• 한국지반환경공학회 논문집
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• 제11권5호
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• pp.61-67
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• 2010

본 연구는 GC/FID에서 염화유기용제(PCE와 TCE)와 그 부산물(cis-DCE, VC, 그리고 Ethylene)의 분석을 위하여 액-액추출법의 대안인 SPME방법을 연구하였다. 실험인자로써 fiber의 종류, 흡착 및 탈착시간, headspace의 부피, 염석효과, 그리고 교반효과에 대하여 실험을 실시하였다. 염화유기용제와 부산물의 분석을 위하여 fiber는 CAR/PDMS, 흡착과 탈착시간은 $250^{\circ}C$에서 20분과 5분, 염첨가량 25%와 교반이 병행되었을 때에 최적의 분석조건으로 도출되었다. CAR/PDMS fiber에서 분석물의 추출감도는 PCE>TCE>cis-DCE>VC>Ethylene순으로 조사되었다. 염화유기용제와 부산물의 농도 $10{\mu}g/L$에서 $500{\mu}g/L$까지의 직선상의 상관계수($R^2$)는 0.912에서 0.999로 조사되었으며, $500{\mu}g/L$(5회 분석)일 때에 상대표준편차(% RSD)는 2.1%에서 3.6%로 나타났다. 마지막으로 본 연구에서 염화유기용제와 부산물의 검출한계(LOD)는 $0.5{\mu}g/L$에서 $10{\mu}g/L$로 관측되었다.

• 한국위성정보통신학회논문지
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• 제9권2호
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• pp.96-100
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• 2014

최근 전 세계적으로 운영되는 하 폐수 처리시설 관리에 있어 환경 보호를 위한 엄격한 규제로 수질오염 측정 시스템에 관한 시스템이 부각되고 있으며, 대형시설 또는 산업단지 내의 자체 하수처리장이 건립되면서 하수처리장의 효율성 및 자동차에 대한 연구 및 개발이 활성화되고 있다. 하지만 기존 하수처리 시스템은 하 폐수에 특화된 수질감시 기술 및 이를 실시간 전송하기 위한 신뢰성 있는 네트워크 구축이 미흡한 실정이다. 따라서, 본 논문은 하수처리시설에서 슬러지의 농도를 효과적으로 측정 가능한 슬러지 멀티메터의 데이터를 수집하고 멀티메터를 제어하기 위한 근거리 무선 네트워크의 데이터 구조 설계를 제안하였다. 근거리 무선 네트워크를 통해 수집된 데이터는 중앙 모니터링 시스템으로 전달되어 실시간으로 데이터를 누적하고 통계를 산출하여 하수 처리 시설의 상태를 모니터링이 가능하다. 제안된 시스템은 근거리 무선 네트워크 시스템으로 IEEE 802.15.4와 비콘(Beacon)을 사용하여, 중앙시스템에서 실시간 상태 확인이 가능하도록 IEEE 802.11네트워크를 구성하였으며, 하수처리시설에 슬러지 멀티 메터를 설치하고 통신 네트워크를 구축해서 그 효율성을 입증함으로써 제안 기술의 유용성을 확인하였다.

• 한국임상약학회지
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• 제32권1호
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• pp.20-26
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• 2022

Background and objective: The Seoul National University Bundang Hospital (SNUBH) implemented ward-based clinical pharmacy system with designated pharmacists in 10 general wards. Designated pharmacists conduct inpatient medication review, medication intervention, and medication consultation, and provide drug information for health care providers. This study aimed to evaluate the clinical pharmacy services and to examine the perception and expectations of health care providers on the services provided by the designated pharmacists in general wards. Methods: A survey was constructed to include questions on the health care providers' recognition, satisfaction, and perceived needs of designated pharmacists. We determined the frequency and type of interventions of ward pharmacist and their acceptance rate through a retrospective observational study using electronic medical records. Results: A total of 59 health care providers responded the questionnaire and 79.7% of the respondents reported moderate to high levels of satisfaction. Satisfaction with the services was positively associated with clinical interventions and nutrition support team (81.4%). Of 59 respondents, 88.1% agreed that preventing drug-related problems by designated pharmacists' activities were effective. The most common interventions included inadequate dosage (27.4%), omission and additional prescription (14.6%) and inadequate drug form (9.6%). The acceptance rate of intervention was 91.5%, and 151 potentially serious risks and 523 significant risks were prevented by the intervention. Conclusion: Positive results were confirmed in the awareness, satisfaction, and perceived needs of the health care providers for designated pharmacists. Expansion of the ward-based clinical pharmacy system with designated pharmacists to other wards may be considered.

• 대한임상독성학회지
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• 제21권2호
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• pp.69-80
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• 2023

Purpose: Suicide ranks among the top causes of death among youth in South Korea. This study aimed to identify the characteristics of suicidal individuals treated at emergency departments between 2011 and 2020. Methods: A retrospective analysis was conducted using data from January 2011 to December 2020 in the Injury Surveillance Cohort, a prospective registry. Patients' sex, age, mortality, methods of self-harm, and previous suicide attempts were analyzed. The methods of self-harm were categorized into falls, asphyxiation, blunt injuries, penetrating injuries, poisoning, and others. Sub-groups with and without poisoning were compared. Results: The proportion of self-harm/suicide attempts increased from 2.3% (2011) to 5.0% (2020). The mortality rate decreased from 10.8% (2011) to 6.3% (2020). Poisoning was the most common method (61.7%). Mortality rates ranged from 42.0% for asphyxiation to 0.2% for blunt injuries. Individuals in their 20s showed a marked increase in suicide/self-harm attempts, especially in the last three years. A large proportion of decedents in their 70s or older (52.6%) used poisoning as a method of suicide. The percentage of individuals with two or more previous attempts rose from 7.1% (2011) to 19.7% (2020). The death rates by poisoning decreased from 7.7% (2011) to 2.5% (2020). Conclusion: Our findings underscore the urgent need for targeted interventions and suicide prevention policies. Managing and reducing suicide and self-harm in emergency settings will require a focus on poisoning, the 10-29 age group, and the elderly. This paper will be valuable for future policies aiming to reduce the societal burden of suicide and self-harm.

• Geomechanics and Engineering
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• 제37권6호
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• pp.599-614
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• 2024

To evaluate the safety status of deteriorated segments in a submarine shield tunnel during its service life, a seepage model was established based on a cross-sea shield tunnel project. This model was used to study the migration patterns of erosive ions within the shield segments. Based on these laws, the degree of deterioration of the segments was determined. Using the derived analytical solution, the internal forces within the segments were calculated. Lastly, by applying the formula for calculating safety factors, the variation trends in the safety factors of segments with different degrees of deterioration were obtained. The findings demonstrate that corrosive seawater presents the evolution characteristics of continuous seepage from the outside to the inside of the tunnel. The nearby seepage field shows locally concentrated characteristics when there is leakage at the joint, which causes the seepage field's depth and scope to significantly increase. The chlorine ion content decreases gradually with the increase of the distance from the outer surface of the tunnel. The penetration of erosion ions in the segment is facilitated by the presence of water pressure. The ion content of the entire ring segment lining structure is related in the following order: vault < haunch < springing. The difference in the segment's rate of increase in chlorine ion content decreases as service time increases. Based on the analytical solution calculation, the segment's safety factor drops more when the joint leaks than when its intact, and the change rate between the two states exhibits a general downward trend. The safety factor shows a similar change rule at different water depths and continuously decreases at the same segment position as the water depth increases. The three phases of "sudden drop-rise-stability" are represented by a "spoon-shaped" change rule on the safety factor's change curve. The issue of the poor applicability of indicators in earlier studies is resolved by the analytical solution, which only requires determining the loss degree of the segment lining's effective bearing thickness to calculate the safety factor of any cross-section of the shield tunnel. The analytical solution's computation results, however, have some safety margins and are cautious. The process of establishing the evaluation model indicates that the secondary lining made of molded concrete can also have its safety status assessed using the analytical solution. It is very important for the safe operation of the tunnel and the safety of people's property and has a wide range of applications.