제4권4호
• /
• pp.25-35
• /
• 2001

This study aims to find out the growth characteristics of riparian plants on the artificial floating islands (AFI). Three types of experiments were performed. The vegetation growth were compared by the plant-supporting materials; natural cotton mat, coir mat on the AFI or in the water, and natural soil at the waterfront. Major findings are; 1. The survival rate of riparian plants was 100% on both coir-mat and cotton-matislands, which implies that we may substitute cheaper cotton for expensive coir-mat. 2. Both natural cotton mat and coir mat were good for the growth of plants. Especially, the natural cotton mat was good for Sparganium stoloniferum and Miscanthus sacchariflorus, and the coir mat was good for Typha latifolia. 3. The growth rate of stem and root showed difference between the stem-removed plants and stem-remaining plants. As a whole, the growth rate of stem-removed plants was bigger than the one of stem-remaining plants. 4. The growth rate of plants showed difference between those grown on the AFI and those grown in the water. The growth rate of plant on the AFI was bigger than the one in the water. 5. The growth rate of plants on the AFI was bigger than the one on the natural soil at the waterfront.

• 대한치과의사협회지
• /
• 제58권1호
• /
• pp.45-49
• /
• 2019

Korean society is experiencing a very rapid change in population aging. Oral diseases, including dental caries and periodontal disease, are usually cumulative and make oral health worse with age. Preventing tooth loss through the prevention and treatment of caries and periodontal diseases are essential for retaining oral function later in life. This study aimed to identify the trend in oral health status among elderlies over 65 years old, using major oral health indicators of Health Plan 2020. The fifth, sixth, and seventh Korea National Health and Nutrition Examination Survey (KNHANES V, VI, VII) were used in the present study to estimate the number of remaining natural teeth, the rate of 20 or more natural teeth, the rate of chewing difficulty, and the rate of oral health check-up of elderly. The number of remaining natural teeth increased from 15.6 in 2010 to 17.1 in 2015, and the rate of 20 or more natural teeth also increased from 45.8% in 2010 to 53.7% in 2015. The rate of chewing difficulty was similar but declined a little from 44.3% in 2010 to 42.9% in 2017. Finally, the rate of oral health check-ups of the elderly increased significantly from 12.2% in 2010 to 21.1% in 2017.

• 한국산학기술학회논문지
• /
• 제16권4호
• /
• pp.2401-2406
• /
• 2015

배관은 대형기계설비에서 다양한 작동유체를 운반하는데 사용되는데, 대형시스템의 성능을 유지하기 위해서는 부식된 배관의 잔존 수명을 정확히 예측될 필요가 있다. 하지만, 배관 형상, 물성치, 부식률 등 배관의 수명에 영향을 미치는 요인들의 불확실성이 크기 때문에 부식 잔존 수명을 정확히 예측하기 힘들다. 본 연구에서는 통계적인 접근방법인 베이지안 추론법을 이용하여 부식 잔존 수명을 예측하는 방법을 제안하였다. 여기서, 배관의 파손 확률은 베이지안 법칙을 기반으로 시간에 따른 배관 파손 압력에 관한 사전 정보와 실험데이터를 이용하여 계산되고, 부식 잔존 수명은 10%의 파손 확률을 갖는 경과시간으로 계산되었다. 예제에서는 부식에 영향을 미치는 주요인자로부터 10개와 50개의 데이터를 생성하여 배관의 파손 확률 및 배관의 잔존수명을 예측하였으며 가정한 실제 잔존수명과의 비교를 통해 제안한 방법을 검증하였다.

• 한국치위생학회지
• /
• 제18권2호
• /
• pp.205-215
• /
• 2018

Objectives: The purpose of the study is to investigate the relationship between the number of remaining teeth and bone health status among adults over 65 years old. Methods: The study subjects were 1,843 adults over 65 years old drawn from the Korea National Health and Nutrition Examination Survey (KNHANES) in 2008-2010. Oral health status included the number of remaining teeth, and prosthetic appliance status. Bone health statuses were assessed using dual-energy X-ray absorptiometry (DEXA). Bone health statuses were classified into normal (T-score ${\geq}-1.0$), osteopenia (-2.5 < T-score < -1.0), and osteoporosis (T-score ${\leq}-2.5$). Complex samples chi-square test was used to estimate the relationship between the number of remaining teeth and bone health status, and related factors included in the model were analyzed with the complex samples logistic regression analysis. Results: Using the multinomial logistic regression analytic method, the elderly having 20 or more remaining teeth and those having less than 20 remaining teeth with prosthesis were compared. The latter group had 1.89 times higher rate of being diagnosed as having osteoporosis. Conclusions: This study suggests that oral health is an important factor for geriatric osteoporosis. Therefore, in order to prevent fractures due to osteoporosis and osteoporosis in old age, it is necessary to be aware of the relationship between oral health and osteoporosis, and oral health should be considered when preparing preventive management strategies.

• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 1989년도 봄 학술발표회 논문집
• /
• pp.11-16
• /
• 1989

This paper presents a fatigue reliability model for the reliability-based evaluation of remaining fatigue life of existing rail-road bridges. It is demonstrated that the simple fatigue reliability model based on the Weibull distribution of fatigue life can be extended by incorporating various effects due to the rate of the train-traffic increase and in-service Inspections. The paper also suggests the system fatigue reliability analysis using an approximate formulation and 2nd-order bound solutions. The application of the proposed model to existing rail-road brdiges based on field load tests shows that it may be practically used for the assessment of fatigue reliability, remaining life, and in-service inspection scheduling of existing rail-road bridges.