• 한국식품위생안전성학회지
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• 제37권5호
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• pp.297-305
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• 2022

산화방지제는 활성 산소에 의한 지질 산패를 방지하여 식품의 보존성을 증대하는 식품첨가물이다. 본 연구에서는 합성 산화방지제 5종 (Butylated hydroxyanisole (BHA), Butylated hydroxytoluene (BHT), Tertiary butylhydroquinone (TBHQ), Propyl gallate (PG), Disodium ethylenediaminetetraacetic acid(EDTA·2 Na))을 이용하여 HPLC-UVD 분석법에 대한 유효성 검증 및 합성 산화방지제가 표시된 실제 식품 속 함량 분석을 진행하였다. 직선성(R²)은 평균 0.9997, 검출한계(Limit of detection, LOD)와 정량한계(Limit of quantification, LOQ)는 각각 0.02-0.53과 0.07-1.61 mg/kg으로 산출하였다. 일내 및 일간 정확성과 정밀성 산출을 위하여 합성 산화방지제 4종은 콩기름과 과자, EDTA는 통조림과 마요네스를 이용하였다. 정확성과 정밀성 결과, 일내와 일간 각각 83.2±0.7-97.8±4.4와 86.2±3.3-98.3±2.1 및 0.1-6.4와 0.7-5.7 %RSD로 산출되었다. 또한 FAPAS QC material을 이용하여 실험실간 정확성 및 정밀성 검증을 진행하였으며 이는 AOAC가 제시한 가이드라인에 적합함을 확인하였다. 측정불확도 역시 CODEX에서 제시한 범위인 16% 이하인 것을 확인하였다. 따라서 본 연구를 통하여 국민 건강의 안전을 제고하기 위한 국내 산화방지제의 섭취량 및 위해성 평가를 위한 기초자료로 활용될 수 있을 것으로 사료된다.

• Ecology and Resilient Infrastructure
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• 제10권3호
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• pp.51-63
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• 2023

하천내 수목관리는 홍수와 생태 관리의 균형점을 찾는다는 점에서 매우 중요하며 이를 위해서는 수목이 하천 수위에 미치는 영향을 정확하게 평가할 필요가 있다. 본 연구에서 수목에 작용하는 항력을 고려하는 수목조도공식 8개에 대해 검토하여 실무 수리계산의 관점에서 수목 조도계수 공식의 특성과 적용성을 평가하였다. 개별 수목 조도계수 공식의 수심별 조도계수 산정 특성을 비교하고, 수관부 영향, 수목밀도와 직경 영향, 수목 강성계수 영향, 수위 산정 결과 등을 분석하였다. 동일 조건 수심별 조도계수 비교를 통해 Kouwen and Fathi-Moghadam 공식과 Fischenich 공식은 타 공식에 비해 과도한 조도계수를 산정하였다. 수관부, 수목 직경, 수목 밀도 등은 공식에 따라 상이한 경향을 나타내나 과도한 특이점은 없는 것으로 나타났다. 수목 강성계수를 고려하는 Freeman et al. 공식과 Whittaker et al. 공식은 강성계수에 따라 조도계수가 매우 큰 차이를 나타낸다. 8개 공식의 조도계수 산정 결과를 이용하여 국내 중소규모 가상 하천에 적용한 결과 최대 약 0.2 - 0.4 m 정도의 수위 상승효과를 나타내고 있다. 이상의 검토를 통해 유사한 특성을 가지며 입력자료의 불확실성이 낮은 Baptist et al., Huthoff et al., Cheng, Luhar and Nepf 등의 4개 공식이 실무 적용에 적합한 것으로 판단하였다.

• Korean Journal of Radiology
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• 제21권12호
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• pp.1294-1304
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• 2020

Objective: To determine whether T1 mapping could monitor the dynamic changes of injury in myocardial infarction (MI) and be histologically validated. Materials and Methods: In 22 pigs, MI was induced by ligating the left anterior descending artery and they underwent serial cardiovascular magnetic resonance examinations with modified Look-Locker inversion T1 mapping and extracellular volume (ECV) computation in acute (within 24 hours, n = 22), subacute (7 days, n = 13), and chronic (3 months, n = 7) phases of MI. Masson's trichrome staining was performed for histological ECV calculation. Myocardial native T1 and ECV were obtained by region of interest measurement in infarcted, peri-infarct, and remote myocardium. Results: Native T1 and ECV in peri-infarct myocardium differed from remote myocardium in acute (1181 ± 62 ms vs. 1113 ± 64 ms, p = 0.002; 24 ± 4% vs. 19 ± 4%, p = 0.031) and subacute phases (1264 ± 41 ms vs. 1171 ± 56 ms, p < 0.001; 27 ± 4% vs. 22 ± 2%, p = 0.009) but not in chronic phase (1157 ± 57 ms vs. 1120 ± 54 ms, p = 0.934; 23 ± 2% vs. 20 ± 1%, p = 0.109). From acute to chronic MI, infarcted native T1 peaked in subacute phase (1275 ± 63 ms vs. 1637 ± 123 ms vs. 1471 ± 98 ms, p < 0.001), while ECV progressively increased with time (35 ± 7% vs. 46 ± 6% vs. 52 ± 4%, p < 0.001). Native T1 correlated well with histological findings (R² = 0.65 to 0.89, all p < 0.001) so did ECV (R² = 0.73 to 0.94, all p < 0.001). Conclusion: T1 mapping allows the quantitative assessment of injury in MI and the noninvasive monitoring of tissue injury evolution, which correlates well with histological findings.

• 한국환경보건학회지
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• 제45권6호
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• pp.577-582
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• 2019

Objectives: The purpose of this survey was to assess the concentrations of heavy metals in the atmosphere of Pocheon City by measuring heavy metals in the industrial complex area and at the city air measuring station, and also to assess the degree of impact that the industrial area has on urban air quality. Methods: Sampling was carried out between February 2018 and November 2018 at two sites in the industrial complex and in the city air monitoring stations. Results: At the industrial complex in Pocheon City, air pollutant emitting businesses were emitting concentrations of fine dust (PM₁₀) between 45 and 60 ㎍/㎥ higher than in the city air. The daily maximum concentrations of lead (Pb), manganese (Mn), and cadmium (Cd) in the industrial complex are below the WHO recommendation standard (annual average), and the impact on the urban atmosphere is judged to be insignificant. Three to five percent of fine dust (PM₁₀) consists of metallic materials, and as the fine dust increased, metals were detected proportionally. Although cadmium (Cd) and beryllium (Be) were not detected in the city air in Pocheon and chromium (Cr), copper (Cu), and arsenic (As) were found to be 50 percent or less, it is deemed that copper (Cu) was detected at unusually high levels due to unknown air pollutants, which requires regular heavy metal measurement and cause verification. Conclusions: An analysis of the heavy metals in the industrial zone and the urban atmosphere in Pocheon City in this study showed that the linear relationship of heavy metals in the industrial zone, or the direct impact relationship, on the heavy metals in the urban atmosphere could not be estimated. The sampling device for equivalent assessment of particulate matter installed at air pollution monitoring stations is highly likely to be used for analysis of fine dust and heavy metals.

• 한국건설관리학회논문집
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• 제9권1호
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• pp.107-117
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• 2008

국내 건설산업은 해외 시장에서 경쟁력을 높이기 위해 각종 R&D투자를 늘리고 있는 실정으로 본 연구에서는 국내 건설산업이 해외 건설시장에서 경쟁력을 보유하고 있는 대표 건설상품에 대한 경쟁력을 종합적이고 다각적으로 평가하였다. 이를 위하여 기존 연구에서 실시한 기업의 경쟁력과 기술수준을 평가한 자료를 근거로 기술수준을 측정할 기술수준지표와 기술수준 측정방법론을 선정하였으며, 기존연구에서 부족하였던 기술수준 및 기술경쟁력 평가의 심층성에 대한 보완 방안으로 해외 경쟁력 보유 상품을 선별한 후, 관련 업무 전문가를 대상으로 기술수준을 평가하였다. 전문가 대상 요소는 '기술경쟁력', '경영 및 지원 경쟁력'을 대상으로 실시하였으며 각 요소의 평가 점수를 통하여 선진국과의 경쟁력 보유여부를 평가하였다. 이러한 평가결과를 토대로 국내 건설 산업이 시장측면이나 기술측면에서 해외시장에서 경쟁이 가능한 유망 상품을 도출하고 국제경쟁력을 증대할 수 있는 방안에 대하여 연구를 진행하였다.

• 대한한의학방제학회지
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• 제15권2호
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• pp.35-45
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• 2007

Objective : The purpose of this report was to provide the information activity and safety of Palmul-tang by analyzing domestic/international papers and theses about Palmul-tang, Methods: Domestic/international papers and theses related to Palmul-tang were reviewed and analyzed, These papers were then classified by year, experimental method and subject, Results: The following results were obtained in this study. 1. The study of Palmul-tang started from 1985 and was continuously increased. The study was mainly forcused on experimental model rather than clinical study. 2. As these studies were classified by subject, papers related to immune intensification were most abundant by 20 papers, Besides there were several papers related to cardiovascular activity, reproductive activity, anti-apoptotic activity and cerebral hemodynamics. 3. Among the papers related to immune intensification. the studies on recovery of fatigue were mostabundant by 10 papers and the studies of on immune cell and cytokine express were six. In addition to. several studies were associated with anti-cancer activity and anti-allergic activity. Recovery of fatigue was determined by measurement of fatigue markers in a living body such as lactate. CPK, pyruvate and triglyceride and assessment of exercise capability of animals such as swimming test. slopped plate test. Rota-rod test, and activity cage test after Palmul-tang treatment. 4. According to experimental data. it is supported that Palmul-tang has been used as Qi and Blood intensifier with immune intensification and recovery of fatigue. 5. The paper related to safety of Palmul-tang was only one paper which is studied on acute toxicity of Palmul-tang with experiment with ICR mouse. There was no study on evaluating safety by observing liver and kidney functions after Palmul-tang treatment Conclusion: Palmul-tang is being used in various ways associating with immune intensification. cardiovascular activity and reproductive activity. However. studies on efficacy and mechanism of Palmul-tang should be conducted at the molecular biology level and studies on safety of Palmul-tang need to be completed at the clinical level.

• 대한두경부종양학회지
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• 제32권1호
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• pp.1-5
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• 2016

Objectives: Frey's syndrome is an infrequent complication after parotidectomy and its incidence varies from 23.5% to 50.8% in the literature. The objective of this study was to evaluate the actual incidence and clinical characteristics of Frey's syndrome. Methods: We analyzed 31 patients who underwent parotidectomy and serial Minor's starch-iodine test. The mean follow-up period was $66{\pm}26.1$ months (range, 24-118 months). The Frey's syndrome was analyzed using a questionnaire for the assessment of the subjective symptom and Minor's starch-iodine test for the objective measurement at 1, 3, 6, and 12 months after the surgery and then every 6 or 12 months. Minor's starch-iodine test was graded from 0 to 3 according to the area of discolorization. Results: Frey's syndrome occurred in 11 patients (35.5%) on the Minor's starch-iodine test. The mean onset of Frey's syndrome on the starch-iodine test was $13.6{\pm}10.4$ months after parotidectomy. Sixteen patients (51.6%) complained about gustatory sweating and flushing. The onset of the subjective symptom was $11.27{\pm}6.96$ months after the surgery. There was a significant correlation between the grade of the starch-iodine test and the severity of subjective symptoms (P <0.001). Various factors including size and location of tumor, incision method, and extent of parotidectomy did not correlate with the Frey's syndrome. Conclusion: The incidence of Frey's syndrome was 35.5% on the Starch-Iodine test, and the onset was about postoperative 13.6 months.

• Asian Spine Journal
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• 제12권6호
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• pp.1106-1116
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• 2018

Study Design: Prospective observational study. Purpose: To evaluate the disability domains relevant to Indian patients with low backache and propose a modified disability questionnaire for such patients. Overview of Literature: The Oswestry Disability Index (ODI) is a self-reported measurement tool that measures both pain and functional status and is used for evaluating disability caused by lower backache. Although ODI remains a good tool for disability assessment, from the Indian perspective questions related to weight lifting and sexual activity of ODI are questioned in some of the earlier studies. Activities of daily living in Indian patients vary substantially from those in other populations and include activities like bending forwards, sitting in floor and squatting which are not represented in the ODI. Methods: In this prospective observational study, a seven-step approach was used for the development of a questionnaire. Thirty patients were interviewed to identify the most challenging issue they faced while performing their daily activities (by free listing) and understand how important the questionnaire items were in terms of the standard ODI. Thus, a comprehensive disability questionnaire comprising 14 questions was developed and administered to 88 patients. Both qualitative (interviews) and quantitative methods (to establish the validity, reliability, and correlation with the Visual Analog Scale [VAS] and Rolland Morris disability questionnaire) were used to identify the 10 questions that best addressed the disability domains relevant to Indian patients. Results: According to free listing, four new questions pertaining to bending forward, sitting on the floor, walking on uneven surfaces, and work-related disabilities were included. In the second phase, wherein the questionnaire with 14 items was used, 56.8% patients did not answer the questions related to sexual activity, whereas 23.8% did not answer those related to walking on uneven surfaces. The modified questionnaire demonstrated good internal consistency (Cronbach's alpha=0.892) and correlation with the Rolland Morris questionnaire (Cronbach's alpha=0.850, p>0.05), as well as with the VAS score for disability (Cronbach's alpha=0.712, p>0.05) and pain (Cronbach's alpha=0.625, p>0.05). Conclusions: A modified disability questionnaire that was designed by adding two questions related to bending forward and work status and removing questions related to sexual activity and weight lifting or traveling (depending on the occupation) can help evaluate disability caused by back pain in Indian population.

• 감성과학
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• 제14권4호
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• pp.503-512
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• 2011

최근 HCI 분야에서 정서 인식은 정서 지능을 구현하기 위한 핵심적인 단계 중의 하나이다. 생체신호를 이용하여 정서 인식을 시도하는 연구들이 시도되고 있으나, 기본 정서 이외의 다른 정서에 대한 연구는 거의 이루어지지 않았다. 본 연구의 목적은 무료함, 통증, 그리고 놀람의 세 가지 정서 간 자율신경계 반응의 차이를 확인하는 것이다. 실험자는 217명의 실험참여자(남 96명)들을 대상으로 시/청각 자극을 조합하여 무료함과 놀람 정서를 유발하였고, 혈압기를 이용하여 통증 정서를 유발하였다. 정서 자극이 제시되는 동안 피부전기활동, 피부온도, 심전도와 광혈량도를 측정하였고, 실험참여자들이 경험한 정서 범주와 강도를 정서평가척도 상에 평정하게 하였다. 정서 자극에 대한 평가 결과, 사용된 정서 자극은 평균 92.5%의 적합성과 5.43의 효과성을 보였는데, 이는 각 정서 자극이 해당 정서를 효과적으로 유발한 것을 의미한다. 자율신경계 측정 결과, 피부전기활동, 피부온도, 심박률, 심박률의 저주파수 성분과 평균 혈류량은 안정 상태와 정서 상태 간의 유의한 차이를 보였다. 또한 각 정서에 의해 유발된 자율신경계 반응은 정서 간에도 유의한 차이가 있는 것으로 나타났다. 이러한 결과는 정서이론의 확장과 자율신경계 반응 측정 지표를 활용하여 정서를 인식하는 알고리즘 및 인간 정서를 변별하는 컴퓨터 시스템 개발에 응용 가능할 것이다.

• Safety and Health at Work
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• 제9권3호
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• pp.356-359
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• 2018

This case report attempts to present a case of acute toxic hepatitis in fire extinguisher manufacturing workers exposed to 2,2-dichloro-1,1,1-trifluoro-ethane (HCFC-123) in August 2017 in Korea. Twenty-two-year-old male workers were exposed to HCFC-123 for 1.5 hours one day and for 2.5 hours the other day, after which one worker died, and the other recovered after treatment. The workers were diagnosed with acute toxicity of hepatitis. However, exposure levels of HCFC-123 were not known with no work environment measurement done. Therefore, this study was conducted to estimate the exposure concentration of HCFC-123 via a job simulation experiment. In the simulation, the HCFC-123 exposure concentration was measured with the same working practice and working time as with the workers aforementioned. As a result, the workers who infused HCFC-123 into storage tanks were estimated to be exposed to HCFC-123 at a concentration of $20.65{\pm}10.81ppm$, and a mean concentration of area samples within a working radius were estimated as $70.30{\pm}18.10ppm$. Valve assembly workers working on valves of a fire extinguisher filled with HCFC-123 were exposed to HCFC-123 at concentrations of $91.65{\pm}4.03ppm$ and $115.55{\pm}7.28ppm$, respectively, in the simulation, and area samples simulated within the working radius were also found to be high with concentrations of $122.75{\pm}91.15ppm$ and $126.80{\pm}60.25ppm$, respectively. Nitrogen gas packing workers, who did not handle HCFC-123 directly, were exposed to the agent at a concentration of $71.80{\pm}8.49ppm$. These results suggest that exposure to HCFC-123 at high concentrations for 1.5-2.5 hours caused acute toxic hepatitis in two workers.