• Title/Summary/Keyword: Water quality changes

Search Result 1,285, Processing Time 0.031 seconds

Efficient Verification of X-ray Target Replacement for the C-series High Energy Linear Accelerator

  • Cho, Jin Dong;Chun, Minsoo;Son, Jaeman;An, Hyun Joon;Yoon, Jeongmin;Choi, Chang Heon;Kim, Jung-in;Park, Jong Min;Kim, Jin Sung
    • Progress in Medical Physics
    • /
    • v.29 no.3
    • /
    • pp.92-100
    • /
    • 2018
  • The manufacturer of a linear accelerator (LINAC) has reported that the target melting phenomenon could be caused by a non-recommended output setting and the excessive use of monitor unit (MU) with intensity-modulated radiation therapy (IMRT). Due to these reasons, we observed an unexpected beam interruption during the treatment of a patient in our institution. The target status was inspected and a replacement of the target was determined. After the target replacement, the beam profile was adjusted to the machine commissioning beam data, and the absolute doses-to-water for 6 MV and 10 MV photon beams were calibrated according to American Association of Physicists in Medicine (AAPM) Task Group (TG)-51 protocol. To verify the beam data after target replacement, the beam flatness, symmetry, output factor, and percent depth dose (PDD) were measured and compared with the commissioning data. The difference between the referenced and measured data for flatness and symmetry exhibited a coincidence within 0.3% for both 6 MV and 10 MV, and the difference of the PDD at 10 cm depth ($PDD_{10}$) was also within 0.3% for both photon energies. Also, patient-specific quality assurances (QAs) were performed with gamma analysis using a 2-D diode and ion chamber array detector for eight patients. The average gamma passing rates for all patients for the relative dose distribution was $99.1%{\pm}1.0%$, and those for absolute dose distribution was $97.2%{\pm}2.7%$, which means the gamma analysis results were all clinically acceptable. In this study, we recommend that the beam characteristics, such as beam profile, depth dose, and output factors, should be examined. Further, patient-specific QAs should be performed to verify the changes in the overall beam delivery system when a target replacement is inevitable; although it is more important to check the beam output in a daily routine.

Changes in Days to Drying and Some Chemical Components by Different Drying Methods in Paeoniae radix (건조방법에 따른 작약근 건조 소요일수 및 성분 변화)

  • ;Kwang-He Kang
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.41 no.3
    • /
    • pp.362-369
    • /
    • 1996
  • Seven different drying methods were tested in peony roots of Euisung cultivar, harvested in February, in three year's old plant. The roots were selected in length and diameter and half of the samples were removed cork-layers to compare the effects of cork-layer in processing of drying. The 3$0^{\circ}C$ heat drying without cork-layer reduced in days to drying by five days compared to those of the with cork-layers at the same temperature. The 5$0^{\circ}C$ heat drying after cork-layers removed was the most effective in days to drying. In quality of skin color of the 5$0^{\circ}C$ heating was worse to compare with the lower drying temperature. In the drying at room temperature and the heat drying at lower temperature, the paeoniflorin content in drying after cork-layers removed were higher than that of the drying with cork-layers. However, in the boiling water treatment, the paeoniflorin contents in drying after cork-layers removed were lower than those of with cork-layers. In heat drying, paeoniflorin content showed a decreasing tendency to increase of drying temperature. Total sugars in the peony roots showed a decreasing tendency according to the drying temperature increasing, but starch concentration showed a increasing tendency at the same condition. Concentrations of crude protein, crude fiber and crude ash were showed no differences in various drying methods and the materials with or without cork-layers. Relationships between the paeoniflorin and total sugars, and the paeoniflorin and starch were different significantly by the materials of cork-layers removed or not. The 30~4$0^{\circ}C$ heat drying without cork-layers was the most advisable condition for drying in paeoniflorin concentration, days to drying and skin color after drying.

  • PDF

Effect of Microbubble Ozonation Process on Performance of Biological Reactor System for Excess Sludge Solubilisation (마이크로버블오존을 이용한 잉여슬러지 가용화 처리가 생물반응조의 성능에 미치는 영향)

  • Lee, Shun-Hwa;Jung, Kye-Ju;Kwon, Jin-Ha;Lee, Se-Han
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.33 no.2
    • /
    • pp.113-119
    • /
    • 2011
  • The study purpose was to examine an effect of zero emission of excess sludge on biological reactor and treated water quality within the biological reactor in the process of biological treatment combined with excess sludge reduction system with ozone. Under an ozone injection rate 0.03 g $O_3/g$ SS, Sludge Disintegration Number (SDN) 3 and less than pH 4 as pre-treatment process, it was possible to maintain a stable biological treatment process without sludge disintegration. In the test of $OUR_{max}$, of sludge, its value was hardly under the condition of ozone injection rate 0.03 g $O_3/g$ SS. There were almost no changes of MLVSS/MLSS within biological reactor followed by a solubilization of excess sludge. Accumulation of microorganism within biological reactor was also not observed. After solubilization of excess sludge, an increase for organic matter and SS concentrations of an effluent was not observed and T-N concentration was reduced by increasing nitrification and denitrification rate within biological reactor. Most of T-P was not removed by zero emission of excess sludge and was leaked by being included in effluents.

Changes in Physicochemical Properties of Paprika by Intense Pulsed Light Treatment (광펄스 처리에 의한 파프리카의 이화학적 변화)

  • Hong, Hee Joung;Kim, Ae-Jin;Park, Hee Ran;Shin, Jung-Kue
    • Korean Journal of Food Science and Technology
    • /
    • v.45 no.3
    • /
    • pp.339-344
    • /
    • 2013
  • Application of intense pulsed light (IPL) treatment is an emerging technology with interesting prospects in food preservation. However, information concerning the factors affecting the inactivation of microorganisms and their impact on the quality of fresh-cut food is scarce. In this study, the effects of IPL treatment on the microbial inactivation and physicochemical change in paprika were determined. The viability of bacteria in paprika treated with IPL decreased slightly with the treatment time. In addition, water content was slightly decreased after IPL treatment regardless of the color of paprika. However, except in red paprika, sugar content increased after IPL treatment. The pH of paprika increased in all samples, and the polyphenol content decreased with treatment time, but these differences were very small. After IPL treatment of paprika, vitamin C content increased in yellow and red samples. Hunter color values-lightness (L), redness (a), and yellowness (b)-increased in red paprika, but all values decreased in orange paprika.

Optimization for Preparation of Perilla Jangachi according to Steaming Time and Onion Contents (찌는 시간과 양파 첨가량에 따른 깻잎장아찌의 최적화)

  • Lee, Hye-Ran;Nam, Sang-Min;Lee, Jong-Mee
    • Journal of the Korean Society of Food Culture
    • /
    • v.17 no.5
    • /
    • pp.653-662
    • /
    • 2002
  • Korean native Perilla Jangachi (salted and fermented vegetable) is popular and well-known but little study on its composition and most palatable condition has been reported. This study was performed to observe the change in the contents of chemical components and sensory evaluation of Perilla Jangachi which was prepared through two processing. First, as a pretreatment, Perilla leaves were soaked in salt water. The optimal level of salt concentration and soaking time (salt 4%, soaking time 42hours) was determined. Second, soaked Perilla Jangachi was steamed and then fermented in various ingredients like soy sauce, sugar, onion and so on. In this study, Perilla Jangachi was made by 3 levels of steaming time(30 seconds, 60 seconds, 90 seconds) and onion contents (10%, 30%, 50%). The optimal level of onion contents and steaming time was determined with the results of sensory evaluation by response surface methodology and analysis of composition. Sodium contents were decreased as the levels of onion contents were increased. Flavonoids contents weren't increased although contents of onion were increased. But they were influenced on steaming time that as the levels of steaming time were shortened, flavonoids contents were increased. To lengthen the shelf-life of Perilla Jangachi, the activities of enzyme peroxidase - which changes Jangachi's quality bad - by various levels of steaming time were measured. After steaming 50 seconds, peroxidase became inactive. Reducing sugar contents were decreased relying on either increased steaming time and onion contents. While steaming 30 seconds and 10% onion contents, the content of reducing sugar was 0.858% but steaming 90 seconds and 50% onion contents, it became 0.372%. Among the sensory attributes, brownness was increased as onion contents increased and steaming more than 60 seconds. Saltiness, sweetness, perilla flavor were greater relying on decreased onion contents. Toughness was decreased as both the amounts of onion and steaming time were increased. With this results, the most optimal adding level of onion content and steaming time was determined. Steaming 72 seconds and adding onion 27% was established as a optimal condition of Perilla Jangachi.

The Economic Impact of Contaminated and Noxious Sites : A Meta Analysis (오염-유해시설의 경제적 영향 : 메타분석)

  • Won, Doo Hwan
    • Environmental and Resource Economics Review
    • /
    • v.17 no.1
    • /
    • pp.165-196
    • /
    • 2008
  • This paper reports a quantitative meta analysis of the economic impacts of localized noxious and contaminated sites. Using either hedonic property value or stated preference methods, economists have studied the effects of contamination or noxious activities, or the benefits realized from their elimination, on real estate prices at more than 40 sites. In support of wise public and private investments in environmental quality, most of these studies aim to inform decision makers about the benefits of remediation and cleanup. Their results vary considerably, but there has been no previous systematic effort to analyze the differences and identify shared insights. This study uses established methods of meta analysis to identify points of agreement and differences in this body of literature. The studies are characterized by the type of site, modeling approach, geographic extent of impacts, data features, and other key factors that underlie their value estimates. The impact estimates are normalized as proportional effects on property values. This study attempts to discover whether the estimated economic impacts of contamination or noxious activity differ according to these characteristics of the studies, and whether anything general can be said about the economic consequences of site contamination and remediation. Bivariate, multivariate, and logit techniques are applied to the data. The results suggest that the property value is the most sensitive to water base contamination, published case studies result in systematically greater environmental value than those in unpublished reports, and real estate markets show responses to environmental condition changes.

  • PDF

Effect of Dunggulle(Polygonatum odoratum) Extracts on Quality of Yakju (둥굴레 엑스첨가가 약주의 품질에 미치는 영향)

  • Lee, Seong-Tae;Kim, Man-Bae;Song, Geon-Woo;Choi, Sang-Uk;Lee, Hong-Jae;Heo, Jong-Soo
    • Food Science and Preservation
    • /
    • v.7 no.3
    • /
    • pp.262-266
    • /
    • 2000
  • The rhizomes of Polygonatum odoratum(Dunggulle in korean name) have been used as a traditional medicine for a tonic, remedy of fevers of influenza, cough and lung trouble. In this experiment, water extract of Dunggulle was added in brewing korean traditional rice wine. Fermentation characteristics such as content of total acid, pH, temperature, total sugar and alcohol concentration were investigated during fermentation periods. Changes of fermentation characteristics were remarkable in the initial period(0~3 days), slow in the middle(4~6 days), and almost unchangeable in the final(7~10 days). Total acid content was remarkably increased during the initial period but slowly decreased afterward. As the content of Dunggulle extract is increased, total sugar content was slightly increased. At the first day of fermentation, total sugar content was 19.6% in control, 22.6, 23.3 and 25.6% in Dunggulle extract 2.5, 5.0 and 7.5% added group, respectively. In the initial period, content of alcohol in control was highest than in Dunggulle extract added group. The content of alcohol in 4 kinds of wine showed highest value at the sixth day and those of control and Dunggulle extract 2.5% were 16.0, 16.1%, respectively. Sensory evaluation in taste was not significantly different among control and Dunggulle extract added group.

  • PDF

Quality of Freeze-Dried Yulmoo-kimchi (동결건조 열무김치의 품질)

  • Ko, Young-Tae;Kang, Jung-Hwa
    • Korean Journal of Food Science and Technology
    • /
    • v.35 no.2
    • /
    • pp.254-259
    • /
    • 2003
  • Effects of freeze-drying on microbiological and sensory characteristics of yulmoo-kimchi (leaf radish kimchi) were investigated. Freeze-dried yulmoo-kimchi was stored at 0, 10 or $25^{\circ}C$ for 60 days and rehydrated with water. Optimum rehydration time of freeze-dried yulmoo-kimchi was 2 hr. Number of lactic acid bacteria of freeze-dried, 10 days-stored, rehydrated yulmoo-kimchi decreased significantly (p<0.05) in comparison with that of reference sample (non-freeze-dried yulmoo-kimchi), while no significant changes were observed after 10 days. As storage temperature increased, number of lactic acid bacteria of 10 days-stored samples decreased. pH value slightly increased by freeze-drying, while it decreased gradually during 60 days of storage. Sensory properties of freeze-dried/rehydrated sample were slightly inferior to those of reference sample, but those were relatively good when the sample was evaluated solely. Overall acceptability of freeze-dried, $0^{\circ}C$-stored, rehydrated sample was significantly inferior to reference sample (p<0.05) and it gradually decreased as storage temperature increased. Between storage periods of 10 through 60 days, sensory properties of 0 and $10^{\circ}C$-stored sample slightly decreased, while those of $25^{\circ}C$-stored sample decreased markedly.

Fermentation Characteristics of Kochujang Prepared with Various Salts (소금의 종류를 달리한 고추장의 발효 특성)

  • Kim, Dong-Han;Yang, Sung-Eun;Rhim, Jong-Whan
    • Korean Journal of Food Science and Technology
    • /
    • v.35 no.4
    • /
    • pp.671-679
    • /
    • 2003
  • Effects of sun-dried, refined, seaweed, and bamboo salts on the quality of kochujang were studied by measuring enzymatic, microbial, and physicochemical characteristics of kochujang during 12 weeks of fermentation. Yeast count was low in the bamboo-salt kochujang, whereas that of aerobic bacteria was low in the seaweed-salt kochujang. Acid protease activity was high in the bamboo-salt kochujang, whereas amylase activity did not show any remarkable difference. Color change was lowest in the bamboo-salt kochujang. Water activities of all kochujangs decreased during fermentation with the lowest shown in the refined-salt kochujang. Consistency of seaweed-salt kochujang was the highest. Total sugar content was higher, whereas ORP was lower in the seaweed- and bamboo-salt kochujangs. Titratable acidity changed slightly in the bamboo-salt kochujang. Reducing sugar content was the lowest, whereas ethanol content was the highest in the refined-salt kochujang. Amino and ammonia nitrogen contents of kochujangs increased up to the middle of fermentation period then decreased with lower changes observed in the sun-dried and refined-salt kochujangs. Results of sensory evaluation indicated that the bamboo-salt kochujang was more acceptable than the sun-dried salt kochujang in taste, color, and overall acceptabilities.

Development of the Waxed Rice Straw Pulp Tray Reduced in Moisture Absorption (흡습억제기능을 보유한 왁스처리 볏짚 트레이의 개발)

  • Ahn, Byoung-Kuk;Park, Sung-Min;Park, Noh-Hyun
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
    • /
    • v.1 no.1
    • /
    • pp.29-37
    • /
    • 1995
  • The purpose of this study was to development the waxed rice straw pulp tray(WRSPT) which had low water sensitivity. The quality changes of mushrooms(Agaricus bisporus) packaged respectively in the WRSPT, non-treated rice straw pulp tray(NRSPT) and expanded polystyrene tray(EPST) were observed during storage. The weight losses of mushrooms in the WRSPTs were less than in the NRSPTs by maintaining below 3% at $0^{\circ}C$ and the applications of WRSPTs were more effective at $20^{\circ}C$. The weight increases of WRSPTs were more lowered than those of NRSPTs by marking below 15% during storage at $0^{\circ}C$. There were no significant differences in the Hunter L values and hardness values of mushrooms in the three types of trays at $0^{\circ}C$. The cap openings of mushrooms were more proceeded in NRSPTs than in WRSPTs and EPSTs at $20^{\circ}C$. As a result, it may be favorable to control excessive moisture absorption of the NRSPT mainly composed of cellulose pulp by introducing such chemical treatments as wax treatment.

  • PDF