• Title/Summary/Keyword: Reference method

Search Result 6,893, Processing Time 0.039 seconds

Biological Toxicity Assessment of Sediment at an Ocean Dumping Site in Korea (폐기물 배출해역 퇴적물의 생물학적 독성평가 연구)

  • Seok, Hyeong Ju;Kim, Young Ryun;Kim, Tae Won;Hwang, Choul-Hee;Son, Min Ho;Choi, Ki-young;Kim, Chang-joon
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.28 no.1
    • /
    • pp.1-9
    • /
    • 2022
  • The effect of sediments in a waste dumping area on marine organisms was evaluated using sediment toxicity tests with a benthic amphipod (Monocorophium acherusicum) and bioluminescent bacterium (Vibrio fischeri) in accordance with the Korean Standard Method for Marine Wastes (KSMMW). Nine sites in the East Sea-Byeong, East Sea-Jeong, and Yellow Sea-Byeong areas were sampled from 2016 to 2019. The test results showed that the relative average survival rate (benthic amphipods) and relative luminescence inhibition rate (luminescent bacteria) were below 30%, which were judged to be "non-toxic." However, in the t-test, a total of 12 benthic amphipod samples (6, 1, 1, and 4 in 2016, 2017, 2018, and 2019, respectively) were significantly different (p<0.05) from the control samples. To identify the source of toxicity on benthic amphipods, a simple linear regression analysis was performed between the levels of eight heavy metals (Cr, As, Ni, Cd, Cu, Pb, Zn, and Hg) in sediments and the relative average survival rate. The results indicated that Cr had the highest contribution to the toxicity of benthic amphipods (p = 0.000, R2 = 0.355). In addition, Cr was detected at the highest concentration at the DB-85 station and exceeded the Marine Environment Standards every year. Although the sediments were determined as "not toxic" according to the ecotoxicity criteria of the KSMMW, the results of the statistical significance tests and toxicity identification evaluation indicated that the toxic effect was not acceptable. Therefore, revising the criteria for determining the toxic effect by deriving a reference value through quantitative risk assessment using species sensitivity distribution curves is necessary in the future.

Geomagnetic Paleosecular Variation in the Korean Peninsula during the First Six Centuries (기원후 600년간 한반도 지구 자기장 고영년변화)

  • Park, Jong kyu;Park, Yong-Hee
    • The Journal of Engineering Geology
    • /
    • v.32 no.4
    • /
    • pp.611-625
    • /
    • 2022
  • One of the applications of geomagnetic paleo-secular variation (PSV) is the age dating of archeological remains (i.e., the archeomagnetic dating technique). This application requires the local model of PSV that reflects non-dipole fields with regional differences. Until now, the tentative Korean paleosecular variation (t-KPSV) calculated based on JPSV (SW Japanese PSV) has been applied as a reference curve for individual archeomagnetic directions in Korea. However, it is less reliable due to regional differences in the non-dipole magnetic field. Here, we present PSV curves for AD 1 to 600, corresponding to the Korean Three Kingdoms (including the Proto Three Kingdoms) Period, using the results of archeomagnetic studies in the Korean Peninsula and published research data. Then we compare our PSV with the global geomagnetic prediction model and t-KPSV. A total of 49 reliable archeomagnetic directional data from 16 regions were compiled for our PSV. In detail, each data showed statistical consistency (N > 6, 𝛼95 < 7.8°, and k > 57.8) and had radiocarbon or archeological ages in the range of AD 1 to 600 years with less than ±200 years error range. The compiled PSV for the initial six centuries (KPSV0.6k) showed declination and inclination in the range of 341.7° to 20.1° and 43.5° to 60.3°, respectively. Compared to the t-KPSV, our curve revealed different variation patterns both in declination and inclination. On the other hand, KPSV0.6k and global geomagnetic prediction models (ARCH3K.1, CALS3K.4, and SED3K.1) revealed consistent variation trends during the first six centennials. In particular, the ARCH3K.1 showed the best fitting with our KPSV0.6k. These results indicate that contribution of the non-dipole field to Korea and Japan is quite different, despite their geographical proximity. Moreover, the compilation of archeomagnetic data from the Korea territory is essential to build a reliable PSV curve for an age dating tool. Lastly, we double-check the reliability of our KPSV0.6k by showing a good fitting of newly acquired age-controlled archeomagnetic data on our curve.

Target candidate fish species selection method based on ecological survey for hazardous chemical substance analysis (유해화학물질 분석을 위한 생태조사 기반의 타깃 후보어종 선정법)

  • Ji Yoon Kim;Sang-Hyeon Jin;Min Jae Cho;Hyeji Choi;Kwang-Guk An
    • Korean Journal of Environmental Biology
    • /
    • v.41 no.2
    • /
    • pp.109-125
    • /
    • 2023
  • This study was conducted to select target fish species as baseline research for accumulation analysis of major hazardous chemicals entering the aquatic ecosystem in Korea and to analyze the impact on fish community. The test bed was selected from a sewage treatment plant, which could directly confirm the impact of the inflow of harmful chemicals, and the Geum River estuary where harmful chemicals introduced into the water system were concentrated. A multivariable metric model was developed to select target candidate fish species for hazardous chemical analysis. Details consisted of seven metrics: (1) commercially useful metric, (2) top-carnivorous species metric, (3) pollution fish indicator metric, (4) tolerance fish metric, (5) common abundant metric, (6) sampling availability (collectability) metric, and (7) widely distributed fish metric. Based on seven metric models for candidate fish species, eight species were selected as target candidates. The co-occurring dominant fish with target candidates was tolerant (50%), indicating that the highest abundance of tolerant species could be used as a water pollution indicator. A multi-metric fish-based model analysis for aquatic ecosystem health evaluation showed that the ecosystem health was diagnosed as "bad conditions". Physicochemical water quality variables also influenced fish feeding and tolerance guild in the testbed. Eight water quality parameters appeared high at the T1 site, indicating a large impact of discharging water from the sewage treatment plant. T2 site showed massive algal bloom, with chlorophyll concentration about 15 times higher compared to the reference site.

Development and Testing of a RIVPACS-type Model to Assess the Ecosystem Health in Korean Streams: A Preliminary Study (저서성 대형무척추동물을 이용한 RIVPACS 유형의 하천생태계 건강성 평가법 국내 하천 적용성)

  • Da-Yeong Lee;Dae-Seong Lee;Joong-Hyuk Min;Young-Seuk Park
    • Korean Journal of Ecology and Environment
    • /
    • v.56 no.1
    • /
    • pp.45-56
    • /
    • 2023
  • In stream ecosystem assessment, RIVPACS, which makes a simple but clear evaluation based on macroinvertebrate community, is widely used. In this study, a preliminary study was conducted to develop a RIVPACS-type model suitable for Korean streams nationwide. Reference streams were classified into two types(upstream and downstream), and a prediction model for macroinvertebrates was developed based on each family. A model for upstream was divided into 7 (train): 3 (test), and that for downstream was made using a leave-one-out method. Variables for the models were selected by non-metric multidimensional scaling, and seven variables were chosen, including elevation, slope, annual average temperature, stream width, forest ratio in land use, riffle ratio in hydrological characteristics, and boulder ratio in substrate composition. Stream order classified 3,224 sites as upstream and downstream, and community compositions of sites were predicted. The prediction was conducted for 30 macroinvertebrate families. Expected (E) and observed fauna (O) were compared using an ASPT biotic index, which is computed by dividing the BMWPK score into the number of families in a community. EQR values (i.e. O/E) for ASPT were used to assess stream condition. Lastly, we compared EQR to BMI, an index that is commonly used in the assessment. In the results, the average observed ASPT was 4.82 (±2.04 SD) and the expected one was 6.30 (±0.79 SD), and the expected ASPT was higher than the observed one. In the comparison between EQR and BMI index, EQR generally showed a higher value than the BMI index.

Construction of Genetic Linkage Map and Identification of Quantitative Trait Loci in Populus davidiana using Genotyping-by-sequencing (Genotyping-by-sequencing 기법을 이용한 사시나무(Populus davidiana) 유전연관지도 작성 및 양적형질 유전자좌 탐색)

  • Suvi Kim;Yang-gil Kim;Dayoung Lee;Hye-jin Lee;Kyu-Suk Kang
    • Journal of Korean Society of Forest Science
    • /
    • v.112 no.1
    • /
    • pp.40-56
    • /
    • 2023
  • Tree species within the Populus genus grow rapidly and have an excellent capacity to absorb carbon, conferring substantial ability to effective purify the environment. Poplar breeding can be achieved rapidly and efficiently if a genetic linkage map is constructed and quantitative trait loci (QTLs) are identified. Here, a high-density genetic linkage map was constructed for the control pollinated progeny using the genotyping-by-sequencing (GBS) technique, which is a next-generation sequencing method. A search was also performed for the genes associated with quantitative traits located in the genetic linkage map by examining the variables of height and diameter at root collar, and resilience to insect damage. The height and diameter at root collar were measured directly, while the ability to recover from insect damage was scored in a 4-year-old breeding population of aspen hybrids (Odae19 × Bonghyeon4 F1) established in the research forest of Seoul National University. After DNA extraction, paternity was confirmed using five microsatellite markers, and only the individuals for which paternity was confirmed were used for the analysis. The DNA was cut using restriction enzymes and the obtained DNA fragments were prepared using a GBS library and sequenced. The analyzed results were sorted using Populus trichocarpa as a reference genome. Overall, 58,040 aligned single-nucleotide polymorphism (SNP) markers were identified, 17,755 of which were used for mapping genetic linkages. The genetic linkage map was divided into 19 linkage groups, with a total length of 2,129.54 cM. The analysis failed to identify any growth-related QTLs, but a gene assumed to be related to recovery from insect damage was identified on linkage group (chromosome) 4 through genome-wide association study.

Evaluation of Control Pollination Efficiency and Management Status in Control Pollinated Progeny Populations of Pinus densiflora using Pedigree Analysis based on Microsatellite Markers (소나무 인공교배 차대집단에서 Microsatellite marker 혈통분석을 이용한 인공교배 효율 및 관리상태 평가)

  • Tae-Lim Yeo;Jihun Kim;Dayoung Lee;Kyu-Suk Kang
    • Journal of Korean Society of Forest Science
    • /
    • v.112 no.2
    • /
    • pp.157-172
    • /
    • 2023
  • Controlled pollination (CP) is an important method in tree breeding programs because CP quickly generates desirable genotypes and rapidly maximizes genetic gains. However, few studies have evaluated the efficiency and success rate of CP in the breeding program of Pinus densiflora. To evaluate CP and the management of control pollinated progenies, we used 159 individuals in CB2 × KW40 or KW40 × CB2 populations that were established in 2015. After genotyping microsatellite loci, we estimated whether the number of primers was sufficient or not. Then, we performed pedigree analysis. The result showed that the number of primers was sufficient. By pedigree analysis, we found out that 60 of 159 individuals had been generated by the mating between CB2 and KW40. In the maternity analysis, there was evidence to indicate the possibility of management problems. Therefore, we excluded 54 individuals and repeated the pedigree analysis. In the second analysis, 47 of 105 individuals were generated by the mating between CB2 and KW40. To increase the efficiency of CP in tree breeding programs, several precautions are required. It is necessary to identify the exact clone names of the mother and father trees. In addition, CP processes should be performed properly, including deciding on the schedule of CP and the isolation of female strobili or flowers. Finally, the monitoring of hybrid progenies management after mating is important. Molecular markers should be used to identify the clone names of the mother and father trees and for monitoring post hoc management. This study provides a reference for tree breeding programs for the future control pollination of pine species.

Simultaneous determinations of anthracycline antibiotics by high performance liquid chromatography coupled with radial-flow electrochemical cell (고성능 액체 크로마토그래피/방사흐름 전기화학전지를 이용한 안트라사이클린계 항생제의 동시 정량)

  • Cho, Yonghee;Hahn, Younghee
    • Analytical Science and Technology
    • /
    • v.20 no.4
    • /
    • pp.308-314
    • /
    • 2007
  • The analytical method of HPLC with the radial-flow electrochemical cell (RFEC) has been developed to determine doxorubicin, epirubicin, nogalamycin, daunorubicin and idarubicin simultaneously by employing a reversed-phase chromatography. Anthracyclines were detected at -0.74 V vs. a Ag/AgCl (0.01 M NaCl) reference electrode, a potential of diffusion current plateau in the mobile phase. At a $V_f$ of 1.0 mL/min doxorubicin, epirubicin, daunorubicin and idarubicin appeared at a retention time ($t_r$) of 6.4 min, 7.4 min, 12.7 min and 18.4 min, respectively, while at a $V_f$ of 0.6 mL/min, doxorubicin, epirubicin, nogalamycin, daunorubicin and idarubicin appeared at a $t_r$ of 9.9 min, 11.5 min, 13.5 min, 19.6 min and 28.7 min, respectively. The linearity between each anthracycline injected ($2.40{\times}10^{-7}M{\sim}1.42{\times}10^{-5}M$) and peak area (charge) was excellent with the square of the correlation coefficient ($R^2$) higher than 0.999. The detection limits were $1.0{\times}10^{-8}M{\sim}1.5{\times}10^{-7}M$ for the five anthracyclines. Within-day precision for the five anthracyclines were in reasonable relative standard deviations less than 3 % ($1.00{\times}10^{-6}M{\sim}1.42{\times}10^{-5}M$) except the lower concentrations less than $0.7{\mu}M$. Solid phase extractions of $1.00{\times}10^{-5}M$ epirubicin, $0.48{\times}10^{-5}M$ nogalamycin and $1.52{\times}10^{-5}M$ daunorubicin from human serum with a $C_{18}$ cartridge resulted in 97 %, 100 % and 90 % of recoveries, respectively.

Effectiveness Analysis of HOT Lane and Application Scheme for Korean Environment (HOT차로 운영에 대한 효과분석 및 국내활용방안)

  • Choi, Kee Choo;Kim, Jin Howan;Oh, Seung Hwoon
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.29 no.1D
    • /
    • pp.25-32
    • /
    • 2009
  • Currently, various types of TDM (Transportation Demand Management) policies are being studied and implemented in an attempt to overcome the limitations of supply oriented policies. In this context, this paper addressed issues of effectiveness and possible domestic implementation of the HOT lane. The possible site of implementation selected for this simulation study is part of the Kyung-bu freeway, where a dedicated bus lane is currently being operated. Minimum length of distance required in between interchanges and access points of the HOT lane for vehicles to safely enter and exit the lane, and traffic management policies for effectively managing the weaving traffic trying to enter and exit the HOT lane were presented. A 5.2km section of freeway from Ki-heuing IC to Suwon IC and a 8.3km section from Hak-uei JC to Pan-gyo JC have been selected as possible sites of implementation for the HOT lane, in which congestion occurs regularly due to the high level of travel demand. VISSIM simulation program has been used to analyze the effects of the HOT lane under the assumption that one-lane HOT lane has been put into operation in these sections and that the lane change rate were in between 5% to 30%. The results of each possible scenario have proven that overall travel speed on the general lanes have increased as well by 1.57~2.62km/h after the implementation of the HOT lane. It is meaningful that this study could serve as a basic reference data for possible follow-up studies on the HOT lane as one effective method of TDM policies. Considering that the bus travel rate would continue increase and assuming the improvement in travel speed on general lanes, similar case study can be implemented where gaps between buses on bus lane are available, as a possible alternative of efficient bus lane management policies.

1-month Prediction on Rice Harvest Date in South Korea Based on Dynamically Downscaled Temperature (역학적 규모축소 기온을 이용한 남한지역 벼 수확일 1개월 예측)

  • Jina Hur;Eun-Soon Im;Subin Ha;Yong-Seok Kim;Eung-Sup Kim;Joonlee Lee;Sera Jo;Kyo-Moon Shim;Min-Gu Kang
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.25 no.4
    • /
    • pp.267-275
    • /
    • 2023
  • This study predicted rice harvest date in South Korea using 11-year (2012-2022) hindcasts based on dynamically downscaled 2m air temperature at subseasonal (1-month lead) timescale. To obtain high (5 km) resolution meteorological information over South Korea, global prediction obtained from the NOAA Climate Forecast System (CFSv2) is dynamically downscaled using the Weather Research and Forecasting (WRF) double-nested modeling system. To estimate rice harvest date, the growing degree days (GDD) is used, which accumulated the daily temperature from the seeding date (1 Jan.) to the reference temperature (1400℃ + 55 days) for harvest. In terms of the maximum (minimum) temperatures, the hindcasts tends to have a cold bias of about 1. 2℃ (0. 1℃) for the rice growth period (May to October) compared to the observation. The harvest date derived from hindcasts (DOY 289) well simulates one from observation (DOY 280), despite a margin of 9 days. The study shows the possibility of obtaining the detailed predictive information for rice harvest date over South Korea based on the dynamical downscaling method.

A Study on the Classification System of Cadastral Cultural Heritage : Focusing on LX museum collection (지적 문화유산 분류체계 연구 - LX국토정보박물관 소장품을 중심으로 -)

  • Kim, Ji-Hyun
    • Journal of Cadastre & Land InformatiX
    • /
    • v.54 no.1
    • /
    • pp.63-74
    • /
    • 2024
  • The fundamental basis for revitalizing cultural resources and developing content is national heritage(cultural property). In national heritage, cultural heritage is a tangible cultural heritage that represents the uniqueness of history and tradition, identity, and changes in life. In the case of museums, the collections (a museum-owned cultural heritage) represent the unique characteristics of the institution. In South Korea, it is recommended that museum collections be registered and used in the Cultural Heritage Standard Management System so that cultural heritage can be managed and utilized in connection with academics, industry, and administration. However, due to a lack of awareness of modern and contemporary heritage, the thematic classification chronology of the system was set mainly before the Joseon Dynasty, and a cultural heritage classification system suitable for national land information has not been established. Therefore, this study aims to propose a classification system for cadastral cultural heritage, based on the modern era when cadastral terminology was first used, using the cultural heritage owned by the LX Museum. Cadastral cultural heritage is characterized by the fact that although it is a field of specialized technology, the surveying or the production of it is not done by specific individuals only, and that while the production is professional, there are many educational aspects in its use. Therefore, unlike other specialized museum collections that are classified based on the functional aspects of their production methods, intended use, and creators, the classification method for cadastral cultural artifacts should be based on the characteristics of the cadastral tools and the outputs. This classification follows a three-tier stages with reference to the items in the Cultural Heritage Standard Management System. This classification aims at the effective use of knowledge by categorizing concepts and systematizing the subjects of data into a series of orders. A safe conservation and management environment for cadastral cultural heritage can be established, and academic and socio-cultural interpretation of the collection is possible by this classfication. Moreover, It is also expected to serve the basis for the national land information as well as searching for the national land information research, planning a exhibition, and the field of education in museum.