• Title/Summary/Keyword: Distributed environment

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Performance Evaluation of WWTP Based on Reliability Concept (신뢰성에 기초한 하수처리장 운전효율 평가)

  • Lee, Doo-Jin;Sun, Sang-Woon
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.3
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    • pp.348-356
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    • 2007
  • Statistical and probabilistic method was used in the analysis of data, which is the most effective one in describing the various natures, and the methodology relating the results with the design was developed. Influents and effluents of three treatment plants were analyzed and the focus was made on BOD, COD, SS, IN, TP The fluctuations of influent such as BOD, COD, SS were extremely large and their standard deviations(st.dev) were more than 10 mg/L. but those of TN, TP were small; the st.dev was 6.6 mg/L for TN, 0.6 mg/L for TP, respectively. But, effluent concentration showed consistent pattern regardless of the influent fluctuations, the st.dev was ranged between 0.28 and 4.48 mg/L. Effluent distributional characteristics were as follows; BOD, COD were distributed normally, but SS, TN, and TP, log-normally; unsymmetric and skewed to the right. The coefficient of reliability(COR) based on the results of statistics of data was introduced to evaluate the process performance an4 to reflect the process performance to the process design. The coefficient of reliability relates the design value(the goal) with the standards and it can be used in operating treatment facilities under a certain reliability level and/or in evaluating the reliability of the treatment facilities on operation. Each treated water quality of effluent showed the half of water quality standards in the level of 50% percentile and all treatment plant was achieved 100% probability of water quality standards. It was concluded that the variability of the process performance should be reflected to the design procedure and the standards through the analysis based on the statistics and the probability.

Enhancement and Quenching Effects of Photoluminescence in Si Nanocrystals Embedded in Silicon Dioxide by Phosphorus Doping (인의 도핑으로 인한 실리콘산화물 속 실리콘나노입자의 광-발광현상 증진 및 억제)

  • Kim Joonkon;Woo H. J.;Choi H. W.;Kim G. D.;Hong W.
    • Journal of the Korean Vacuum Society
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    • v.14 no.2
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    • pp.78-83
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    • 2005
  • Nanometric crystalline silicon (no-Si) embedded in dielectric medium has been paid attention as an efficient light emitting center for more than a decade. In nc-Si, excitonic electron-hole pairs are considered to attribute to radiative recombination. However the surface defects surrounding no-Si is one of non-radiative decay paths competing with the radiative band edge transition, ultimately which makes the emission efficiency of no-Si very poor. In order to passivate those defects - dangling bonds in the $Si:SiO_2$ interface, hydrogen is usually utilized. The luminescence yield from no-Si is dramatically enhanced by defect termination. However due to relatively high mobility of hydrogen in a matrix, hydrogen-terminated no-Si may no longer sustain the enhancement effect on subsequent thermal processes. Therefore instead of easily reversible hydrogen, phosphorus was introduced by ion implantation, expecting to have the same enhancement effect and to be more resistive against succeeding thermal treatments. Samples were Prepared by 400 keV Si implantation with doses of $1\times10^{17}\;Si/cm^2$ and by multi-energy Phosphorus implantation to make relatively uniform phosphorus concentration in the region where implanted Si ions are distributed. Crystalline silicon was precipitated by annealing at $1,100^{\circ}C$ for 2 hours in Ar environment and subsequent annealing were performed for an hour in Ar at a few temperature stages up to $1,000^{\circ}C$ to show improved thermal resistance. Experimental data such as enhancement effect of PL yield, decay time, peak shift for the phosphorus implanted nc-Si are shown, and the possible mechanisms are discussed as well.

A Study on the Family Strength and the Career Maturity of High School Students (고등학생의 가족건강성과 진로성숙도에 관한 연구)

  • Yang, Nam-Hee;Hong, Eun-Sil
    • Journal of Korean Home Economics Education Association
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    • v.23 no.4
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    • pp.143-157
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    • 2011
  • This study aims to identify family strength and career maturity, and to explore the difference of career maturity according to family strength, targeting high school students as subjects. A total of 1,000 copies of the questionnaire were distributed and 858 copies were used for the final analysis. The major results are summarized as follows: In respect to general tendency of family strength and career maturity, the score of family respect was the highest, 3.59, followed by 3.56 of gratitude and affection, 3.54 of problem shooting ability, economic stability, faithfulness to role, emotional bond, positive communication and goal sharing. The score of emotional bond with society was the lowest, 2.90. The score of family strength was 3.36, which was the intermediate level. As sub-factors of career maturity, the score of relevancy was 3.40, and that of tendency was 3.17, followed by that of independence and compromise. The score of determination was the lowest, 2,75. A total score of career maturity was 3.05. Family strength was marked highly by the girls students studying humanities, and religious ones. Those whose parents have high education and no-divorce background also showed high scores. High school students with higher economic levels and long-married parents showed higher scores than high school students with poor economy levels and single parents. Students with parents who have professional jobs also marked high scores. Career maturity degree as a background variable was significantly higher in the following cases: In terms of religious background, students whose mother are buddhists or atheists marked high scores. High scores were marked by those whose parents have higher education and no-divorce background. High school students from middle class and over and long-married parents showed higher career maturity degree than high school students with poor economy levels and single parents. Students with parents who have professional jobs also marked high career maturity degree. While career maturity degree, which is subjected to family strength, showed very different results when analysed with 5 sub-variables. As family strength resulted in positive effects to career maturity degree, higher family strength showed higher career maturity degree. Especially, in the areas of relevance and tendency of career maturity degree, the effects of positiveness was clearly high.

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Vascular Plants Distributed in the Iris koreana of Gaeamsa Temple and Soeppulbawi Rock Areas in Special Protection Zones of Byeonsanbando National Park (변산반도국립공원 특별보호구인 개암사 및 쇠뿔바위 지역의 노랑붓꽃 자생지에 분포하는 식물상)

  • Oh, Hyunkyung
    • Journal of Environmental Impact Assessment
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    • v.26 no.5
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    • pp.365-375
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    • 2017
  • This study investigated in the vascular plants of special protection zones (the native land of Iris koreana in Gaeamsa Temple and Soeppulbawi Rock) of Byeonsanbando National Park and identified the whole flora. The numbers of vascular plants were summarized as 255 taxa including 71 families, 166 genera, 222 species, 2 subspecies, 27 varieties and 4 forms. Woody plants were identified as 114 taxa (44.7%) and herbaceous plants as 141 taxa (55.3%). A total of 178 taxa were identified in the area of Gaeamsa Temple, and 184 taxa were found in the Soeppulbawi Rock. As a legal protected species, the endangered wild plant II grade Iris koreana designated by the Ministry of Environment was confirmed. A total of 6 taxa of rare plants were identified, each of which was divided into 1 taxa of critically endangered (CR; Iris koreana), 1 taxa of vulnerable (VU; Ilex cornuta), and 4 taxa of least concern (LC; Asarum maculatum, Viola albida, Chionanthus retusa and Tricyrtis macropoda). The Korean endemic plants were 11 taxa (Populus tomentiglandulosa, Lonicera subsessilis, Carex okamotoi, etc.). In the specific plants by floristic region were 38 taxa, a degree I were 23 taxa (Euscaphis japonica, Hedera rhombea, Lophatherum gracile, etc.), 7 taxa of a degree II (Viola violacea, Ainsliaea apiculata, Cephalanthera falcata, etc.), 6 taxa of a degree III (Ilex cornuta, Callicarpa mollis, Mitchella undulata, etc.), 1 taxa of a degree IV (Carex remotiuscula), 1 taxa of a degree V (Iris koreana). The Iris koreana special protection area that is more natural and healthier than any other areas in Byeonsanbando National Park. Therefore, it should be possible to continue its role as a special protection area through regular monitoring in the future.

Geological Characteristics of Extra Heavy Oil Reservoirs in Venezuela (베네주엘라 초중질유 저류층 지질 특성)

  • Kim, Dae-Suk;Kwon, Yi-Kyun;Chang, Chan-Dong
    • Economic and Environmental Geology
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    • v.44 no.1
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    • pp.83-94
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    • 2011
  • Extra heavy oil reservoirs are distributed over the world but most of them is deposited in the northern part of the Orinoco River in Venezuela, in the area of 5,500 $km^2$, This region, which has been commonly called "the Orinoco Oil Belt", contains estimated 1.3 trillion barrels of original oil-in-place and 250 billion barrels of established reserves. The Venezuela extra heavy oil has an API gravity of less than 10 degree and in situ viscosity of 5,000 cP at reservoir condition. Although the presence of extra heavy oil in the Orinoco Oil Belt has been initially reported in the 1930's, the commercial development using in situ cold production started in the 1990's. The Orinoco heavy oil deposits are clustered into 4 development areas, Boyaco, Junin, Ayachoco, and Carabobo respectively, and they are subdivided into totally 31 production blocks. Nowadays, PDVSA (Petr$\'{o}$leos de Venzuela, S.A.) makes a development of each production block with the international oil companies from more than 20 countries forming a international joint-venture company. The Eastern Venezuela Basin, the Orinoco Oil Belt is included in, is one of the major oil-bearing sedimentary basins in Venezuela and is first formed as a passive margin basin by the Jurassic tectonic plate motion. The major source rock of heavy oil is the late Cretaceous calcareous shale in the central Eastern Venezuela Basin. Hydrocarbon materials migrated an average of 150 km up dip to the southern margin of the basin. During the migration, lighter fractions in the hydrocarbon were removed by biodegradation and the oil changed into heavy and/or extra heavy oil. Miocene Oficina Formation, the main extra heavy oil reservoir, is the unconsolidated sand and shale alternation formed in fluvial-estuarine environment and also has irregularly a large number of the Cenozoic faults induced by basin subsidence and tectonics. Because Oficina Formation has not only complex lithology distribution but also irregular geology structure, geological evolution and characteristics of the reservoirs have to be determined for economical production well design and effective oil recovery. This study introduces geological formation and evolution of the Venezuela extra heavy oil reservoirs and suggest their significant geological characteristics which are (1) thickness and geometry of reservoir pay sands, (2) continuity and thickness of mud beds, (3) geometry of faults, (4) depth and geothermal character of reservoir, (5) in-situ stress field of reservoir, and (6) chemical composition of extra heavy oil. Newly developed exploration techniques, such as 3-D seismic survey and LWD (logging while drilling), can be expected as powerful methods to recognize the geological reservoir characteristics in the Orinoco Oil Belt.

Spatial Distribution of Soft Bottom Macrobenthos of Yeoja Bay in Summer Season, South Coast of Korea (여자만 연성저질의 여름철 대형저서동물 공간분포)

  • Lim, Hyun-Sig
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.20 no.2
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    • pp.78-91
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    • 2015
  • Macrobenthic community was studied at 87 stations including intertidal and subtidal area in Yoja Bay, south coast of Korea in summer season of July 2001. Duplicate sediment samples were taken using a van Veen grab ($0.1m^2$) in each station. Mud facies of the sediments were widly distributed in the bay. And relatively high content of sand was shown in the Bulgyo-cheon stream estuary. A total of 274 species was occurred with a mean density of $2,346ind./m^2$ and a mean biomass of $78.2g/m^2$. The polychaetes were species- and density-dominant faunal group with a total of 122 species (44.5% of the total number of species), and mean density of $1,543ind./m^2$ (65.8% of the mean density). Meanwhile, molluscs were biomass-dominant faunal group with $44.4g/m^2$. Bio-Env. analysis showed that the combination of bottom salinity and sand content of the surface sediments was highly correlated to the major macrobenthic communities. The macrobenthic species number, decreasing toward inner bay from mouth of the bay, was significantly correlated to the sediment environmental variables and bottom water salinity. The spatial distribution of abundance showed significant correlation to the sand and mud contents and mean grain size of the surface sediments. Major dominant species were Minuspio japonica (polychaete) with a mean density of $1,167ind./m^2$ at upper part of the bay where salinity was low and Eriopisella sechellensis (amphipod) with $152ind./m^2$ in central part of the bay. Species diversity (H') was $3.0{\leq}$ in the mouth part of the bay and ranged 2.0-3.0 in the inner part of the bay, which showed a significant positive correlation to bottom salinity. Total number of species also showed significant correlations to the sediment composition and bottom salinity. Based on the cluster analysis the macrobenthic community of the bay was classified into five station groups from the bay mouth toward the inner part of the bay depending on the species composition. From the SIMPER analysis Minuspio japonica, Eriopisella sechellensis and Sternaspis scutata mainly contributed to the classification of station group. These results suggested that the macrobenthic communities of the bay were mainly influenced by bottom salinity together with sediment composition, and that the studies of spatial distributions of major dominant species and benthic communities should be conducted continuously to monitor the Yeoja Bay benthic environment.

Occurrence and Cenesis of Perlite from the Beomgockri Group in Janggi Area (장기지역 범곡리층군에 부존되는 진주암의 산출상태와 생성관계)

  • Noh Jin Hwan;Hong Jin-Sung
    • Journal of the Mineralogical Society of Korea
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    • v.18 no.4 s.46
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    • pp.277-288
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    • 2005
  • Perlite, a hydrated volcanic glass, occurs mainly as a bed-like body, and is distributed intermittently along the unconformity surface between the Beomgockri Group and its lower formations, viz. Janggi Group. The perlite is intimately associated with surrounding pumiceous welded tuff and rhyodacites in space and time. Compared to the typical perlite, the perlite is rather silica-poor and impure, and thus, includes lots of phenocrysts and rock fragments. Nearly the perlite is compositionally rather close to a pitchstone than a perlite in water contents. Petrographic comparison between perlite and associated volcanic to volcaniclastic rocks indicates that pumiceous welded tuff and rhyodacite seem to be Protolith of the Perlite. A Zr/$TiO_{2}$-Nb/Y diagram and field occurrence of perlite and their protolithic rocks also conforms the above interpretation. Kn addition, remnant vesicles in perlite strongly reflect that the precursor of perlitic glass appeared to be pumice fragment as well as volcanic glass. The perlite was diagenetically formed by way of a pervasive water-rock interaction at the deposition of the Manghaesan Formation in lacustrine environment. During perlitization, $SiO_{2}$ and alkali tend to be consistently depleted. Preexisting system of the Beomgockri Group based on the perlite formation should be corrected, because the perlite was formed diagenetically without lateral persistence in its occurrence.

Development and Application of a Methodologyfor Climate Change Vulnerability Assessment-Sea Level Rise Impact ona Coastal City (기후변화 취약성 평가 방법론의 개발 및 적용 해수면 상승을 중심으로)

  • Yoo, Ga-Young;Park, Sung-Woo;Chung, Dong-Ki;Kang, Ho-Jeong;Hwang, Jin-Hwan
    • Journal of Environmental Policy
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    • v.9 no.2
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    • pp.185-205
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    • 2010
  • Climate change vulnerability assessment based on local conditions is a prerequisite for establishment of climate change adaptation policies. While some studies have developed a methodology for vulnerability assessment at the national level using statistical data, few attempts, whether domestic or overseas, have been made to develop methods for local vulnerability assessments that are easily applicable to a single city. Accordingly, the objective of this study was to develop a conceptual framework for climate change vulnerability, and then develop a general methodology for assessment at the regional level applied to a single coastal city, Mokpo, in Jeolla province, Korea. We followed the conceptual framework of climate change vulnerability proposed by the IPCC (1996) which consists of "climate exposure," "systemic sensitivity," and "systemic adaptive capacity." "Climate exposure" was designated as sea level rises of 1, 2, 3, 4, and 5 meter(s), allowing for a simple scenario for sea level rises. Should more complex forecasts of sea level rises be required later, the methodology developed herein can be easily scaled and transferred to other projects. Mokpo was chosen as a seaside city on the southwest coast of Korea, where all cities have experienced rising sea levels. Mokpo has experienced the largest sea level increases of all, and is a region where abnormal high tide events have become a significant threat; especially subsequent to the construction of an estuary dam and breakwaters. Sensitivity to sea level rises was measured by the percentage of flooded area for each administrative region within Mokpo evaluated via simulations using GIS techniques. Population density, particularly that of senior citizens, was also factored in. Adaptive capacity was considered from both the "hardware" and "software" aspects. "Hardware" adaptive capacity was incorporated by considering the presence (or lack thereof) of breakwaters and seawalls, as well as their height. "Software" adaptive capacity was measured using a survey method. The survey questionnaire included economic status, awareness of climate change impact and adaptation, governance, and policy, and was distributed to 75 governmental officials working for Mokpo. Vulnerability to sea level rises was assessed by subtracting adaptive capacity from the sensitivity index. Application of the methodology to Mokpo indicated vulnerability was high for seven out of 20 administrative districts. The results of our methodology provides significant policy implications for the development of climate change adaptation policy as follows: 1) regions with high priority for climate change adaptation measures can be selected through a correlation diagram between vulnerabilities and records of previous flood damage, and 2) after review of existing short, mid, and long-term plans or projects in high priority areas, appropriate adaptation measures can be taken as per this study. Future studies should focus on expanding analysis of climate change exposure from sea level rises to other adverse climate related events, including heat waves, torrential rain, and drought etc.

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Geochemical Characteristics of the Uljin Granitoids in Northeastern Part of the Yeongnam Massif, Korea (영남육괴 북동부 울진지역 화강암류의 지화학적 특성)

  • Wee, SooMeen;Kim, Ji-Young;Lim, Sung-Man
    • Journal of the Korean earth science society
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    • v.34 no.4
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    • pp.313-328
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    • 2013
  • Jurassic granitoids in the northeastern part of the Yeongnam Massif are possibly the result of intensive magmatic activities that occurred in response to subduction of the proto-Pacific plate beneath the northeast portion of the Eurasian plate. Geochemical studies on the granitic rocks are carried out in order to constrain the petrogenesis of the granitic magma and to establish the paleotectonic environment of the area. Whole rock chemical data of the Uljin granitoids in the northeastern part of the Yeongnam Massif indicate that all of the rocks have the characteristics of calcalkaline series in subalkaline field. The overall major element trends show systematic variations in each granitic body, but the source materials of each granitoids seem to have different chemical composition. The Uljin granitoids are different from other granitic rocks, which distributed vicinity of the study area, in the contents of $Al_2O_3$ and trace elements such as Cr, Co, Ni, Sr, Y and Nb. The Uljin granitoids have geochemical features similar to slab-derived adakites such as high $Al_2O_3$, Sr contents and high Sr/Y, La/Yb ratios, but they have low Y and Yb contents. The major ($SiO_2$, $Al_2O_3$, MgO) and trace element (Sr, Y, La, Yb) contents of the Uljin granitoids fall well within the adakitic field. The Uljin granitoids have similar geochemical characteristics, paleotectonic environments and intrusion ages to those of the Yatsuo plutonic rocks of Hida belt located on northwestern part of Japan. Chondrite normalized REE patterns show generally enriched LREEs ($(La/Yb)_{CN}=10.6-103.4$) and are slight negative to flat Eu anomalies. On the ANK vs. A/CNK and tectonic discrimination diagrams, parental magma type of the granites corresponds to I-type and volcanic arc granite (VAG). Interpretations of the chemical characteristics of the granitic rocks favor their emplacement in a compressional tectonic regime at the continental margin during the subduction of Izanagi plate in Jurassic period.

Effects of Dietary Addition of Wormwood (Artemisia sp.) on the Growth Performance, Nutrients Utilization, and Abdominal Fat Deposition of Broiler Chickens (사료내 쑥 첨가가 육계의 성장률, 영양소 이용률, 복강내 지방에 미치는 영향)

  • Lee, Sung-Jin;Song, Ki-Duk;Ko, Yung-Du;Kim, Chang-Hyun
    • Korean Journal of Organic Agriculture
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    • v.18 no.3
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    • pp.347-361
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    • 2010
  • This study was carried out to investigate the effects of wormwood (Artemisia sp.) addition on the growth performance, nutrients utilization and abdominal fat deposition of broiler chickens. Two hundred twenty five and two-day old Arboracre strain male commercial broiler chicks were distributed to 5 treatments with wormwood supplementation levels; C(O%), $T_1$ (1%), $T_2$ (3%), $T_3$ (5%), and $T_4$ (10%) and with 3 replications each with 5 birds for five weeks. Body weight gain during the experiment was improved in $T_1$ (1723.0g) compared with that of $T_3$ (1557.7g) and $T_4$ (1450.7g) (P<0.05). Feed intake was significantly (P<0.05) increased as the levels of wormwood addition increased (C: 2653.8g, T1: 2852.0, $T_2$: 2900.3, $T_3$: 2900.7g, T4: 2954.7g). Feed conversion rate (feed/gain) was significantly (P<0.05) increased as the levels of wormwood addition increased (C: 1.55, $T_1$: 1.66, $T_2$: 1.70, $T_3$: 1.86, $T_4$: 2.04). The days reaching to 2.0kg of body weight were expected to be 43.2 days in control, whereas those of group T1 were reduced to 42.6 days by 0.6 day from control. Nutrient utilization and abdominal fat deposition in the experiment were significantly decreased (P<0.05) and small intestine contents in the broilers was significantly increased (P<0.05) as the levels of wormwood addition increased. Therefore, although there was no significant improvement for the performance of broiler chickens with the dietary supplementation of wormwood meal, less than 1% addition of wormwood to broiler diets might have beneficial for human health by reducing the abdominal fat deposition of the broiler chicknens.