• 제목/요약/키워드: P2P Control

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Corrosion Control in Water Distribution System using Lime and Carbon Dioxide(I) - Determination of Optimum Operational Conditions in Lime Adding Process (소석회와 CO2를 이용한 상수관로의 부식제어(I) - 소석회 주입공정의 최적 운전인자 도출)

  • Sohn, Byung-Young;Byun, Kyu-Sik;Kim, Young-Il;Lee, Doo-Jin
    • Journal of Korean Society of Water and Wastewater
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    • v.22 no.3
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    • pp.373-378
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    • 2008
  • The pH & alkalinity adjustment method by lime and carbon dioxide($CO_2$) for corrosion control in water distribution system was investigated to determine the optimum operational condition in lime adding process in water treatment plant(WTP). The mixing time at dissolution tank and sedimentation time at saturator for maintaining optimal turbidity condition of lime supernatant were 60~75 minutes and 75~95 minutes, respectively. There was no difference according to $CO_2$ adding methods such as $CO_2$ saturated water or $CO_2$ gas. But, $CO_2$ saturated water could be convenience at WTP in terms of pH control and quantitative dosing. To minimize generation of calcium carbonate products, the short time interval between adding of lime and $CO_2$ is most important. The lime should be added below 32 mg/l for preventing pH rising and generation of calcium carbonate products at the heating condition.

A Study on the metabolism mechanism of Benzene, Toluene and Xylene by Cytochrome P-450 dependent radical-mediated (Cytochrome P-450 의존성 radical 전달에 의한 Benzene, Toluene, Xylene의 대사기전 연구)

  • 김기웅;장성근;김양호;문영한
    • Toxicological Research
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    • v.11 no.2
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    • pp.205-213
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    • 1995
  • This study was undertaken to investigate the effects of organic solvents on xenobiotic metabollzing enzyme system in vivo by meaas of experimental conditions i.e. (1) single group which was treated by benzene (B), toluene (T) and xylene (X), respectively, (2) combination group which was treated by mixture of benzene+toluene (BT), benzene+xylene (BX), and toluene+xylene (TX), respectively, (3) mixture group which was treated by benzene+ toluene+xylene mixture (M), and to interpreat the interaction between the organic solvents metabolizing enzymes. 1. The contents of cytochrome P-450 in liver microsomes were increased (p < 0.01) in organic solvents treated groups, and the contents of cytochrome P-450 were increased by following order of B < T < M < BT=BX < X < TX. 2. The activity of cytochrome P-450 dependent AHHase was significantly higher in organic solvents treated groups than in control group (p < 0.01), and the activity of AHHase was increased by following order of B < T < BT=BX=TX=xylene < M. 3. The activity of NADPH P-450 reductase was significantly higher in organic solvents treated groups than in control group (p < 0.01), and the order of M < combinated group < X < T

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Effect of Infection Control Knowledge and Nursing Work Environment on Infection Control Performance among General Hospital Nurses (종합병원 간호사의 감염관리지식, 간호근무환경이 감염관리수행도에 미치는 영향)

  • Choi, Kyunga;Moon, Mikyung
    • Journal of muscle and joint health
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    • v.30 no.2
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    • pp.120-128
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    • 2023
  • Purpose: The purpose of the study was to investigate the effects of infection control knowledge and nursing work environment on infection control performance among general hospital nurses. Methods: A total of 138 nurses from four general hospitals located in G and P cities participated in this descriptive study. The collected data were analyzed using t-test, ANOVA, Pearson's correlation coefficients, and multiple regression. Results: The average mean score was 21.41±1.92 points out of 25 for infection control knowledge, 2.53±0.33 points out of 4 for nursing work environment, and 4.62±0.40 points out of 5 for infection control performance. In the final analysis, the variables that had the greatest influence on infection control performance were the nursing work environment (β=.32, p<.001), working department (β=.19, p=.014), and knowledge (β=.19, p=.016). Conclusion: This study showed that nurses with a better nursing work environment, employment in general department, and more infection control knowledge delivered superior infection control performance. Therefore, to improve infection control performance, it is necessary to enhance the nursing environment and develop practical education programs for augmenting infection control knowledge.

Estimation of the Optimum Factor of the Struvite Crystalization for the Nitrogen and Phosphorus Removal in WWTP (폐수내 질소 및 인 제거를 위한 struvite 결정화 최적조건 도출)

  • Kim, Ji Yeon;Moon, Yong Taik;Seo, In Seok;Kim, Byung Goon
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.6
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    • pp.745-753
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    • 2007
  • By struvite and hydroxyapatite crystallization, was high concentration of nitrogen and phosphorus in wastewater simultaneously. Particularly, removal of nitrogen and phosphate for crystallization have been applied to landfill leachates and animal wastewater. The purpose of this study is to decide the optimum struvite crystallization factors, sequence of $Mg^{2+}$ addition, pH control and the molar ratio of $Mg^{2+}$ over $PO_4^{3-}$. In conclusion, dosage of the magnesium followed by pH control formed magnesium hydroxide, so pH was decreased. Therefore, pH adjustment should followed by after magnesium dosage and then pH should be adjusted to 11. Over pH 10, it was not good for struvite crystallization efficiency by side reaction. Following of the $Mg^{2+}$ and the $PO_4^{3-}$ are dosed excessively, the removal efficiency of the $NH_4^+$ increased. A molar ratio of $Mg^{2+}:NH_4^+:PO_4^{3-}$, 1.3:1:1.3 was the most on effective for $NH_4^+$ removal at pH 9.5. But for the perfect removal $NH_4^+$, it is thought to be that molar ratio should be 2:1:2.

Effects of the Self-managed Seogeum Therapy among College Students with Allergic Rhinitis (서금요법 자가관리 프로그램이 대학생의 알레르기비염에 미치는 효과)

  • Park, Hong Ju;Kim, Nam Hee
    • Journal of East-West Nursing Research
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    • v.25 no.2
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    • pp.103-116
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    • 2019
  • Purpose: This study investigated the effects of the Seogeum therapy among college students with allergic rhinitis. Method: A non-equivalent control group pretest-posttest non-synchronized design was used. Intervention of Seogeum therapy has been performed from March 2 through March 31, 2017. Sixty college students diagnosed with allergic rhinitis from two different colleges in B and K cities were assigned to the experimental and control group. Data analysis were conducted using descriptive statistics, chi-square test, Fisher's exact test, and t-test. Results: There were significant differences in nose itching (t=4.89, p<.001), sneezing (t=6.26, p<.001), watery rhinorrhea (t= 4.09, p<.001), nasal congestion (t=2.36, p=.022), the percent of eosinophil (t=2.01, p=.049), perceived stress (t=2.05, p=.045), and allergic rhinitis related quality of life (t=4.33, p<.001) between the two groups. However, there were no significant differences in the percent of IgE (t=0.60, p=.553) and level of cortisol (t=0.53, p=.598). Conclusion: The results of this study indicates that the self-management of Seogeum therapy improved physical and psychological status of the college students with allergic rhinitis which ultimately improved their quality of life.

Effects of Yijin-tang (Erchen-tang) and GamiYijin-tang (Jiaweierchen-tang) on the Gastrointestinal Functions of Rats (이진탕 및 가미이진탕이 흰쥐의 위장관기능에 미치는 영향에 대한 연구)

  • 옥명정;변준석;박순달;이학인
    • The Journal of Korean Medicine
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    • v.23 no.3
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    • pp.11-25
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    • 2002
  • Objectives: This study was undertaken to investigate the effects of Yijin-tang and GamiYijin-tang on the gastrointestinal functions of rats Methods: Sprague-Dawley rats were used as experimental animals, and were administered Yijin-tang (Sample I group, 47.5 mg/ml) and GamiYijin-tang(Sample II group, 38.37 mg/ml, Sample ill group, 85.3 mg/ml) water extract once a day. Changes of gastric juice volume and intestinal mobility index were measured. The effects on colitis induced by dextran sulfate sodium in the rats were also observed. Results: 1. Gastric juice volume was decreased significantly in the sample I group (P<0.05) compared to the control group; there was not significant effect in the sample II and sample III groups. 2. The moving distance of carbon bolus was increased significantly in the sample n (p<0.05) and sample II (p<0.05) groups compared to the control group; there was not significant effect in the sample I group. 3. The intestinal mobility index was increased significantly only in the sample II group (P<0.05) compared to the control group. 4. The feces consistency was increased significantly on the 3rd and 5th day of the sample I group (P<0.05), on 3rd, 4th, and 5th day of the sample II (p<0.05) and the sample III (p<0.05) groups compared to the control group. 5. The feces property index was increased significantly only on the 5th day of the sample III group (p<0.05) compared to the control group. 6. The number of WBC and RBC, levels of hemoglobin and hematocrit were not changed in all sample groups compared to the control group. 7. The number of the type B Goblet cells were increased significantly in the sample II (p<0.05) and the sample III (P<0.05) groups, but the number of the type C Goblet cells were decreased significantly only in the sample ill group (P<0.05) compared to the control group. Conclusions: According to the above results, GamiYijin-tang compared to the Yijin-tang were decreased hight significantly in gastrointestinal mucose and histological antidiarrheal function with protection of the goblet cell more excellently were observed.

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Effect of Calcium Lactate Prepared from Black Snail on Dough Fermentation, Quality and Shelf-life of Bread (다슬기로 제조한 칼슘 락테이트가 반죽의 발효와 빵의 품질 및 저장성에 미치는 영향)

  • 이예경;이명예;김순동
    • Journal of the East Asian Society of Dietary Life
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    • v.13 no.2
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    • pp.136-144
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    • 2003
  • This study was conducted to investigate the effect of 0.5% calcium lactate(CaL) on the fermentation of dough and quality and shelf-life of bread. Calcium lactates(CaL-A and CaL-P) were prepared from ash of black snail which contained shell and tissue together(ABS) and powder of the snail(PSB). pH of dough with the CaLs were higher than that of the control md, volume of the dough, loaf volume of bread were lower than those of the control products. But the volumes were almost the same when the pH of the dough were adjusted to pH 5.5. Mean calcium contents of treated bread (39.36~49.70 mg/100 g) were higher than that of control products(13.43 mg/100 g). There was no difference in Hunter $L^{*}$, $a^{*}$, $b^{*}$ values between the control and the treated group. Hardness and gumminess of CaL-A treated bread were the highest, but springiness and cohesiveness were the lowest. All the attributes showed no difference in case of pH adjustment(pH 5.5). The smaller pore and larger air cell with rough surface were observed in the CaL treated bread by SEM analysis. Sensory scores of CaL treated bread showed relatively lower values than those of the control products, but the scores increased by pH adjustment. The shelf-life of bread with CaL-P and CaL-A at 2$0^{\circ}C$ were 4 and 3 days, respectively, while that of the control group 1 day.day.y.

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Evaluation of Extended Canine Semen by Glass Wool filtration (Glass Wool Filtration을 이용한 개 희석정액의 운동성과 생존률의 검정)

  • Yoon Jae-Won;Lee Young-Jun;Kim Sue-Hee;Ji Dong-Beom;Kim Yong-Jun
    • Journal of Veterinary Clinics
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    • v.22 no.3
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    • pp.228-232
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    • 2005
  • Damaged spermatozoa are supposed to be trapped in glass wool. In the respect of this, two glass wool filtration spermatozoa groups (0.5 cm, 1 cm depth) were compared with control group to assay sperm motility, HOS values, and vital rate by CFDA/PI staining method following glass wool filtration. The motility of canine sperm extended with PBS+PVP after glass wool filtration was lower in both filtrated groups than that of the control group (p<0.01) and the same significant difference was also shown in canine semen extended with Tris buffer (p<0.01). The motility of canine sperm diluted with PBS+PVP was higher than that diluted with Tris buffer in the same experimental groups (p<0.05). The motility of control group was not significantly decreased until 2 hours immediately after extending, however, the motility of both glass wool filtrated spermatozoa were significantly decreased as time passed until 2 hours after filtration (p<0.01). At each time for assay (immediately, 30 min, 2 hours after filtration), the motility of canine sperm of control group was higher than the filtrated groups (p<0.05), whereas the motility of 0.5 cm depth group was higher than 1 cm depth group at the immediate time after filtration (p<0.05), 30 minutes later (p<0.05) with no difference at 2 hours. No difference was shown among the experimental groups in HOS values of canine sperm after glass wool filtration. The vital rate assayed by CFDA/PI staining of both filter groups was higher than the control group (p<0.05).

High-Efficiency a-Si:H Solar Cell Using In-Situ Plasma Treatment

  • Han, Seung Hee;Moon, Sun-Woo;Kim, Kyunghun;Kim, Sung Min;Jang, Jinhyeok;Lee, Seungmin;Kim, Jungsu
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.230-230
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    • 2013
  • In amorphous or microcrystalline thin-film silicon solar cells, p-i-n structure is used instead of p/n junction structure as in wafer-based Si solar cells. Hence, these p-i-n structured solar cells inevitably consist of many interfaces and the cell efficiency critically depends on the effective control of these interfaces. In this study, in-situ plasma treatment process of the interfaces was developed to improve the efficiency of a-Si:H solar cell. The p-i-n cell was deposited using a single-chamber VHF-PECVD system, which was driven by a pulsed-RF generator at 80 MHz. In order to solve the cross-contamination problem of p-i layer, high RF power was applied without supplying SiH4 gas after p-layer deposition, which effectively cleaned B contamination inside chamber wall from p-layer deposition. In addition to the p-i interface control, various interface control techniques such as thin layer of TiO2 deposition to prevent H2 plasma reduction of FTO layer, multiple applications of thin i-layer deposition and H2 plasma treatment, H2 plasma treatment of i-layer prior to n-layer deposition, etc. were developed. In order to reduce the reflection at the air-glass interface, anti-reflective SiO2 coating was also adopted. The initial solar cell efficiency over 11% could be achieved for test cell area of 0.2 $cm^2$.

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Growth, Carbon and Nitrogen Status of Container Grown Black Pine (Pinus thunbergii) Seedlings at Various Levels of Foliar Fertilization

  • Kim, Choonsig;Jeong, Jaeyeob;Moon, Tae-Shik;Park, Jun-Ho;Lim, Jong-Taek;Kim, Jong-Ik;Goo, Gwan-Hyo
    • Journal of Korean Society of Forest Science
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    • v.98 no.5
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    • pp.558-562
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    • 2009
  • The growth, carbon and nitrogen status of container grown black pine (Pinus thunbergii) seedlings were examined at various levels of foliar fertilization (control, 0.1%, 0.2%, 0.3%). Root collar diameter, height and dry weight of black pine seedlings increased significantly with increasing levels of foliar fertilization (P<0.05). Carbon concentration in needle of black pine seedlings was significantly higher in the foliar fertilization than in the control treatments (P<0.05), while other seedling components such as stem and roots were not significantly different (P>0.05) between the foliar fertilization and the control treatments. Nitrogen concentration and content were significantly greater in the foliar fertilization than in the control treatments (P<0.05). Shoot/root ratio of black pine seedlings (needle+stem dry weight/root dry weight) was greater in the foliar fertilization (2.40-2.89) than in the control treatments (1.87). However, nitrogen use efficiency was significantly lower (P<0.05) in the foliar fertilization (28-46) than in the control (111) treatments. The results indicate that morphological characteristics and nutritional status on container grown black pine seedlings were enhanced by various levels of foliar fertilization.