• Journal of Preventive Medicine and Public Health
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• v.30 no.1 s.56
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• pp.181-193
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• 1997

The purpose of this study was to identify population subgroups with similar patterns of diet quality, physical activity, alcohol consumption and cigarette smoking of Korean. The cluster analysis was conducted using the data from Korea National Health Survey(KNHS) in 1995, which consisted of 5,805 persons. We identified six health behavior typologies : 32.9% of the sample had a good diet but sedentary activity level(good diet lifestyle), 7.2% had high activity level but less diet quality(fitness lifestyle). Individuals in the passive lifestyle cluster(39.1%) had no active health promoting activities but tended to avoid risk taking health behavior such as cigarette smoking and alcohol drinking. 1.1% of the sample were in a drinking cluster, 17.2% in a smoking cluster and 2.5% had a hedonic lifestyle characterized by heavy drinking and smoking. The other characteristics of these lifestyle clusters could be presented by demographic and socioeconomic factors.

• Smart Structures and Systems
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• v.15 no.3
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• pp.609-625
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• 2015

Management of infrastructure stock is essential in sustainability of society, and its analysis and optimization are studied in the light of control system modeling in this paper. At the first part of the paper, cost of stock management is analyzed based on macroscopic statistics on infrastructure stock and economical growth. Stock management burden relative to economy is observed to become larger at low economic growth periods in developed economies. Then, control system modeling of stock management is introduced and by augmenting maintenance actions as control input, dynamic behavior of stock is simulated and compared with existing time history statistics. Assuming steady state conditions, applicability of the model to cross sectional data is also demonstrated. The proposed model is enhanced so that both preventive and corrective maintenance can be included as system inputs, i.e., feedforward and feedback control inputs. Optimal management strategy to achieve specified deteriorated stock level with minimal cost, expressed in terms of preventive and corrective maintenance actions, is derived based on estimated parameter values for corrosion of steel bridges. Relative cost effectiveness of preventive maintenance is shown when target deteriorated stock level is lower.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.10 no.16
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• pp.75-80
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• 1987

This paper is deals with the preventive replacement for the equipment which fails only when the total amount of damage reaches a prespecified failure level. Most of replacement model use time as their decision variable, but it is not appropriate for the cases in which failures dependent on their cumulative damage levels. In this paper, a new type preventive replacement model is introduced in which an equipment is replaced before failure when the cumulative damage reaches a certain level or replaced on failure, whichever occures first. The optimal replacement damage levels which minimize total expected cost are obtained by the Dynamic programming Method when the number of use of the equipment is finite. A numerical example is also presented. The optimal preventive replacement policy when the equipment will be used for a finite time span is also discussed.

• Journal of Society of Preventive Korean Medicine
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• v.6 no.2
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• pp.95-103
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• 2002

In order to study the effect of Luffae fasciculus vascularis(絲瓜絡) on hyperlipidemia, experimental study was performed on Hyperlipidemia induced by Triton WR-1339. Also the level of Total cholesterol, Triglyceride, HDL-cholesterol, Phospholipid and LDL-cholesterol were measured. The results are summarized as follow: In the model of hyperlipidemia Rats induced by Triton WR-1339, luffae fasciculus vascularis(絲瓜絡) had significantly decreasing effects on total cholesterol, triglyceride, phospholipid, LDL-cholesterol in serum and increasing effects on HDL-cholesterol level in serum but were not significant. These results show that Luffae fasciculus vascularis(絲瓜絡) has significantly inhibitory effects on hyperlipidemia and that it could be clinically applied for hyperlipidemia.

• Environmental Analysis Health and Toxicology
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• v.28
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• pp.15.1-15.8
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• 2013

Objectives The aim of this study was to determine the association between low-level mercury exposure and neurobehavioral functions in adults living in coastal regions of Korea. Methods We selected 172 adults aged 20-65 years living in a city in the coastal region of Korea. A sociodemographic survey was conducted, mercury levels in the blood, urine, and hair were measured, and the associations according to computerized neurobehavioral tests were determined using univariate analysis. After adjustment for associated variables, a multivariate linear regression analysis was performed. Results The geometric mean mercury levels in the blood, urine, and hair were $5.41{\mu}g/L$ (range, $0.00-15.84{\mu}g/L$), $1.17{\mu}g/g$-creatinine (range, $0.00-32.86{\mu}g/g$-creatinine), and 1.37 mg/kg (range, 0.42-6.56 mg/kg), respectively. Variables that were associated with simple reaction time according to the neurobehavioral test results were age and urine mercury level. Variables associated with choice reaction time were the recent use of Korean traditional medicine and urine mercury level. Variables associated with the right-hand finger tapping speed test were age, gender, smoking behavior, education level, monthly household income, and urine mercury level. Variables associated with the left-hand finger tapping speed test were age, gender, education level, and urine mercury level. After adjustment for associated variables, there was no significant association between urine mercury level and simple reaction time (${\beta}=25.96$; p =0.47), choice reaction time (${\beta}=50.37$; p =0.32), or the number of left-hand finger taps (${\beta}=-1.54$; p =0.21). However, urine mercury level was significantly associated with the number of right-hand finger taps (${\beta}=-3.86$; p =0.01). Conclusions We found no evidence that low-level mercury exposure in adults is associated with deficits in neurobehavioral functions. A longer follow-up study is required to confirm this conclusion.

• 대한예방의학회:학술대회논문집
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• 1995.10a
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• pp.323-324
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• 1995

• 대한예방의학회:학술대회논문집
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• 2005.10a
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• pp.488-488
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• 2005

• Journal of Preventive Medicine and Public Health
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• v.9 no.1
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• pp.87-94
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• 1976

In order to study the chelating action of d-penicillamine on lead and the possibility of its application to the provocation test for diagnosis of lead poisoning, urinary excretion of lead was measured from 24-hour urine samples before, during and after administration of d-penicillamine by oral route for 5 days on 18 lead workers. The results were as follows: 1. Oral d-penicillamine 600 mg/day raised the excretion of urinary lead by approximately 3 times as compared with initial urinary lead level. 2. Initial urinary lead level was the better indicator of urinary lead excretion in d-penicillamine administration than initial blood lead ${\delta}-ALA$ and hemoglobin level. 3. Oral d-penicillamine may be quite useful in provocation test for lead poisoning.

• Journal of Preventive Medicine and Public Health
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• v.24 no.3 s.35
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• pp.459-461
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• 1991

• Journal of Korean Society for Quality Management
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• v.29 no.3
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• pp.39-48
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• 2001

Preventive maintenance(PM) is an action taken on a repairable system while it is still operating, which needs to be carried out in order to keep the system at the desired level of successful operation. In this paper, we consider a Bayesian approach to determine an optimal periodic preventive maintenance policy. When the failure time is Weibull distribution with uncertain parameters, a Bayesian approach is established. Some numerical examples are presented for illustrative purpose.