• Title/Summary/Keyword: environment condition

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A Preliminary Study on a Restoration of Habitats for Nannophya pygmaea Rambur (Odonata: Libellulidae) (꼬마잠자리(Nannophya pygmaea Rambur: Libellulidae, Odonata) 서식처 복원을 위한 기초연구)

  • Lee, Eun-Heui;Jang, Ha-Kyung;Park, Min-Young;Yoon, Ji-Hyun;Kim, Jae-Geun;Bae, Yeon-Jae
    • Korean Journal of Environment and Ecology
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    • v.22 no.1
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    • pp.35-42
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    • 2008
  • This study was conducted to provide basic information that can be used to restore habitats of Nannophya pygmaea. Nannophya pygmaea is an endangered species of wildlife fauna in Korea and its habitats are distributed very scarcely in Korea. Ten wetland sites throughout Korea, where N. pygmaea inhabited (2 sites in Incheon Muui-do, 1 site in Gokseong Singi-ri, 4 sites in Gokseong Wolbong-ri, and 3 sites in Mungyeong Yulsu-ri) were investigated from June 2006 to August 2007. Investigation was made on landscape properties, habitat sizes, vegetation types, water environments, and water sources. N. pygmaea was generally found in the abandoned paddy fields surrounded by mountains. The habitats ranged from $113.4m^2$ to $1,153.1m^2$ in area, and were mostly dominated by Juncus effusus and Persicaria thunbergii. The water level was $2.6\sim7.3cm$, and the water temperature ranged from $16^{\circ}C$ to $27.8^{\circ}C$. The elevation of the habitats ranged from 139 to 243 m above sea level, which was mostly lower than that of other high mountain wetland habitats. In conclusion, the habitats of N. pygmaea can be restored at wetlands, which have similar condition with field habitat such as abandoned paddy fields in the beginning stage of oligotrophy. Because N. pygmaea is sensitive to microtopography and other surrounding environments, the approach to restore the habitats for N. pygmaea should consider those microhabitat conditions shown in this study.

A Study on Analysis of Variant Factors of Recognition Performance for Lip-reading at Dynamic Environment (동적 환경에서의 립리딩 인식성능저하 요인분석에 대한 연구)

  • 신도성;김진영;이주헌
    • The Journal of the Acoustical Society of Korea
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    • v.21 no.5
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    • pp.471-477
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    • 2002
  • Recently, lip-reading has been studied actively as an auxiliary method of automatic speech recognition(ASR) in noisy environments. However, almost of research results were obtained based on the database constructed in indoor condition. So, we dont know how developed lip-reading algorithms are robust to dynamic variation of image. Currently we have developed a lip-reading system based on image-transform based algorithm. This system recognize 22 words and this word recognizer achieves word recognition of up to 53.54%. In this paper we present how stable the lip-reading system is in environmental variance and what the main variant factors are about dropping off in word-recognition performance. For studying lip-reading robustness we consider spatial valiance (translation, rotation, scaling) and illumination variance. Two kinds of test data are used. One Is the simulated lip image database and the other is real dynamic database captured in car environment. As a result of our experiment, we show that the spatial variance is one of degradations factors of lip reading performance. But the most important factor of degradation is not the spatial variance. The illumination variances make severe reduction of recognition rates as much as 70%. In conclusion, robust lip reading algorithms against illumination variances should be developed for using lip reading as a complementary method of ASR.

Formation and Removal of Trihalomethanes based on Characterization of Hydrophobic and Hydrophilic Precursors (전구물질의 소수성 및 친수성 특성에 따른 트리할로메탄의 생성과 제거에 관한 연구)

  • Jeon, Heekyung;Kim, Junsung;Choi, Yoonchan;Choi, Haeyeon;Chung, Yong
    • Journal of Korean Society on Water Environment
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    • v.24 no.1
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    • pp.123-128
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    • 2008
  • The Dissolved Organic Carbon (DOC) existing in a water includes both hydrophobic and hydrophilic substances however, most of the discussion focuses on hydrophobic substances. The hydrophobic fraction was easily removed by absorption or coagulation more than hydrophilic fraction. Therefore, control of the hydrophilic fraction is very important in water treatment process. This study is to determine the variation of DOC, the removal efficiency of DOC, and Trihalomethane formation potential (THMFP) after each stage of water treatment process by fractionating Natural Organic Matters (NOM) into hydrophobic and hydrophilic substance. DOC from raw water was fractionated at acidic pH (pH<2) using XAD 8 resin column, into two fraction : hydrophobic substance (i.e. humic substance) adsorbed on XAD 8 and hydrophilic substance which represent the organics contained in the final effluent. THMFP was carried out according to the following set condition: Cl2/DOC=4 mg/mg, incubation at $25^{\circ}C$ in darkness, pH 7 adjust with HCl or NaOH as necessary, and 72hour-contact time. THMs analyzed in this study were chloroform, bromodichloromethane, dibromochloromethan, and bromoform. Sewage was almost evenly split between the hydrophobic (56%) and hydrophilic fraction (44%). But, Aldrich humic substance (AHS) was found to contain less hydrophilics (14%) than hydrophobics (86%). The formation of THMs may depend on the source which is characterized by the composition of organic matters such as AHS and sewage. The THMFP yield of sewage and AHS were assessed as follows. The value of the THMFP reaction yield, AHS $172.65{\mu}g/mg$, is much higher than that of sewage $41.68{\mu}g/mg$. This illustrates possible significant difference in THMFP according to the component type and the proportion of organic matter existing in water source. Apparently AHS react with chlorine to produce more THMFP than do the smaller molecules found in sewage. Water treatment process may reduce THMFP, nevertheless residual DOC (the more hydrophilic substance) has significant THMFP. Further reduction in organic halide precursors requires application of alternative treatment techniques.

The Performance of Pollutant Removal Using Nonpoint Treatment Filtration Device and Analysis of the Filter Backwashing Effect (여과형 비점오염 처리장치의 오염물질 제거특성 및 역세척 분석)

  • Lee, Jun-ho;Yang, Seung-ho;Bang, Ki-woong
    • Journal of Korean Society on Water Environment
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    • v.31 no.5
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    • pp.523-532
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    • 2015
  • Hydrocyclone is widely used in industry, for its simple design, high capacity, low maintenance and low operational cost. The objective of this study is to develop hydrocyclone coagulation and filtration system. The system is made of hydrocyclone ballasted coagulation with polyaluminium chloride silicate (PACS) and upflow filter to treat micro particles in urban storm runoff. Roadside sediment particles (< $200{\mu}m$) was mixed with tap water to make various turbid suspensions to simulate urban storm runoff. The filter cartridge was filled with polyethylene media system and ran 1hr per everyday and total operation time were 8.19hrs and backwashing everyday after end of operation. The operation condition of flowrate was $8.2{\sim}11.9m^3/day$ (mean $10.1m^3/day$) and surface overflow rate (SOR) based on filter surface area was $45.5{\sim}65.9m^3/m^2/day$ (mean $55.7m^3/m^2/day$). The range of PACS dosage concentration was 14.0~31.5 mg/L. As the results of operation, the range of removal efficiency of turbidity, SS were 81.0~95.8% (mean 89.5%) 81.8~99.0% (mean 91.4%), respectively. An increase of filtration basin retention time brought on increased of removal efficiency of turbidity and SS, and increase of SOR brought on decreased of removal efficiency. During the first flush in urban area, storm runoff have an high concentration of SS (200~600 mg/L) and the filtration bed becomes clogged and decreased of removal efficiency. Backwashing begins when the drainage pipe valve at the filtration tank bottom is completely open (backwashing stage 1). Backwashing stage 2 was using air bubbles and water jet washing the media for 5 mins and open the drainage valve. After backwashing stage 1, 2, 61.83~64.04%, 18.53~27.51% of SS loading was discharged from filtration tank, respectively. Discharged SS loading from effluent was 7.12~14.79% and the range of residual SS loading in fliter was 2.26~5.00%. The backwashing effects for turbidity, SS were 89.5%, 91.4%, respectively. The hydrocyclone coagulation and filtration with backwashing system, which came out to solve the problems of the costly exchange filter media, and low efficiency of removing micro particles of filter type nonpoint treatment devices, is considered as an alternative system.

A Study on the Applicability of PDA Technique in the P-CAP System for T-P Removal of STP Effluent (하수처리장 방류수의 총인 제거를 위한 P-CAP 시스템에서 PDA 기법의 활용가능성에 대한 연구)

  • Choi, Choongho;Maeng, Sungkyu;Sim, Jaehwi;Choi, Jinho;Song, Kyungguen;Lee, Byungha;Cha, Hoyoung
    • Journal of Korean Society on Water Environment
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    • v.28 no.5
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    • pp.729-742
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    • 2012
  • Recently, to using chemical coagulation process for T-P removal in STP effluent as tertiary treatment process is generalized in the country. The importance of analysis technique to save the treatment & maintenance cost during coagulation process is becoming more increased each day. Thus, it is necessary for the analysis technique during coagulation process to be presented well the characteristic of coagulation in field apply. There are a few analysis techniques such as Jar Test, zeta potential analysis and streaming current detecting techniques. But there are difficult to apply in field immediately due to long test time and difficult analysis techniques. And using PDA technique, it is reviewed applicability of the techniques as field index on pilot plant of P-CAP system The P-CAP system is composed of an in-line static mixer, a Flocculation Tank and the CAP reactor with 2 stage weir for effluent. Pre-test is performed to fix the mixing velocity in the Flocculation Tank using the PDA equipment and it fixed with 30RPM. Also, Jar Test is performed to select optimum dose of each coagulant for each T-P concentration level of influent. Result of continuous test on pilot plant of P-CAP system, the FSI in the Flocculation Tank is increased consistently by increasing each dosing concentration of coagulant such as LAS and PAC in the low level influent T-P concentration comparatively. It is considered that formed Al-hydroxide complexes for dosed coagulant are caused FSI variation. Furthermore, it seems that FSI value in the high level influent T-P concentration appeared lower than the opposite influent condition relatively because it is formed simultaneously Al-hydroxide complexes as solid type and Al-phosphorus complexes as soluble type. Thus, relation of FSI by PDA technique and T-P removal of final effluent on pilot plant of P-CAP system are very limited for the kind of coagulant and the characteristics of influent. And it though that FSI value by PDA technique with analyzing of turbidity in Flocculation Tank will be used restrictedly on field as the relative field-index.

Evaluation of groundwater recharge rate for land uses at Mandae stream watershed using SWAT HRU Mapping module (SWAT HRU Mapping module을 이용한 해안면 만대천 유역의 토지이용별 지하수 함양량 평가)

  • Ryu, Jichul;Choi, Jae Wan;Kang, Hyunwoo;Kum, Donghyuk;Shin, Dong Suk;Lee, Ki Hwan;Jeong, Gyo-Cheol;Lim, Kyoung Jae
    • Journal of Korean Society on Water Environment
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    • v.28 no.5
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    • pp.743-753
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    • 2012
  • The hydrologic models, capable of simulating groundwater recharge for long-term period and effects on it of crops management in the agricultural areas, have been used to compute groundwater recharge in the agricultural fields. Among these models, the Soil and Water Assessment Tool (SWAT) has been widely used because it could interpret hydrologic conditions for the long time considering effects of weather condition, land uses, and soil. However the SWAT model couldn't represent the spatial information of Hydrologic Response Unit (HRU), the SWAT HRU mapping module was developed in 2010. With this capability, it is possible to assume and analyze spatio-temporal groundwater recharge. In this study, groundwater recharge of rate for various crops in the Mandae stream watershed was estimated using SWAT HRU Mapping module, which can simulate spato-temporal recharge rate. As a result of this study, Coefficient of determination ($R^2$) and Nash-Sutcliffe model efficiency (NSE) for flow calibration were 0.80 and 0.72, respectively, and monthly groundwater recharge of Mandae watershed in Haean-myeon was 381.24 mm/year. It was 28% of total precipitation in 2009. Groundwater recharge rate was 73.54 mm/month and 73.58 mm/month for July and August 2009, which is approximately 18 times of groundwater recharge rate for December 2009. The groundwater recharges for each month through the year were varying. The groundwater recharge was smaller in the spring and winter seasons, relatively. So, it is necessary to enforce proper management of groundwater recharge during droughty season. Also, the SWAT HRU Mapping module could show the result of groundwater recharge as a GIS map and analyze spatio-temporal groundwater recharge. So, this method, proposed in this study, would be quite useful to make groundwater management plans at agriculture-dominant watershed.

Evaluation of the Effect of Mine Drainage on the Aquatic Environment by Quantitative Real-time PCR (실시간 정량 중합효소연쇄반응을 이용한 광산 배수의 수계 영향 평가)

  • Han, Ji-Sun;Seo, Jang-Won;Ji, Won-Hyun;Park, Hyun-Sung;Kim, Chang-Gyun
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.2
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    • pp.121-130
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    • 2010
  • Metals and sulfate can be considerably dissolved at low pH condition in the acid mine drainage(AMD) and it would make an environmental problems. There are only few of acid mine drainage treatment systems in Korea which are operating, but these still have an effect on the surrounding stream. In this study, quantification of indicator microorganisms was conducted to judge the environmental impact of AMD on microflora by quantitative real-time PCR in the drainage samples of four mines and the water samples of each surrounding stream. Two species of iron reducing bacteria(Rhodoferax ferrireducens T118 and Acidiphilium cryptum JF-5) were selected for indicator bacteria based on 16S rRNA cloning analysis, and sulfate reducing bacteria(Desulfosporosinus orientus), iron and sulfur oxidizing bacteria(Acidothiobacillus ferrooxidans) and iron oxidizing bacteria(Leptosprillum ferrooxidans) were included into indicator since these were found in the previous studies on the mining area. Thereafter, the comparative analysis of four mines were established by the microbiological variation index and it was determined that the biological environment effect of AMD is highest in Samtan mine which doesn t contain treatment system by the value.

A Proposal for Conservation and Management Policy on Korea's Important Agricultural Heritage (국가중요농업유산의 보전관리를 위한 정책 제안 연구)

  • Beak, Seung-Seok
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.2
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    • pp.98-107
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    • 2017
  • The Ministry of Agriculture, Food and Rural Affairs of Korea(MAFRA) has launched 'The Korea's Important Agricultural Heritage System(KIAHS)' in 2012 to conserve the regional heritages of agriculture and its significance. The effort has achieved in designation of seven KIAHS and two Globally Important Agricultural Heritage System(GIAHS). The policy environment has evolved a great deal since the launch of KIAHS. The study has evaluated the current policy condition of KIAHS and analyzed the shift on the KIAHS policy environment. The study has concluded the policy environmental changes as follows; insufficient Agricultural Heritage(AH) resource development, intensified interests in AH monitoring system, anticipated rural developments thru AH utilizations, under-budgeted AH conservation and management measures. The study has suggested the following based on the evaluation; establishment of AH Conservation and Management System as the conservation and management policy of AH, ease the designation standards for AH, obliged monitoring system for AH, developing AH brand, budget increase for AH conservation and management system. The suggest policy will successfully assist the further development and designation of AH. Farmers in AH area can maintain farm activities thru the conservation, management and utilization of AH, inheriting the important agricultural heritage for the future generation.

A Study on Community-dwelling Elders with Dementia, their Primary Caregiver, and Living Environments (재가 치매노인의 주 수발자와 환경 실태)

  • Kim Nam Cho;Kim Jung Hee;Lim Young Mi
    • Journal of Korean Public Health Nursing
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    • v.16 no.1
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    • pp.13-29
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    • 2002
  • The purpose of this study was to describe about elders with dementia, their families, and their living environment by visiting the households where demented elders resided. The findings will be used as a basis to develop future individualized adjustment programs for demented elders and their families living in communities. The study participants were 64 demented elders and their families who were registered to a dementia counseling center at Nam-Gu community health center located in Inchon, Korea. Data were collected for two months, from May to June 2001. The length of data collection for each home visit ranged from 1.5 to 2.5 hours. Conclusion are as follows based on these study findings: Those demented elders had more than one chronic health problem in addition to their pre-existing dementia condition. Two thirds of the demented elders were not receiving any specific treatment for dementia. They showed a moderate level of independence in basic ADL, but were mostly residing at home because of lack of ability to perform more delicate and complicate routine daily activities by themselves. In addition, the primary caregivers were not well adjusted to the care-giving activities for their demented family members due to the lack of knowledge and information about dementia. The caregivers were mostly women including daughters-in-law, woman spouses and daughters, over a half of whom perceived their physical and mental health status as poor. Their image toward the demented elders was considerably negative. while their level of knowledge on dementia was moderate. The burden for the care-giving was high, whereas their coping method was passive. As the difference in image toward elderly before and after the onset of dementia in their family member increases, the caregiver burden also increased. The main resource of social support for the caregivers was their children. The caregivers showed high level of needs for knowledge and information on dementia, and day care service was the most preferred type of service by the caregivers. There was lack of safety in the living environments for the demented elders and their families, and in the surrounding environments to prevent dementia-related symptoms. Considering that home-based family care-giving is the most culturally appropriate model of providing care for the demented elders in Korea, we need to develop and apply an individualized adjustment program for the demented elders and their families.

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The Characteristic of Fish Community Following the Restoration of Yangjae Stream (복원에 따른 양재천 어류 군집의 특성)

  • Lee, Hwang-Goo;Choi, Jun-Kil
    • Korean Journal of Environment and Ecology
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    • v.29 no.6
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    • pp.873-883
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    • 2015
  • From August 2012 to April 2013, the ichthyofauna and post-restoration properties of Yangjae stream were investigated. A total of 1,503 fish of 2 forms, 16 species and 5 families were studied during the survey period. A survey of the distribution of freshwater fish inhabiting Yangjae stream after restoration of the stream showed large populations of Zacco platypus and Rhynchocypris oxycephalus. From the frequency distribution of the total length for the Zacco platypus population inhabiting Yangjae stream, it was estimated that there are 4 distinct age groups, with an abundance of the 27-63 mm (Age $0^+$) category accounting for 51.3% of the population. The regression coefficient (b) for the length-weight relationship in Zacco platypus was 3.27, while the slope of the condition factor was positive, demonstrating that stable growth conditions are being maintained. Analysis of tolerance and trophic guilds showed a decrease in the numbers of sensitive species and insectivore species further downstream, and an increase in tolerant species and omnivore species. Principal component analysis using community indices and indices of biotic integrity (IBI) showed that there were differences according to the survey time: the first and second surveys showed major changes on certain single species populations while during the third survey, it was analyzed that the populations of various types of fish had established balance.