• 제목/요약/키워드: controlling factor

검색결과 954건 처리시간 0.031초

Effects of DO concentration on Simultaneous Nitrification and Denitrification(SND) in a Membrane Bioreactor(MBR) (MBR 단일 반응조에서 용존산소 농도에 따른 동시 질산화-탈질반응(SND)의 영향)

  • Park, Noh-Back;Choi, Woo-Yung;Yoon, Ae-Hwa;Jun, Hang-Bae
    • Korean Journal of Environmental Agriculture
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    • 제28권4호
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    • pp.371-377
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    • 2009
  • In this study, simultaneous nitrification and denitrification (SND) from synthetic wastewater were performed to evaluate dissolved oxygen(DO) effects on chemical oxygen demand(COD) and nitrogen removal in a single membarne bio-reactor(MBR). DO levels in MBR at Run 1, 2, and 3 were 1.9~2.2, 1.3~1.6, and 0.7~1.0 mg/L, respectively. Experimental results indicated that DO had an important factor to affect COD and total nitrogen(TN) removal. SND were able to be accomplished in the continuous-aeration MBR by controlling ambient DO concentration. It is postulated that, because of the oxygen diffusion limitation, an anoxic micro-zone was formed inside the flocs where the denitrification might occur. From the results of this study, 96% of COD could be removed at DO of 0.7mg/L. At run 2 72.92% of nitrogen was removed by the mechanisms of SND (7.75mg-TN/L in effluent). In this study, SND was successfully occurred in a MBR due to high MLSS that could help to form anoxic zone inside microbial floc at bulk DO concentrations of 1.3~1.6mg/L.

A Study on the Spatial Configuration and Characteristics of Visitors' Movement in Science Museum(I) (과학계 박물관의 전시공간구성과 관람객 움직임의 특성(I))

  • Lim, Che-Zinn;Choo, Sung-Won;Park, Moo-Ho
    • Korean Institute of Interior Design Journal
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    • 제20권3호
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    • pp.206-214
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    • 2011
  • The premise of this study is that an ultimate objective in planning an exhibition space is visitors' experiences created by a result of their first-hand experiences and responses within an exhibition space, and this result can be recognized in the visitors' movement. Thus, the exhibition layout that can directly affects viewers' main line of flow and movement patterns was examined vis--vis a mutually complementary relation in a triangular composition with the structure of exhibition space and the exhibition contents. This study, with the subjects of standing exhibit halls of Gwacheon National Science Museum, Daejeon National Science Museum, and Tokyo National Museum of Emerging Science and Innovation, analyzed 'the correlation between the configuration of the exhibition area and the visitors' movement. The targeted subjects were analyzed from the perspectives of type of architectural space and organization of the exhibition method, and the purpose of this study was to find a spatial evidence to predict the spectator movement formed within the exhibition halls of science museums. The main indicators used are: Based on the investigation/analysis as described above, the following conclusion could be drawn. Diversity of exhibition environment and spectator movement: besides the two big categories of the types of architectural space and types of exhibition method, the construction of vertical circulation and size and shape of the exhibition space, distribution characteristics of exhibition medium, organization of symbolic space and such other diverse organizations and combinations of exhibition environment are implied to have the capability to alter the scope and degree of predicting spectator movement. As an example, the types of architectural space comprising the wide-area viewing circulation was found to be able to change the system of planar circulation according to the composition of vertical circulation. Along with this, it was implied that the format of architectural space influences the form of the exhibition space, and may also act as a factor directly influencing the diversity and arrangement of the exhibition methods. That is, the spatial elements comprising the exhibition environment acts inter-complexly, and exhibits characteristics of limiting or controlling spectator movement.

Risk factors of type 2 diabetes among Korean adults: The 2001 Korean national health and nutrition examination survey

  • Chung, Hae-Rang;Perez-Escamilla, Rafael
    • Nutrition Research and Practice
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    • 제3권4호
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    • pp.286-294
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    • 2009
  • This study aimed to identify risk factors for type 2 diabetes (T2D) in Korea, a rapidly changing country. Data of 5,132 adults aged 20-85 were used from the 2001 Korean Health and Nutrition Examination Survey. Multiple logistic regression was carried out to identify risk factors for T2D. Three models were specified: (i) socioeconomic and demographic factors (model 1: age, gender, education, poverty income ratio, employment), (ii) behavioral risk factors and covariates (model 2: obesity, physical activity, smoking, alcohol drinking, dietary quality, family history of T2D, co-morbidity) and (iii) socioeconomic, demographic, and behavioral factors (model 3). The prevalence of T2D was 7.4%. Less education (OR 1.41, 95% CI 1.08-1.84), age (OR 2.19, 95% CI 1.56-3.08 in 40-59 yrs, OR 4.05, 95% CI 2.76-5.95 in 60 yrs + comparing to 20-39 yrs) and abdominal obesity (OR 2.24, 95% CI 1.79-2.82) were risk factors for T2D even after controlling for other factors simultaneously. There was a significant association of T2D with ever smoking (OR 1.34, 95% CI 1.06-1.67). The relationship of age with T2D was modified by gender in model 1 and the relationship of smoking with T2D was modified by obesity in model 2. Less educated, older, obese or ever smokers were more likely to have T2D. Gender mediated the relationship of age, and obesity mediated the relationship of smoking, with T2D. Intervention programs for T2D in Korea should take the interactions among risk factors into account.

Kalopanaxsaponin A Exerts Anti-Inflammatory Effects in Lipopolysaccharide-Stimulated Microglia via Inhibition of JNK and NF-κB/AP-1 Pathways

  • Jeong, Yeon-Hui;Hyun, Jin-Won;Le, Tien Kim Van;Kim, Dong-Hyun;Kim, Hee-Sun
    • Biomolecules & Therapeutics
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    • 제21권5호
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    • pp.332-337
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    • 2013
  • Microglial activation plays an important role in the development and progression of various neurological disorders such as cerebral ischemia, multiple sclerosis, and Alzheimer's disease. Thus, controlling microglial activation can serve as a promising therapeutic strategy for such brain diseases. In the present study, we showed that kalopanaxsaponin A, a triterpenoid saponin isolated from Kalopanax pictus, inhibited inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and tumor necrosis factor (TNF)-${\alpha}$ expression in lipopolysaccharide (LPS)-stimulated microglia, while kalopanaxsaponin A increased anti-inflammatory cytokine interleukin (IL)-10 expression. Subsequent mechanistic studies revealed that kalopanaxsaponin A inhibited LPS-induced DNA binding activities of NF-${\kappa}B$ and AP-1, and the phosphorylation of JNK without affecting other MAP kinases. Furthermore, kalopanaxsaponin A inhibited the intracellular ROS production with upregulation of anti-inflammatory hemeoxygenase-1 (HO-1) expression. Based on the previous reports that JNK pathway is largely involved in iNOS and proinflammatory cytokine gene expression via modulating NF-${\kappa}B$/AP-1 and ROS, our data collectively suggest that inhibition of JNK pathway plays a key role in anti-inflammatory effects of kalopanaxsaponin A in LPS-stimulated microglia.

Cauldron Subsidence and Ore Mineralization in the Southeastern kyongsang basin: A review (경상분지 남동부 광상의 분포와 콘트론과의 관계 : 재검토)

  • Yun, Sung-Hyo;Yang, Kyoung-Hee
    • Economic and Environmental Geology
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    • 제32권3호
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    • pp.217-225
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    • 1999
  • Nine cauldrons have been recognized in the PVD (Pusan- Taegu Volcano-tectonic Depression) zone covering an area of nearly 7,000 $km^{2}$. They form characteristic landscape features with various mountains in the southeastern Kyongsang basin. Economically important ore deposits are also developed either in the ring fracture zone or the central pluton within the resurgent cauldrons or in the marginal area of the PVD, suggesting that these cauldrons played a major role in the distribution of ore deposits in the southeastern Kyongsang basin. Furthermore, the cauldron subsidences were more frequent with the more felsic volcano-plutonic complex, possibly indicating that the amounts of water and volatile components also acted as a controlling factor to cause the caldera subsidence and to concentrate the ore-forming elements in economic concentrations. The review of the relationship and variations of ore mineralization and cauldron subsidence is rather sketchy, but it provides a skeleton to carry out more detailed and quantitative studies related to temporal and spatial relationships between each cauldron subsidence accompanying its own ore mineralization. In the southeastern Kyongsang basin, additional calderas and associated ore deposits undoubtedly can be discovered through future detailed studies. The concept that cauldron subsidence are an important control for the formation of ore deposits will appear to be vindicated.

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Understanding of Resilience and Its Application through Small Group Activities in Christian Universities (자아탄력성의 이해와 기독교대학에서의 소그룹 활동을 통한 적용)

  • Bong, Won Young
    • The Journal of the Korea Contents Association
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    • 제14권3호
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    • pp.509-521
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    • 2014
  • The purpose of this study is to find the correlation between elements of resilience and small group activities in the university, and to explore small group activities as a protective and a positive factor in controlling the stress of college students. As the first part of the study, positive roles of resilience to the stress of college students and the elements that promote the efficiency of resilience are analyzed. The study precedent in detail and four elements of resilience are presented as following; optimistic realism, vitality, ability to control emotion, and interpersonal ability, addressing the faith in God is one of the strong positive factors for developing resilience. Then, this study deals with how the four elements of resilience relates to the characteristics of small group activities. In conclusion, this study suggests Christian universities to develop small group activities because they can develop each of the four elements of resilience of college students. Christian universities have a missional duty and the responsibility to help college students experience real happiness in their lives. Therefore, if Christian universities understand the effectiveness of resilience of college students and find out the correlation between resilience and faith, they can help students not only to live a positive life in their generation, but also to experience the authentic happiness.

Influencing Factor on the Attitudes toward Elders among Nurses Working at Geriatric Hospitals: Focusing on Empathy (노인병원 간호사의 노인에 대한 태도에 영향을 미치는 요인: 공감을 중심으로)

  • Kim, Jung-Hee;Jeong, Hye-Sun
    • The Journal of the Korea Contents Association
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    • 제13권12호
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    • pp.840-850
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    • 2013
  • This study examined influencing factors on the attitudes toward elders with a focus on empathy. Data were gathered from 291 nurses working at 14 geriatric hospitals in Kyunggi-Do, Chungchung-Do and Incheon. In analyzing the data, Pearson correlation coefficients, t-test, ANOVA, and regression analysis were adopted. Attitudes toward elders were neutral on the average; those nurses revealed both positive and negative aspects such as friendly, good, kind, conservative, sick and dependent. Of the four empathy scales, only empathic concern revealed significant correlation with the attitudes toward elders. Regression model included empathic concern and the nurses' characteristics. Empathic concern was significant in predicting the attitudes toward elders after controlling for the effects of the nurses' characteristics. Experience of voluntary work for elders was the only predictor among individual characteristics. Explanatory power of the model was 10.7%. We need to develop intervention programs raising empathy among nurses. The instrument measuring empathy needs to be examined.

Synthesis of Flake Ag Powder by Polyol Process (폴리올법에 의한 편상의 은 분말 합성)

  • Kim Dong-Jin;Liang Huanzhen;Ahn Jong-Gwan;Lee Jae-Ryeong;Chung Hun-Saeng
    • Journal of Powder Materials
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    • 제11권6호
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    • pp.477-485
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    • 2004
  • Monodispersed flaky silver powder was obtained by controlling the ratios of $H_{2}O_{2}/NH_{3}$ and Agin in a mixed solution of ethylene glycol and ammonia with an addition of PVP. The effects of $NH_{3}/Ag,\; H_{2}O_{2}/Ag\;and\;H_{2}PtCl_{6}/Ag$ on its morphology and size were investigated. In $H_{2}O_{2}-NH_{3}-AgNO_{3}\;system,\;NH_{3}/Ag$ molar ratio was found to be an important reaction factor for the nucleation and crystal growth of Ag powder. The synthesis of flaky powder was optimized at over 6 of $NH_{3}/Ag \;and\;5\;of\;H_{2}O_{2}/Ag\;under\;1.0{\times}10^{-3}\;of\;Pt/Ag.\;Moreover,\;as\;the\; NH_{3}/Ag$ molar ratio increased, the size of precipitates was increased regardless of the amount of Pt. In the absence of $H_{2}PtCI$, the morphology and size of reduced Ag powder were found to be irregular in shape $2-4{\mu}m$ in diameter. However, homogenized fine Ag powder was obtained due to heterogeneous nucleation when $H_{2}PtCI$ used as a cat-alyst, and flaky one was synthesized with the addition of Pt over $1.0{\times}10^{-3}$ of Pt/Ag.

Preliminary Study on Human Sensibility Evaluation of Ringtone in Mobile Phone (휴대폰의 벨소리 감성만족도 평가를 위한 예비연구)

  • Kweon, O-Seong;Choi, Jae-Hyun
    • Science of Emotion and Sensibility
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    • 제12권4호
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    • pp.403-410
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    • 2009
  • The purpose of this study was to find whether there is sound quality difference among mobile service providers in terms of ringtone in mobile phones, and identify factors that contribute to the difference of sound quality. A series of experiments were performed to identify the source of sound difference while controlling brand factor of the leading company. Mobile service provider, phone manufacturer, phone model variation, specific music genre and contents provider factors were examined. The results showed there was sound quality difference among mobile service providers. The difference comes from mobile phones provided to service provider and sound contents. There was difference in sound quality among same models that provided to different service providers. The different sound making process contributed to the difference of sound quality. The genre effect was not clear. To complement the limitation of samples used, an interview with the sound expert of mobile device was performed. The results showed hardware parts used and careful tuning of the device can influence to the sound quality of the mobile phone.

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Significance of nm23, Bcl2 and Bax Expression in Papillary Thyroid Carcinoma (유두상 갑상선암에서 nm23, Bcl2, Bax 발현도의 임상적 의의)

  • Chung Woung-Youn;Lee Hae-Kyung;Baik So-Ya;Park Cheong-Soo
    • Korean Journal of Head & Neck Oncology
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    • 제16권2호
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    • pp.161-166
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    • 2000
  • Objective: The nm23 gene has been identified as a potential metastasis suppressor gene in various human neoplasms. Both Bcl-2, which promotes cell survival, and Bax, which promotes cell death, have been considered as major factors in controlling the apoptotic pathway. This study was carried out to determine whether these markers are useful in distinguishing potential intrinsic differences in tumor virulence of papillary thyroid cancers. Material and Method: The expressions of nm23, Bcl-2 and Bax have been evaluated using immunohistochemical techniques in 100 pure papillary thyroid cancers and 20 metastatic lymphnodes. The intensity of immnunoreactivity was graded on arbitrary four point scale(grade 0 or 1 : negative reactivity, grade 2 or 3 positive reactivity). The immunoreactivities were analyzed in relation to TNM atage, AMES score, local recurrence and distant metastasis, and that of metastatic LNs was compared with the tumors. Results: The expression of Bcl-2 and bax did not show any statistical differences by TNM stage, AMES score, recurrence, distant metastasis and also between the tumor and metastatic LN. However, the nm23 showed higher expression of Ki67 in distant metastasis than in control group and in metastatic LNs than in the tumors(p<0.05). Conclusion: Although the expression of Bcl-2 and Bax protein showed no correlation with clinical parameters representing tumor virulence, the nm23 expression could be an useful prognostic factor, especially in predicting nodal or distant metastasis in papillary thyroid cancer.

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