• Title/Summary/Keyword: Decay Rate Method

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A study on OHIP-14 and EQ-5D of residents in some rural areas (일부 농촌지역 주민들의 OHIP-14와 EQ-5D에 관한 연구)

  • Lee, Eun-Gyeong;Park, Jeong-Hee;Park, Jeong-Ran;Park, Jae-Yong
    • Journal of Korean society of Dental Hygiene
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    • v.11 no.2
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    • pp.197-211
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    • 2011
  • Objectives : OHIP-14 and EQ-5D were used, targeting the residents of farming communities to identify the elements that influence oral cavity's health and quality of life due to health and to identify the importance of oral cavity's health in order to increase health of adults' oral cavity and quality of life via improved health. Methods : This research was conducted from July 17th, 2010 to August 16th, 2010 targeting 600 residents in Goryeong-gun, Gyeongsangbuk-do, aging over 40. The data has been analyzed using Mann-Whitney U test, Kruskal-Wallis test and hierarchical multiple regression through SPSS Win Program 18.0 version. Results : 1. OHIP-14 and EQ-5D based on general characteristics showed lower oral health-related quality of life and health-related quality of life on the following cases: women (p=0.004, p<0.001), older (p<0.001, p<0.001), lower scholastic ability (p<0.001, p<0.001), lower average of average spending money (p<0.001, p<0.001), higher number of chronic disease (p<0.001, p<0.001), less drinking (p=0.012, p=0.008), lower perceived oral health and health status (p<0.001, p<0.001) and non smoking showed only EQ-5D (p<0.001). 2. OHIP-14 and EQ-5D based on oral health behavior showed lower oral health-related quality of life and health-related quality of life on the following cases: no periodic oral check-up (p<0.001, p<0.001), less experience of oral health education (p<0.001, p<0.001), horizontal tooth-brushing method(p<0.001, p<0.001) and lower frequency of tooth-brushing showed only OHIP-14 (p=0.042). OHIP-14 and EQ-5D based on oral health status and subjective oral symptom showed lower oral health-related quality of life and health-related quality of life on following cases: number of existing tooth less than 20 (p<0.001, p<0.001), the number of missing teeth more than 9 (p<0.001, p=0.044), DMFT (Decay, Missing, Filling Teeth) index more than 18 (p<0.001, p<0.001), wears denture (p<0.001, p<0.001), edentulous (p<0.001, p=0.002), have xerostomia (p<0.001, p<0.001) and have chewing discomfort (p<0.001, p<0.001). 3. Factors affecting OHIP-14 were gender, age, perceived oral health status, perceived health status, number of existing teeth, dental status, xerostomia and chewing discomfort, and the of reliability (how well it explains) the final model was 48.7%. EQ-5D showed relevance on gender, age, presence of chronic disease, perceived health status, xerostomia, chewing discomfort and oral health-related quality of life, and the reliability of the final model was 42.9%. Conclusions : In order to improve the quality of life of ruralists, oral health needs to be improved or remained by increasing the rate of possession of the existing teeth and preventing the loss of teeth. In order to do so, improvement of accessibility of dental clinic, change of direction from treatment-centered to prevention-centered health care system, development of oral health education program and various oral health care policies which would vitalize continuous oral health care system are considered to be necessary.

Development of the Monte Carlo Simulation Radiation Dose Assessment Procedure for NORM added Consumer Adhere·Non-Adhere Product based on ICRP 103 (ICRP 103 권고기반의 밀착형·비밀착형 가공제품 사용으로 인한 몬테칼로 전산모사 피폭선량 평가체계 개발)

  • Go, Ho-Jung;Noh, Siwan;Lee, Jae-Ho;Yeom, Yeon-Soo;Lee, Jai-Ki
    • Journal of Radiation Protection and Research
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    • v.40 no.3
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    • pp.124-131
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    • 2015
  • Radiation exposure to humans can be caused by the gamma rays emitted from natural radioactive elements(such as uranium, thorium and potassium and any of their decay products) of Naturally Occurring Radioactive Materials(NORM) or Technologically Enhanced Naturally Occurring Radioactive Materials(TENORM) added consumer products. In this study, assume that activity of radioactive elements is $^{238}U$, $^{235}U$, $^{232}Th$ $1Bq{\cdot}g^{-1}$, $^{40}K$ $10Bq{\cdot}g^{-1}$ and the gamma rays emitted from these natural radioactive elements radioactive equilibrium state. In this study, reflected End-User circumstances and evaluated annual exposure dose for products based on ICRP reference voxel phantoms and ICRP Recommendation 103 using the Monte Carlo Method. The consumer products classified according to the adhere to the skin(bracelet, necklace, belt-wrist, belt-ankle, belt-knee, moxa stone) or not(gypsum board, anion wallpaper, anion paint), and Geometric Modeling was reflected in Republic of Korea "Residential Living Trend-distributions and Design Guidelines For Common Types of Household.", was designed the Room model($3m{\times}4m{\times}2.8m$, a closed room, conservatively) and the ICRP reference phantom's 3D segmentation and modeling. The end-user's usage time assume that "Development and Application of Korean Exposure Factors." or conservatively 24 hours; in case of unknown. In this study, the results of the effective dose were 0.00003 ~ 0.47636 mSv per year and were confirmed the meaning of necessary for geometric modeling to ICRP reference phantoms through the equivalent dose rate of belt products.

Development of pallet-scale modified atmosphere packaging for 'Tabor' tomatoes (토마토 'Tabor' 품종의 파렛트 단위 MAP 적용 연구)

  • Park, Jong Woo;Kim, Jinse;Park, Seok Ho;Choi, Dong Soo;Choi, Seung Ryul;Kim, Yong Hoon;Lee, Soo Jang;Park, Chun Wan;Lee, Jung Soo
    • Food Science and Preservation
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    • v.23 no.5
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    • pp.614-622
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    • 2016
  • This study was carried out to investigate the effect of modified-atmosphere packaging (MAP) on the quality change of "Tabor" tomatoes during long-term exportation periods. Hydroponics tomatoes were harvested at the turning stage, sorted, and box packed and then packaged in nylon film with a pallet. The packaged pallet was filled with a gas composition (5% $O_2$, 1% $CO_2$, and 94% $N_2$) and stored at $10^{\circ}C$ for three weeks. The quality changes in weight loss, firmness, color, acidity, soluble solids, and microorganism growth were measured every 7 day interval. During the initial storage, the pallet-scale MAP showed slightly higher weight loss and firmness changes when compared to the conventional pallet. The total color change (${\Delta}E$) during ripening was delayed 10% under MAP storage. Acidity, soluble solids and phenolic compound contents decreased with increases in storage time regardless of the storage method; however, the quality changes of tomatoes were delayed in the MAP pallet. Furthermore, the decay rate of the pallet-scale MAP stored for 14 days was less than that of the conventional pallet, and the number of microorganisms was approximately 30% lower in the pallet-scale MAP, showing a positive effect on marketability. These results suggested that the pallet-scale MAP of tomatoes could ensure higher quality and longer storage periods than conventional pallet storage.

Effects of Chitosan, Grain Amino Acid and Wood Vinegar Foliar Spray on the Quality and Storability of Grapes(Campbell Early) (키토산, 곡물아미노산, 목초액의 엽면살포가 포도(Campbell Early)의 품질 및 저장성에 미치는 영향)

  • Ju, In-Ok;Jung, Gi-Tai;Cheong, Seong-Soo;Moon, Young-Hun;Ryu, Jeong;Choi, Joung-Sik
    • Food Science and Preservation
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    • v.14 no.2
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    • pp.119-123
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    • 2007
  • Sprays containing chitosan, grain amino acids, or wood vinegar, were applied to vine leaves of the Campbell Early grape variety, and effects on the quality and storability of grapes were investigated. Weights of grape clusters and individual bemies did not differ significantly from the values seen when traditional agnicultural chemical treatment was used. The percentage of clusters over 300g in weight was, however, higher after spraying with chitosan, grain amino acids, or wood vinegar, than after agricultural chemical treatment, Grape moisture contents, levels of soluble solids, and reducing sugar concentrations, did not differ when the traditional treatment and the newer sparys were compared. Among minerals, the levels of potassium, iron and zinc measured in fresh grapes were increased by the clitosan, grain amino acids, and wood vinegar spray. After 8 weeks of MA storage, reducing sugar levels decreased, and titratable acidities increased, compared to levels measured at the beginning of storage. This was true regardless of the method of vine treatment the hardness of berries decreased slightly over 4-6 weeks of storage, and increased thereafter. The weight losses of grapes were relatively low(0.28-0.35%) on storage after any vine treatment tested. Grapes from vines sprayed with chitosan or grain amino acids showed a lower decay rate than did fruit from vines that had received a traditional agricultural chemical treatment. Sensory evaluation results indicated that the marketability of grapes from vines treated with traditional agricultural chemicals was better than that of grapes from vines sprayed with chitosan, grain amino acids, or wood vinegar.

A basic study on explosion pressure of hydrogen tank for hydrogen fueled vehicles in road tunnels (도로터널에서 수소 연료차 수소탱크 폭발시 폭발압력에 대한 기초적 연구)

  • Ryu, Ji-Oh;Ahn, Sang-Ho;Lee, Hu-Yeong
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.23 no.6
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    • pp.517-534
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    • 2021
  • Hydrogen fuel is emerging as an new energy source to replace fossil fuels in that it can solve environmental pollution problems and reduce energy imbalance and cost. Since hydrogen is eco-friendly but highly explosive, there is a high concern about fire and explosion accidents of hydrogen fueled vehicles. In particular, in semi-enclosed spaces such as tunnels, the risk is predicted to increase. Therefore, this study was conducted on the applicability of the equivalent TNT model and the numerical analysis method to evaluate the hydrogen explosion pressure in the tunnel. In comparison and review of the explosion pressure of 6 equivalent TNT models and Weyandt's experimental results, the Henrych equation was found to be the closest with a deviation of 13.6%. As a result of examining the effect of hydrogen tank capacity (52, 72, 156 L) and tunnel cross-section (40.5, 54, 72, 95 m2) on the explosion pressure using numerical analysis, the explosion pressure wave in the tunnel initially it propagates in a hemispherical shape as in open space. Furthermore, when it passes the certain distance it is transformed a plane wave and propagates at a very gradual decay rate. The Henrych equation agrees well with the numerical analysis results in the section where the explosion pressure is rapidly decreasing, but it is significantly underestimated after the explosion pressure wave is transformed into a plane wave. In case of same hydrogen tank capacity, an explosion pressure decreases as the tunnel cross-sectional area increases, and in case of the same cross-sectional area, the explosion pressure increases by about 2.5 times if the hydrogen tank capacity increases from 52 L to 156 L. As a result of the evaluation of the limiting distance affecting the human body, when a 52 L hydrogen tank explodes, the limiting distance to death was estimated to be about 3 m, and the limiting distance to serious injury was estimated to be 28.5~35.8 m.