• Title/Summary/Keyword: Black-out time

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Bionomics, Host range & Analysis of Damage Aspects on the Black Pine Bast Scale, Matsucocus thunbergianae (Homoptera : Cocoidea), in the Coastal Area of Southwest Korea (한국 남서해안지대의 해송림에 만연된 솔껍질깍지벌레(Matsucocus thunbergianae)의 생태, 기주범위 및 피해해석에 관한 연구(I))

  • 김규진;오광인
    • Korean journal of applied entomology
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    • v.31 no.4
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    • pp.386-395
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    • 1992
  • The black pine bast scale, Matsucoccus thunbergianae, causes severe damage to the black pines of southern coastal areas. It has one generation a year, coming out of the pine bark to mate a and lay eggs from early March to early May. Especially, its peak time is from late March to m mid-April. The host plants were found to be 7 species, Pinus thunbergii, P. strobus, P. taeda, P. b banksiana, P. massoniana, P. taiwannesis, and P. densiflora. The percentage of damaged black p pine by the age were 0.8% for I-year old ones, 3.7% for 4-6 years, 5.2% for 7-9 years, 9.3% f for 10-12 years, 8.1% for 13-15 years, 7.8% for 16-18 years, 6.7% for 19-21 years, 3.3% for 2 22-24 years, 1.9% for 25-27 years, and 1.1 % for 28 years. The highest rate of damage happened to 7 -20 years old trees, whereas the highest rate of damage upon branches happened to 6 6-7 years old ones. Finally, as far as the trunk is concerned, the damages proceeded from the m middle parts of the trunk, whose branches were alive up to the top. The rates of damage s spread in pure forest/mixed forest area were turned out to be 81.3/52.5% in Koheung, 80.3/ 5 58.1 % in Haenam, and 76.3/48.5% in Muan. That is, the damage rate was higher in the pure f forest areas than the mixed forest ones. The higher the density of trees beyond 20 trees per m 100$m^2$, the higher the damage rate was.

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Cases Study of Accidents in High Risk Organizations by System Dynamics (시스템 다이내믹스 기법을 활용한 고위험 조직 사고 사례 분석)

  • Oh, Youngmin;Ryu, Jin
    • Korean System Dynamics Review
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    • v.16 no.3
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    • pp.5-29
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    • 2015
  • The importance of the concept of safety culture has increased in the security of high-risk facility after Chernobyl accident in 1986. This paper elaborated the concept of safety culture and its main factors by Causal Loop Diagram. Due to the decline of safety culture, the occurrence of incidents and accidents require more and more corrective actions to the members of high-risk facilities and thereby increasing their workloads. Employees who must complete the task within the given time have to have time pressures and don't comply with the rules and procedures. Also, a schedule pressure is a big stress for employees, causing mistakes in precision work. In order to improve these problems, CLD of the safety culture in this paper suggests hiring more workers, re-allocation of given workloads and strengthen the learning, communication capabilities and safety leadership. In addition, the two real accident cases were analyzed to test the feasibility of the System Dynamic simulation model through the process of structuring the fault trees on the stationary black out accident in Kori unit 1 in South Korea and Kleen Energy power station explosion in US. The simulation results show that the various safety factors cause the serious accident combined with mechanical failure and safety culture will reduce the possibility of the accidents in these high-risk organizations. This simulation model can contribute to analyzing the impact of the organizational and human factors of safety culture and can provide the alternatives in high-risk facilities.

Rewriting Race in Hopkins's Of One Blood; Or, the Hidden Self: "the Hidden Self," Past/Memory, Incest, and Black Female Body (홉킨스의 인종 다시쓰기-"숨겨진 자아,"과거/기억, 근친상간, 그리고 흑인여성의 몸)

  • Kang, Hee
    • Journal of English Language & Literature
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    • v.54 no.2
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    • pp.301-322
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    • 2008
  • Pauline Hopkins's Of One Blood; Or, the Hidden Self was published in the Colored American Magazine during 1902-03. As a literary experimentalist and a political protester, Hopkins uses her fiction as a medium to overcome and ameliorate the violently racialized surroundings of the turn-of-the-century America. Having been faced with racist rhetorics and theories growing on biological differences between races, Hopkins must have felt an overwhelming urgency to challenge the heritage of slavery in American history. In order to speak out her political agenda in such a milieu, she needed a new setting as well as new narrative materials for the new era. She had to move the setting from America to Africa, the ancient utopian Ethiopia; her interest in the ancient African civilization reflects both a popular African-American vision of Africa and the movement of "black nationalism" of the time. She also needed materials from nineteenthcentury sciences, the newly evolving theories of psychology and mysticism (spiritualism/mesmerism), to explore the meaning of "the hidden self" which unfolds the complex nature of Hopkin's position on race, "blood," and African-American racial subjectivity. Hopkins in the novel explores not the color line but the bloodline. Tracing the horrific legacy of incest in the history of slavery, she attempts to redefine the true racial identity of African-Americans in America and to reconstruct their past, both family and race history. At the very center of her major tropes in the novel-such as "of one blood," "the hidden self," and incest-exists female body. Black female body, though it represents the violent site of sexual body (rape and incest) in slavery, ultimately becomes a vehicle to convey and preserve the truth of racial memory/past/history for African-Americans. As a conveyor of the past, black women not just connect the past and the present but also reawaken AfricanAmericans with the legacy of the African 'pure' bloodline. Hopkins's vision here necessitates the reevaluation of black women's role in family and history, heralding the 20th-century black feminine writing. With the major tropes, Hopkins clearly suggests that the blood of (African-)Americans is unrecognizably intermixed. Although the novel ends with ambivalence and without resolution on what Africa signifies, those tropes certainly offer her a vehicle for criticizing as well as for challenging the racial reality of America.

Effects of Aged Black Garlic Extracts on the Rheology of Flour Dough (숙성 흑마늘 추출액 첨가가 빵용 밀가루 반죽의 레올로지 특성에 미치는 영향)

  • Wang, Sug-Ja;Lee, Jeong-Hoon;Choi, Mi-Jung;Lee, Si-Kyung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.3
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    • pp.430-435
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    • 2012
  • This study was carried out to investigate the rheological effects of black garlic extracts on the bread dough. 0, 5, 10 and 15% of black garlic extracts were added in the bread flour. Falling number, RVA (Rapid visco analyser), farinograph and alveograph were analyzed. Falling number was lowered by increasing the amount of the extract added in the wheat flour. The pasting characteristics of the dough by RVA, value of pasting temperature, peak viscosity, holding strength, final viscosity, break down and set back were increased compared to the control. In the Farinograph analysis, the consistency and the water absorption ratio were elevated with the increase of the extract added. However, the rapid decrease of stability and the time to breakdown values were observed by increasing the extract addition amount compared to the control. However the mixing tolerance index (MTI) was rapidly increased as the amount of the extract addition was increased, and the highest farinogram quality number was observed in the control. Through the alveograph analysis, $P_{max}$ value was found to show the highest value in the control, while the L and G values were higher but W values was lowered in the dough with added 15% black garlic extract. As a result of the analysis, there was no significant bad effect until 5% of black garlic extracts was added to the bread dough.

The analysis study of mural painting pigments at Pongjongsa Kuknakjon (봉정사 극락전 벽화 안료의 재질 분석 연구(II))

  • Cho, Nam-Chu;Hong, Jong-Ouk;Moon, Whan-Suk;Hwang, Jin-Ju
    • 보존과학연구
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    • s.21
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    • pp.119-143
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    • 2000
  • The pigments composition and structure of the mural painting at Pongjongsa Kuknakjon is discussed. The structure of inner wall is consisited of Paint layer, Ground divided two layers of yellow and white pigments, Support. In case of outer wall, it is consisted of Paint layer, Ground divided three layers of yellow and green pigments, a layer mixed green pigments and paint layer, Support. As a result of compositon analysis of mural painting pigments at Pongjongsa Kuknakjon using Micro-area X-ray diffraction system, the red pigment on inner wall is consisted of Heamatite($Fe_2O_3$), Magnetite($Fe_3O_4$)of deep black pigment, and Chalcocite($Cu_2S$) of light black pigment. The white pigment on outer wall is consisted of Anglesite($PbSO_4$) and Atacamite($Cu_2CI(OH)_3$) of green pigment. We found out that natural pigments painted in the mural painting at Pongjongsa Kuknakjon has kept up its own color for a long time due to using the natural pigment not to artificial synthetic pigment.

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Denitrification of Anaerobic Sludge in Hybrid Type Anaerobic Reactor(II): Glucose as Substrate (Hybrid type 반응조에서의 혐기성 슬러지의 탈질(II): 기질이 글루코스인 경우)

  • Shin, Hang-Sik;Kim, Ku-Yong;Lee, Chae-Young
    • Journal of Korean Society of Water and Wastewater
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    • v.14 no.2
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    • pp.196-206
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    • 2000
  • Methanogenesis and denitrification in an upflow sludge baffled filter (UBF) reactor were studied using glucose as a fermentative substrate. Experiments were carried out to investigate how to reduce ammonification by changing alkalinity and $COD/NO_3-N$ ratio. Characteristics of granular sludges were examined by specifics methanogenic activity(SMA) and specific denitrification rate(SDR) tests. Microstructures of granules were examined using a scanning electron microscopy(SEM). It was found that COD was removed efficiently owing to the diverse microorganisms. In nitrate conversion, not only $COD/NO_3-N$ ratio but also influent alkalinity played important role in the ratio of denitrification and ammonification of nitrate. This reactor achieved over 95% COD and 99% nitrate removal efficiencies when influent contained 4000 mgCOD/L and $700mgNO_3-N/L$ at the hydraulic retention time of 24 hours. As $COD/NO_3-N$ ratio decreased, granular methanogenic activities using acetate and butyrate as substrates increased while activities using propionate and glucose decreased. There were three types in granules according to the surface color; gray, yellowish gray, and black. Gray or yellowish gray-colored granules were composed two layers, which were composed of black inner side and gray or yellowish gray surface substances. SEM illustrated that both were rod-type and cocci-type microorganisms resembling Methanothrix sp. and Methanococci sp. This study showed that by controlling the influent alkalinity and $COD/NO_3-N$ ratio, ammonification and denitrification could be manipulated.

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Changes in Growth and Yield of Peucedanum japonicum Thunberg by Planting Time, Mulching, and Planting Density (식방풍(植防風)의 파종기(播種期), 피복(被覆), 재식밀도(栽植密度)에 따른 생육(生育)과 수양(收量) 변화(變化))

  • Chung, Sang-Hwan;Kim, Ki-Jae;Suh, Dong-Hwan;Lee, Kwang-Seok;Choi, Boo-Sull
    • Korean Journal of Medicinal Crop Science
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    • v.2 no.2
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    • pp.121-126
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    • 1994
  • This experiment was carried out in the field to investigate the effects of sowing time, mulching materials and planting density on the growth and root yield of Peucedanum japonicum. The optfimum planting time for yield increase at Kyungbuk area whether the plant was grown under non-mulching or black P. E. mulching condition. Black polyethylene (P. E) film mulching was effective to promote emergence and growth, and dry root yield in the P. E. mulching was 10% higher than that in the non-mulching condition. The yield in the $20{\times}15cm$ planting density was 50% higher than that in the conventional $30{\times}20cm$.

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COMPARATIVE STUDY ON THE DETECTION OF PORPHYROMONAS ENDODONTALIS BY ANAEROBIC CULTURE, IIF AND DNA PROBE METHOD IN INFECTED ROOT CANALS (감염 근관에서 혐기성 배양법과 간접 면역 형광법 및 DNA 프로브법에 의한 Porphyromonas endodontalis의 검출에 관한 비교 연구)

  • Kim, Min-Kyum;Yoon, Soo-Han;Chung, Chong-Pyoung
    • Restorative Dentistry and Endodontics
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    • v.21 no.1
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    • pp.1-18
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    • 1996
  • There are many advantages when using IIF and DNA probe methods over anaerobic culture method in that they are time-and effort-saving, more precise and more sensitive. Furthermore, in IIF and DNA probe methods, the detection is possible only with small amount of bacteria, the quantitative analysis is possible, and the cell viability is not necessary. The purpose of this study is to observe the incidence of P.endodontalis by carrying out anaerobic culture, IIF and colony lift using DNA probe method respectively, and to compare these 3 methods in terms of effectiveness and sensitivity in order to identify the most effective detection method. 30 teeth with at least one clinical symptoms, with single canal, and with pulp necrosis were sampled. For sampling bacteria, access cavity was prepared after disinfecting tooth and its surroundings. Then the paper point was inserted up to the periapical area, leave there for a while, and finally it was placed into PRAS Ringer's sol. and PBS sol. In anaerobic culture method, P.endodontalis was identified by biochemical tests after subculturing black and brown colonies which were produced after 7 days of incubation on BAP and Brucella BAP in anaerobic chamber. To identify P.endodontalis in IIF method, species-specific polyclonal rabbit-antisera of P.endodontalis(ATCC 35406) was reacted with sampled PBS sol. dispensed onto glass slide, and then P.endodontalis was examined by phase contrast microscopy after incubating with Goat anti-rabbit lgG conjugated to Fluorescein isothiocyanate. For colony lift using DNA probe method, membranes were laid over colonies on the surface of BAP and were hybridized with cloned DNA probe of P.endodontalis. The existence of P.endodontalis was then identified by the methods of chemiluminescent detection and color metric detection. Black colony was found in 11 teeth out of 30 teeth and P.endodontalis was detected in 6 teeth (20 %) by anaerobic culture method, 16 teeth (53 %) by IIF method, and 7 teeth (23 %) by DNA probe method. IIF method is significantly better in detecting P.endodontalis than DNA probe method and anaerobic culture method. There was no significant differences between DNA probe method and anaerobic culture method. There was significant correlation between the formation of black colony and the existence of P.endodontalis. The probability of detecting P.endodontalis when black colony being present is 2.89 times higher than when not being present. There was significant relationship between the foul odor of clinical symptoms and P.endodontalis. The sensitivity of existing P.endodontalis when foul odor being present was 93.75 %, while the specificity of not existing P.endodontalis when foul odor not being present was 28.57 %. These results suggested that the probes of P.endodontalis will be used to decide the method and prognosis in endodontic treatments.

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Statistical Process Control System for Continuous Flow Processes Using the Kalman Filter and Neural Network′s Modeling (칼만 필터와 뉴럴 네트워크 모델링을 이용한 연속생산공정의 통계적 공정관리 시스템)

  • 권상혁;김광섭;왕지남
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.3
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    • pp.50-60
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    • 1998
  • This paper is concerned with the design of two residual control charts for real-time monitoring of the continuous flow processes. Two different control charts are designed under the situation that observations are correlated each other. Kalman-Filter based model estimation is employed when the process model is known. A black-box approach, based on Back-Propagation Neural Network, is also applied for the design of control chart when there is no prior information of process model. Performance of the designed control charts and traditional control charts is evaluated. Average run length(ARL) is adopted as a criterion for comparison. Experimental results show that the designed control chart using the Neural Network's modeling has shorter ARL than that of the other control charts when process mean is shifted. This means that the designed control chart detects the out-of-control state of the process faster than the others. The designed control chart using the Kalman-Filter based model estimation also has better performance than traditional control chart when process is out-of-control state.

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Effect of Surface Ozone on Vegetation in Korea - Preliminary Study on Early Foliage of Robinia pseudo-acacia - (한국의 지면 오존이 식생에 미치는 영향에 관한 연구 - 아까시나무 조기낙엽 현상과 관련성 검토 예비 연구 -)

  • Cho, Seog-Yeon
    • Journal of Korean Society for Atmospheric Environment
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    • v.23 no.1
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    • pp.29-38
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    • 2007
  • Recently, the tropospheric ozone has gained a global attention for its adverse effect on vegetation as well as its contribution to the global warming. Although a number of studies have been carried out for the urban ozone, the effect of ozone on vegetation is still largely unknown in Korea. The present work aimed at performing the first evaluation of forest damage by ozone using the national air monitoring data from the year 2000 to the year 2005. Moreover, it also explored the relevance of adverse effect of ozone to the recent events on leaf chlorosis of black locust, Robinia pseudo-acacia, leading to early foliage widely observed in Korea since 2001. In the nineties, forest damages caused by ozone such as leaf chlorosis occurred in Europe and North America and led to invoke comprehensive field and laboratory studies. As a result, AOT40, implying the accumulated dose over a threshold 40 ppb, was developed to assess the forest damage by ozone. 19 air monitoring stations were selected across Korea to calculate AOT40 from the year 2000 to the year 2005. The calculated AOT40 generally increased during April and May and reached the maximum after May. The increase of AOT40 diminished substantially from the mid-June as the rainy season started. The calculated AOT40 in the nine rural sites from the year 2002 to th ε year 2005 ranged from 6.8 to 29.4 ppm-hr. And all the AOT40 at th ε year 2005 exceeded the critical value of 10 ppm-hr for forest damage. Morevoer the calculated AOT40 of Korea appeared higher than the AOT40 of Europe in the year 2004/2005 and comparable to the AOT40 of China in the year 2000. Despite the high levels of the calculated AOT40 since the year 2001 and the consistency of time of seasons between high AOT40 values and occurrence of chlorosis of black locust, further studies are required to conclude that the chlorosis of black locust occurred from the year 2001 to the year 2005 were resulted from a damage by ozone.