• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2002.11a
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• pp.528-533
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• 2002

인터넷 인프라의 보급과 이용인구의 급속한 증가는 off-line을 통해서 물리적으로 획득하던 다양한 정보와 자료를 인터넷을 통해서 쉽고 빠르게 이용할 수 있는 서비스를 창출하고 있다. 그러나 이와 같은 서비스를 통해서 제공되는 컨텐츠의 저작권 문제와 불법 복제 등과 같은 피해도 함께 증가하고 있다. 이런 문제를 해결하기 위해서는 컨텐츠에 접근하고 이용할 수 있는 자격을 가지고 있는 사용자만이 해당 컨텐츠를 정상적으로 이용할 수 있도록 하는 Access Control(AC) 기술이 함께 연구되고 있다. 현재 상용화되어 있는 CAS와 DRM은 PBT 형태의 대표적인 AC 기술이라 할 수 있다. 본 논문에서는 [5]에서 제시된 PFT 기반의 AC를 위한 Security Architecture를 살펴보고, 효과적인 운영을 위한 PFT 기반의 새로운 AC 구조를 제시한다.

• Journal of Preventive Medicine and Public Health
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• v.21 no.2 s.24
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• pp.245-250
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• 1988

For the evaluation of change of FVC and $FEV_1$ after discontinuance of bronchodilator in the coal workers' pneumoconiosis patients, 17 pairs of patients were selected. They were matched by the age(${\pm}5$ y.o.) and the type of ventilatory impairment. Pulmonary function was measured 2 times bimonthly before and after the drug discontinuance discontinued after measurement of PFT for 2 times. In case group the bronchodilator was discontinued after measurement of PFT for 2 times. In control group there was no interruption of medication. FVC, $FEV_1$ decreased in both group as measurement progress. Simple linear regression coefficients against the month of measurement were calculated in both group and tested for parallelism between two groups. The results of test revealed that both regression coefficients were parallel. So in conclusively, discontinuance of medication of bronchodilator for coal workers pneumoconiosis patients has no effect on the decreasing rate of FVC, $FEV_1$.

• Toxicological Research
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• v.26 no.4
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• pp.329-337
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• 2010

Inhaled inorganic dusts, such as coal, can cause inflammation and fibrosis in the lungs, known as pneumoconiosis. Diagnosis of pneumoconiosis depends on morphological changes by radiological findings and functional change by pulmonary function test (PFT). Unfortunately, current diagnostic findings are limited only to lung fibrosis, which is usually irreversibly progressive. Therefore, it is important that research on potential and prospective biomarkers for pneumoconiosis should be conducted prior to initiation of irreversible radiological or functional changes in the lungs. Analytical techniques using exhaled breath condensate (EBC) or exhaled gas are non-invasive methods for detection of various respiratory diseases. The objective of this study is to investigate the relationship between inflammatory biomarkers, such as EBC pH or fractional exhaled nitric oxide ($FE_{NO}$), and pneumoconiosis among 120 retired coal miners (41 controls and 79 pneumoconiosis patients). Levels of EBC pH and FENO did not show a statistically significant difference between the pneumoconiosis patient group and pneumoconiosis patients with small opacity classified by International Labor Organization (ILO) classification. The mean concentration of $FE_{NO}$ in the low percentage $FEV_1$ (< 80%) was lower than that in the high percentage (80% $\leq$) (p = 0.023). The mean concentration of $FE_{NO}$ in current smokers was lower than that in non smokers (never or past smokers) (p = 0.027). Although there was no statistical significance, the levels of $FE_{NO}$ in smokers tended to decrease, compared with non smokers, regardless of pneumoconiosis. In conclusion, there was no significant relationship between the level of EBC pH or $FE_{NO}$ and radiological findings or PFT. The effects between exhaled biomarkers and pneumoconiosis progression, such as decreasing PFT and exacerbation of radiological findings, should be monitored.

• Journal of Chest Surgery
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• v.33 no.10
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• pp.798-805
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• 2000

Background : the prediction on changes in the lung function after lung surgery would be an important indicator in terms of the operability and postoperative complications. In order to predict the postoperative FEV1 - the commonly used method for measuring changes in lung function- a comparison between the quantitative CT and the perfusion lung scan was made and proved its usefulness. Material and Method : The subjects included 22 patients who received perfusion lung scan and quantitative CT preoperatively and with whom the follow-up of PFT were possibles out of the pool of patients who underwent right lobectomy or right pneumonectomy between June of 1997 and December of 1999. The FEV1 and FVC were calibrated by performing the PFT on each patient and then the predicted FEV1 and FVC were calculated after performing perfusion lung scan and quantitative CT postoperatively. The FEV1 and FVC were calibrated by performing the PFT after 1 week and after 3 momths following the surgery. Results : There was a significant mutual scan and the actual postoperative FEV1 and FVC at 1 week and 3 months. The predicted FEV1 and FVC(pneumonectomy group : r=0.962 and r=0.938 lobectomy group ; r=0.921 and r=913) using quantitative CT at 1 week postoperatively showed a higher mutual relationship than that predicted by perfusion lung scan(pneumonectomy group : r=0.927 and r=0.890 lobectomy group : r=0.910 and r=0.905) The result was likewise at 3 months postoperatively(CT -pneumonectomy group : r=0.799 and r=0.882 lobectomy group : r=0.934 and r=0.932) Conclusion ; In comparison to perfusion lung scan quantitative CT is more accurate in predicting lung function postoperatively and is cost-effective as well. Therefore it can be concluded that the quantitative CT is an effective method of replacing the perfusion lung scan in predicting lung function post-operatively. However it is noted that further comparative analysis using more data and follow-up studies of the patients is required.

• Radiation Oncology Journal
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• v.31 no.1
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• pp.34-40
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• 2013

Purpose: To evaluate the predictive factors of radiation pneumonitis (RP) and associated changes in pulmonary function after definitive concurrent chemoradiotherapy (CCRT) in patients with non-small cell lung cancer (NSCLC). Materials and Methods: Medical records of 60 patients with NSCLC who received definitive CCRT were retrospectively reviewed. Dose volumetric (DV) parameters, clinical factors, and pulmonary function test (PFT) data were analyzed. RP was graded according to the CTCAE ver. 4.0. Percentage of lung volume that received a dose of threshold (Vdose) and mean lung dose (MLD) were analyzed for potential DV predictors. PFT changes were calculated as the difference between pre-RT and post-RT values at 3, 6, and 12 months after RT. Results: Twenty-two patients (37%) developed grade ${\geq}2$ RP. Among clinical factors, tumor location in lower lobe was associated with RP. Among the DV parameters, only MLD >15 Gy was associated with grade ${\geq}2$ RP. There were statistically significant decreases in PFT at all points compared with pre-RT values in grade ${\geq}2$ RP group. MLD was associated with forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) changes at 6 and 12 months. V10 was associated with FVC changes at 12 months. V20 and V30 were associated with FEV1 changes at 6 months and FVC changes at 12 months. Conclusion: After definitive CCRT in patients with NSCLC, MLD >15 Gy and lower lobe tumor location were predictors of grade ${\geq}2$ RP. Pulmonary functions were decreased after CCRT and the magnitude of changes was associated with DV parameters.

• Archives of Pharmacal Research
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• v.20 no.3
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• pp.247-252
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• 1997

Perfluorotolyl (PFT)-ether and perfluorotoly-trimethylsilyl (PFT-TMS) ether derivatives of oestrone, $17{\alpha}$- and $17{\beta}$oestradiol were prepared under phase transfer conditons. The former derivatives under negative ion chemical ionization conditions gave significant ions in the mass spectrometer but $17{\alpha}$- and $17{\beta}$ -oestradiol gave poor resolution. However, the PFT-TMS derivatives of 17.${\alpha}$- and$17{\beta}$-oestradiol showed good resolution. These derivatives were used for the analysis of oestrogens in bovine aqueous humour, vitreous humour and retina. The mean $({\pm}SEM)$ concentrations of oestrone in bovine aqueous humour (n=18), vitreous humour (n=18) and bovine retina (n=4) were $0.47{\pm}0.11$, $0.46{\pm}0.14$ and $1.10{\pm}0.24 ng.ml^{-1}$, respectively. $17{\alpha}$-Oestradiol was detected in 16 out of 18 samples of bovine aqueous humour and vitreous humour and the mean $({\pm}SEM)$ concentrations were $0.30{\pm}0.10$ and $0.08{\pm}0.02 ng.ml^{-1}$, respectively. The mean $({\pm}SEM)$ concentration of 17.betha.-oestradiol in aqueous humour (n=7) and vitreous homour (n=11) $0.83{\pm}0.26 ng ml^{-1}$ and $0.39{\pm}0.09 ng ml^-1$, respectively. In retina the concentrations of both steroids were below the detection limit.

• Annals of Rehabilitation Medicine
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• v.42 no.6
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• pp.798-803
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• 2018

Objective To investigate the relationship between peak cough flow (PCF), pulmonary function tests (PFT), and severity of dysphagia in patients with ischemic stroke. Methods This study included patients diagnosed with ischemic stroke, who underwent videofluoroscopic swallowing study (VFSS), PCF and PFT from March 2016 to February 2017. The dysphagia severity was assessed using the videofluoroscopic dysphagia scale (VDS). Correlation analysis of VDS, PFT and PCF was performed. Patients were divided into three groups based on VDS score. One-way ANOVA of VDS was performed to analyze PCF, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and age among the different groups. Results The correlation coefficients of VDS and PCF, VDS and FVC, and VDS and FEV1 were -0.836, -0.508, and -0.430, respectively, all of which were statistically significant at the level of p<0.001. The one-way ANOVA indicated statistically significant differences in PCF, FVC, FEV1, and age among the VDS groups. Statistically significant differences in VDS and age were observed between aspiration pneumoia and non-aspiration pneumonia groups. Conclusion Coughing is a useful factor in evaluating the risk of aspiration in dysphagia patients. Evaluation of respiratory and coughing function should be conducted during the swallowing assessment of patients with ischemic stroke.

• The Journal of Internal Korean Medicine
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• v.37 no.3
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• pp.484-494
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• 2016

Objective: This study was designed to analyze the treatment effects of Chungsangboha-tang through retrospective chart reviews.Methods: Fifty-one outpatients who had visited the Allergy, Immune & Respiratory System Division at the Kyung Hee Korean Medicine Hospital and who had taken Chungsangboha-tang from February 1, 2006, to February 1, 2016, had their basic medical records and examinationsretrospectively reviewed with respect to IgE, eosinophil, AST, and ALT. The PFT results of 11 patients were also investigated with respect to FEV1, FVC, and FEV1/FVC.Results: The percentage of males and females was 49.02% and 50.98%, respectively. The past histories of patients included asthma (66.67%), unspecified cough (21.57%), COPD (9.80%), allergic rhinitis (7.84%), and others. The subjective symptoms included cough (82.35%), sputum (39.22%), dyspnea (37.25%), and others. The most numerous pattern identification was wheezing dyspnea. IgE was significantly reduced, and eosinophil had a reduced tendency after 116.76±160.40 days of taking Chungsangboha-tang. PFT results also significantly increased after 213.09±266.62 days, while AST and ALT results showed a reduced tendency. In the asthmatic group, IgE also showed a reduced tendency. In particular, IgE was significantly reduced in patient groups taking medicine for more than 12 weeks.Conclusions: The conditions of patients with chronic pulmonary disease such as asthma and COPD significantly improved with Chungsangboha-tang after more than 12 weeks.

• Journal of The Korean Society of Integrative Medicine
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• v.12 no.1
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• pp.27-39
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• 2024

Purpose : Smoking is a major factor in chronic obstructive pulmonary disease (COPD), but the effect of electrical cigarette smoking on COPD development is still uncertain. This study aimed to compare the functions of airways and lungs exposed to combustible cigarettes and electrical cigarettes based on the pulmonary function test (PFT) results from the Korean National Health and Nutrition Examination Survey (NHANES). Methods : This study used data from 8,942 participants with PFT results out of 47,309 total subjects from the 6th to 8th Korean NHANES (2014-2015, 2016-2018, and 2019, respectively). Individuals with diseases such as cancer, ex-smokers, and dual tobacco users were excluded. The PFT results were analyzed according to the COPD diagnostic criteria. After adjusting for confounding variables, a complex sample generalized linear model ANOVA test was performed to investigate the association between PFT results and combustible smoker or electrical cigarette user groups. Results : In an analysis based on the obstructive ventilatory disorders (forced expiratory volume in 1 second[FEV₁]/forced vital capacity[FVC]<.7), combustible cigarette smokers showed a 3.46 times higher risk of COPD compared to non-smokers, while electrical cigarette smokers exhibited no significant difference in terms of COPD-related risks compared to non-smokers. FEV₁ showed a negative relation with combustible cigarette smokers as reported elsewhere (B=-.07, p<.001). FEV₁/FVC was negatively related to both combustible cigarette smokers (B=-.03, p<.001) and electrical cigarette smokers (B=-.02, p<.001). Conclusion : FEV₁/FVC decreases were observed in the long-term exposure to both combustible and electrical cigarettes. The lower FEV₁ in the combustible cigarette group implies the worsening of the severity of COPD, suggesting more damage to the airways and lungs in the short term. Therefore, the temporary electrical cigarettes use for the transition period in order to smoking cessation potentially aids to reduce the harmful effect of combustible cigarettes in COPD development.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.39.1-39.14
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• 2023

Background: Diseases affecting the lungs and airways contribute significantly to the global burden of disease. The problem in low- and middle-income countries appears to be exacerbated by a shift in global manufacturing base to these countries and inadequate enforcement of environmental and safety standards. In Ghana, the potential adverse effects on respiratory function associated with occupational wood dust exposure have not been thoroughly investigated. Methods: Sixty-four male sawmill workers and 64 non-woodworkers participated in this study. The concentration of wood dust exposure, prevalence and likelihood of association of respiratory symptoms with wood dust exposure and changes in pulmonary function test (PFT) parameters in association with wood dust exposure were determined from dust concentration measurements, symptoms questionnaire and lung function test parameters. Results: Sawmill workers were exposed to inhalable dust concentration of 3.09 ± 0.04 mg/m³ but did not use respirators and engaged in personal grooming habits that are known to increase dust inhalation. The sawmill operators also showed higher prevalence and likelihoods of association with respiratory symptoms, a significant cross-shift decline in some PFT parameters and a shift towards a restrictive pattern of lung dysfunction by end of daily shift. The before-shift PFT parameters of woodworkers were comparable to those of non-woodworkers, indicating a lack of chronic effects of wood dust exposure. Conclusions: Wood dust exposure at the study site was associated with acute respiratory symptoms and acute changes in some PFT parameters. This calls for institution and enforcement of workplace and environmental safety policies to minimise exposure at sawmill operating sites, and ultimately, decrease the burden of respiratory diseases.