• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.131-139
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• 2023

In this study, we investigated pesticide residue levels in 535 domestically distributed agricultural products in South Korea using multi-residue analysis. Agricultural products from 13 regions, including Seoul, were pretreated using QuEChERS and d-SPE, and subsequently analyzed using LC-MS/MS and GC-MS/MS. Residual pesticides were detected in 288 (53.8%) out of the 535 samples, including 40 of apples, 40 of peppers, 33 of mandarins, 31 of peaches, and 144 other commodities. Furthermore, one sample of Korean cabbage exceeded the permitted maximum residue limit (MRL), diniconazole (0.18 mg/kg), detected at about twice the MRL. In total, 91 types of residual pesticides were detected, including fungicides (42), insecticides (48), and a nematicide. The most frequently detected pesticides were dinotefuran (91), carbendazim (75), tebuconazole (61), and pyraclostrobin (59). Our results showed that continuous monitoring of agricultural products is necessary.

• Korean Journal of Environmental Agriculture
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• v.39 no.1
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• pp.10-19
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• 2020

BACKGROUND: This study was to carry out risk assessment of contamination of cadmium (Cd), lead (Pb), and inorganic arsenic (I-As) in agricultural products of 25 crops from the abandoned mine areas. The 36 typical investigation sites located in Gyeongbuk provincial area were selected by considering the heavy metal levels, that had been known that the amount of the heavy metals exceeded the contamination level based on the previous survey. METHODS AND RESULTS: Cadmium, lead, and total arsenic (T-As) concentrations were determined using microwave device and ICP-MS. Inorganic arsenic was determined by HPLC-ICP-MS. The limits of quantification for heavy metals were 0.59 ㎍/kg for Cd, 0.42 ㎍/kg for Pb, 0.55 ㎍/kg for T-As, and sum of As (III) (1.74 ㎍/kg) and As (V) (2.25 ㎍/kg) for I-As, respectively. The contents of Cd, Pb, and I-As (only rice) were N.D.-0.958 mg/kg, N.D.-0.227 mg/kg, and 0.082 mg/kg, respectively, in the agricultural products. For risk assessment, dietary exposures of heavy metals through usual intake were 5.20×10^-4-7.15×10⁰ ㎍/day for Cd, 7.00×10^-5-7.75×10^-1 ㎍/day for Pb, and 1.17×10¹ ㎍/day for I-As, taking 0.01-14.37%, 0.01-2.05%, and 15.16% as risk indices, respectively. CONCLUSION: It requires to consider the critical levels of heavy metals in agricultural products due to unexpectedly high levels in a few places, while concentrations of heavy metals in the samples were relatively low in most areas.

• Journal of Digital Convergence
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• v.10 no.6
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• pp.61-69
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• 2012

The SW market has greatly growing up according as rapid progressing of the smart fusion, nowadays. But, the portion of Korea in the global SW market is no more than 2.2%. Especially, the portion of Korea's package SW is very much fragile than it of the global companies and lower than it of embedded SW in Korea. It is caused by weak competitiveness of Korea's package SW and the politic support of government is fainter than it of other SW kinds. So, this article will grasp the actual state of domestic package SW industry through data and case study, drew the improving problems of the package SW policy, and propose the cultivating policies of the package SW.

• Korean Chemical Engineering Research
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• v.47 no.4
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• pp.410-417
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• 2009

Carbon dioxide was absorbed into GMA solution in a stirred flat cell using mesoporous catalyst Imidazole-CP-MS41, which was synthesized by CP-MCM41 with imidazole. Experiments were carried out at a batch-type absorber with different conditions, varying reaction temperature, concentration of GMA, solvent but maintaining 50 rpm of agitation speed and 2 g of catalyst. Absorption rate of $CO_2$ was used to obtain the kinetics based on the film theory using zwitterion mechanism with 2 elementary reaction and the kinetics were correlated with the solubility parameter of the solvents.

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.126-132
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• 2014

This experiment was conducted to establish the in vitro propagation of Dendrobium moniliforme through protocorm like body (PLB) induction from the culture of leaf, stem and root explants. Frequency of PLB formation from root explants was higher than those of leaf and stem explants. PLB's proliferation in MS medium including 1.0 mg/L NAA was better than 1.0 mg/L IBA. Frequency of PLB's proliferation on medium with various concentrations of BA, Kinetin, Tidiazuron (0. 1.0, 3.0 mg/L) and NAA (0, 1.0 mg/L) was tested. The maximun proliferation of PLB's was obtained on MS medium supplemented with 3.0 mg/L BA and 1.0 mg/L NAA after 6 weeks of culture. Addition of 200 mg/L activated charcoal (AC) and 30 g/L sucrose was effective on PLB proliferation for D. moniliforme.

• Journal of Korea Society of Industrial Information Systems
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• v.29 no.3
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• pp.137-152
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• 2024

In order to derive a plan to increase the field effectiveness of the safety and health management(SHM) system, this study suggested plans for practical application of SHM system to the actual sites managed by the branch office of a public enterprise along with practical implications that should be considered. For this, in-depth interviews were conducted with employees in charge of safety and health work at the sites to analyze SHM system of the branch office, and the implementation processes and frameworks for establishing SHM system were suggested by grasping the actual conditions of the construction company performing the construction ordered by the branch office. This study shows that in order for SHM to be internalized in public enterprises, plans and performance indicators that can be applied in the field should be specifically presented in consideration of the hierarchical structure and processes of the organization performing the work, and a work environment should be created to focus on practical works related to safety and health.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1158-1164
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• 2011

5-Methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT), a psychoactive tryptamine derivative, is a hallucinogenic drug of abuse. In this study, 5-OH-DIPT and its metabolites were identified and the quantitative method was developed and validated by using hydrophilic interaction chromatography-tandem mass spectrometry (HILICMS/MS). Chromatographic separation was achieved on an Atlantis HILIC silica column ($5{\mu}m$, $100{\times}2.1\;mm$). The metabolites of 5-MeO-DIPT in rat urine were characterized via Q1 scanning and product ion scanning. As a consequence, 5-MeO-IPT, 5-OH-DIPT, 6-OH-5-MeO-DIPT and their glucuronide conjugates were detected and identified as the metabolites of 5-MeO-DIPT. Subsequently, a quantitative method for 5-MeO-DIPT and its major metabolites, 5-MeO-IPT and 5-OH-DIPT, was developed in multiple reactions monitoring (MRM) mode. The calibration curves for all analytes evidenced good linearity over the concentration range of 1-1000 ng/mL with linear correlation co-efficients ($r^2$) in excess of 0.99. The intra- and inter-day accuracy and precision were 92.2-110.2% and 1.5-9.9%, respectively.

• Analytical Science and Technology
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• v.25 no.1
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• pp.60-68
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• 2012

A gas chromatography-mass spectrometric (GC-MS) method was developed for determining 25 semivolatile organic compounds in water. A 1.0 L water sample was placed in a separatory funnel and saturated with NaCl, and the solution was extracted two times with 40 mL of methylene chloride. Under the established condition, the linear quantification range was 0.02-800 ng/L and the relative standard deviation was less than 15%. The method was used to analyze 16 surface water samples collected from various regions in Gum-River. The samples revealed SVOC concentrations in the range of 0.02-96.8 ng/L. Maximum concentrations of VOCs detected were not exceeded the EPA or Germany guidelines in any of the samples. The developed method may be valuable for monitoring SVOCs in water.

• Journal of Food Hygiene and Safety
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• v.32 no.4
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• pp.290-297
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• 2017

The purpose of this study was developed for the determination of tridemorph in agricultural commodities samples. Tridemorph residues in samples were extracted with acetonitrile, partitioned with saline water, and then purified using and aminopropyl ($NH_2$) SPE catridge. The purified samples were quantified and confirmed via liquid chromatograph-tandem mass spectrometer (LC-MS/MS) in positive ion mode using multiple reaction monitoring (MRM). Matrix-matched calibration curves were linear over the calibration ranges (0.005~2.5 ng) into a blank extract with $r^2$ > 0.999. The limits of detection and quantification were 0.001 and 0.005 mg/kg, respectively. The average recovery ranged between 75.9% and 103.7% at different concentration levels (LOQ, 10 LOQ, 50 LOQ, n = 5) with relative standard deviations (RSDs) less than 9.0%. An interlaboratory study was conducted to validate the method by Korea Advanced Food Research Institute. The average recovery ranged between 87.0% and 109.2% at different concentration levels (LOQ, $10{\times}LOQ$, $50{\times}LOQ$, n = 5) with relative standard deviations (RSDs) less than 8.0%. All values were consistent with the criteria ranges requested in the Codex guidelines (CAC/GL40, 2003) and Food Safety Evaluation Department guidelines (2016). The results prove that the developed analytical methods is accurate, effective and sensitive for tridemorph determination.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10b
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• pp.224-226
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• 1999

본 논문에서는 다양한 목적의 공동 작업 시스템에서 공통적으로 사용할 수 있으며, 플랫폼에 독립접인 웹 기반의 화이트 보드와 채팅을 설계하고 구현한 내용을 소개한다. 본 논문에서 구현한 시스템은 서버/클라이언트 구조로서, 서버와 클라이언트 모두 JAVA로 구현하였다. 그러므로 플랫폼에 독립적인 서버 시스템(application)을 구성할 수 있으며, 별도의 어플리케이션 없이도 웹 브라우저만 있으면 클라인언트의 접속이 가능하다. 멀티유저와 멀티작업그룹을 지원하기 위해서 서버에는 접속 관리자와 세션 관리자를 두었으며, 각각 쓰레드로 동작하여 서버의 부하를 줄이고, 또한 서버와 클라이언트간의 통신이 실시간으로 이루어지게 하였다. 웹 사이트와 MS Office 문서의 공유, 1:1대화, 작업 포인터 등의 기능을 지원하여 공동 작업의 효율을 증진시키고, 마치 동일한 공간에서 작업하고 있는 듯한 효과를 얻게 하였다.