• 대한환경공학회지
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• 제22권12호
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• pp.2141-2148
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• 2000

본 연구는 무연탄올 원료로 제조한 활성탄의 활성화 시간과 burn-off에 따른 세공구조의 변화를 고찰한 것으로 77K에서 질소 흡착실험에 의해 특성을 분석했다. 활성화 시간의 증가에 따라 burn-off는 거의 선형적으로 증가하며, burn-off를 증가시킴에 따라 제조된 활성탄의 총세공부피와 BET 비표면적은 증가했다. $800^{\circ}C$의 활성화는 $950^{\circ}C$의 활성화에 비해 미세세공(micropore)을 많이 생성시켰고, 동일한 burn-off에서는 저온에서 활성화시킨 활성탄에 미세세공이 발달하고 고온에서 활성화시킨 활성탄에 중간이상의 세공이 더 발달해 있었다. 수증기 활성화에 의해서는 직경 $100{\AA}$ 이하의 세공이 주로 발달되었으며 특히 $6{\sim}40{\AA}$ 범위의 세공은 burn-off의 정도에 따라 상당히 발달됨을 알 수 있었다.

• Journal of Ecology and Environment
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• 제33권4호
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• pp.351-361
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• 2010

The primary purposes for using fire are to enhance marsh vegetation to support waterfowl, and to manage invasive plant species. The study was conducted for two consecutive years in 2004 and 2005, investigating the effects of prescribed fire regimes on vegetation biomass in tidal brackish marsh areas of the Blackwater National Wildlife Refuge located on the eastern shore of Maryland, USA, that are under relatively similar environmental conditions. Four different burn regimes (i.e., annual burn, 3-5 year burn, 7-10 year burn, and no burn) were applied in the study. Above- and below-ground vegetation biomass samples as affected by the different burn regimes were harvested in each year for five plant species native to the marsh; Distichlis spicata, Spartina alterniflora, Schoenoplectus americanus, Spartina cynosuroides and Spartina patens. No significant difference was found either in total above-ground biomass or in above-ground biomass by species between burn regimes in 2004. However, more total above-ground biomass was produced in annual burn regime in 2005 than in the other burn regimes. There were no consistent effects of burning on vegetative biomass production by species, but it seemed D. spicata was somewhat benefited by prescribed burning for its biomass production. Moreover, the stem density for D. spicata under annual burn regime was significantly higher than that in the other burn regimes, showing some positive effects of burning on vegetation. The below-ground biomass was significantly greater in 2004 than in 2005, yet with no significant difference between burn regimes in either year. A longer-term monitoring is strongly recommended.

• 정보과학회 논문지
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• 제43권10호
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• pp.1131-1143
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• 2016

수십억 개 간선들로 구성된 대용량 그래프를 어떻게 효과적으로 압축할 수 있을까? 정점 재배치를 통해 인접 행렬의 0이 아닌 값들을 집중시키면 그래프를 효율적으로 압축할 수 있을 뿐 아니라 페이지랭크 등 여러 그래프 마이닝 알고리즘의 수행 속도를 개선할 수 있다. 최신 정점 재배치 기법인 SlashBurn은 실세계 네트워크의 멱법칙 특성을 활용하는 실세계 그래프에 효과적인 방법이다. 하지만 단일 머신 기반으로 설계되어 대용량 그래프에 대해 처리 속도가 현저히 느려지거나 적용이 불가능한 한계가 있다. 본 논문에서는 이러한 한계를 극복하기 위한 분산 SlashBurn을 제안한다. 분산 SlashBurn은 대규모의 정점 재배치 프로세스를 분산 처리하여 대용량 그래프를 기존 방법보다 훨씬 빠르고 확장성 있게 처리한다. 대용량 실세계 그래프들에 대한 실험 결과, 분산 SlashBurn은 단일 머신 SlashBurn보다 45배 이상 빠르게 동작하였고, 16배 이상 큰 그래프를 처리할 수 있었다.

• Archives of Plastic Surgery
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• 제33권5호
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• pp.581-586
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• 2006

Purpose: Pediatric burn still generates social problem leading to physical and mental sequelae for ages. We studied to help make a program for the prevention of pediatric burn. Methods: We analyzed retrospectically 2759 acute burn patients under the age of 15 years in recent 5years (January 2000 - December 2004). Results: 1553 males and 1226 females were investigated, with a male to female ratio of 1.25 : 1. The greatest number of burn patients were those with an age of 1 - 2 years(1435, 52%). Scalding burn was the most common cause of injury, which accounted for 1980 (71.8%) patients, followed by contact burns(286, 10.4%), flame burn(229, 8.3%), steam burn(141, 5.1%). Especially steam burn was the second cause of injury in the age under 1 year, while flame burn was the same in the age over 3 years. During recent 5 years, incidence of contact burn increased over twofold despite the others did not changed substantially. Variation of seasonal incidence is minimal and most of the patients(2545 cases, 92.2%) had burns of ${\leq}20%$ TBSA. The median hospital stay was 18.3 days, and the rate of operation was 35.4% with an high rate in electrical burn(70.6%), steam burn(68.8%), contact burn(65%). 27 patients died in this series, which yielded a mortality rate of 1%. Conclusion: We expect that these data will be used as a basis for prevention of pediatric burn.

• 대한화상학회지
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• 제19권1호
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• pp.12-15
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• 2016

Purpose: Firefighters are vulnerable to burn injury during firefighting. In extensive fires, conducted heat and radiant heat can cause burn injury even though firefighters are not directly exposed to fire. There has been increasing interest in the health problems of firefighters considerably since Hongje-dong fire of 2001, which claimed the lives of six fireman. However, there have been no studies done on the characteristics of firefighter burn injuries in South Korea. Therefore, we investigated the characteristics of firefighter burn injuries in a burn center. Methods: A retrospective, single-center research was performed between Jan 2006 to Dec 2015. 24 firefighters came to the burn center. The electronic medical records of patients were reviewed. Results: Flame burns (87.5%) were the major cause of burn in firefighter. All the patients suffered second-degree or third-degree burns. Mean burn size was 6.1±6.7%. 22 of 24 patients were hospitalized and 2 of 22 hospitalized patients admitted to intensive care unit. Mean length of hospitalization was 29.1±23.7 days and mean length of intensive care unit hospitalization was 6.0±1.4 days. The face was the site most commonly burned, representing 25.8% of injuries. The hand/wrist, upper extremity, and neck were the next largest groups, with 19.4, 12.9, 11.3% of the injuries, respectively. Conclusion: Firefighter burn injuries occur to predictable anatomic sites with common injury patterns. The burn size was small but, admitted patients need about 30 days of hospitalization.

• 대한화상학회지
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• 제22권1호
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• pp.10-14
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• 2019

Purpose: To find progression and prognosis of pancreatitis developed in massive burn patients through retrospective analysis. Methods: A retrospective study was conducted on 32 patients with abnormal increase of serum lipase level among 2523 acute burn patients admitted to our burn center from January 1, 2017 to June 30, 2018. Pancreatitis in this study was defined as a serum lipase concentration level that is higher than 180 IU/L which is three times more than the normal level (less than 60 IU/L). In this study, a retrospective analysis was performed on patients with serum lipase level higher than 300 IU/L to better understand causality of burns and pancreatitis. Results: 32 patients (1.27%) had serum lipase level higher than 180 IU/L among 2523 acute burn subjects. And 13 patients (0.52%) of these 32 patients had serum lipase level elevated more than 300 IU/L. The study indicated serum lipase level was increased around 7 days after the injury. It returned to normal level early as after 1 to 2 weeks and late as after 4 to 6 weeks of injury. The serum amylase level was increased as similar modality as to the serum lipase level increase. The serum bilirubin, AST, ALT, LD, and GGT were also observed to be elevated when serum lipase was more than 1000 IU/L. Conclusion: The pancreatitis developed in burn patients are mostly as mild symptom. It could due to the ischemic injury and can easily be treated by a temporary fasting, TPN, and Gabexate intravenous injection.

• 대한의생명과학회지
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• 제10권2호
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• pp.107-113
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• 2004

This study was conducted to investigate an effect of Mori Cortex in the cardiac injury following dermal scald burn in rats. Sprague-Dawley rats were induced scald bum (15％ of total body surface area). Heart was removed at 5 h postburn and examined with biochemical assay, ultrastructural observations and stereological analysis. The activity of serum aspartate aminotransferase and creatinine was increased at 5 h postburn compared with them of control. Administration of heat extracts of Mori Cortex after scald burn inhibited the production of KC (neutrophil chemoattractant cytokine) and increased the activity of protein kinase C (PKC) in heart tissue. The activity of myeloperoxidase (MPO) in heart tissue was decreased both at 5 h postburn and in case of Mori Cortex administration after scald burn. Ultrastructurally, many contraction bands and separation of intercalated disk induced by scald burn were decreased by administration of heat extracts of Mori Cortex. In stereological analysis, administration of Mori Cortex after scald burn resulted the volume densities of myofibril and mitochondria were increased compared with them of burn control. These data suggest that Mori Cortex may be a useful stuff to the range of available treatments for cardiac injury induced by skin burn.

• 아동학회지
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• 제28권5호
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• pp.221-232
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• 2007

The purpose of this study was to investigate the relationship among personal attributions of daycare center teachers in fields, social support, and teachers' burn-out. Data were collected by 228 teachers in day care center. To examine the relationship among personal attributions of daycare center teachers in fields, social support, and teachers' burn-out, it was used the scale of 'the tendency of attributions', 'social supports', and 'burn-out'. To analyze data, Pearsons' correlation and multiple regression were used. The results of this study were as followed. First, the score of daycare center teachers' personal attributions, social support, and teachers' burn-out were higher than the mean score. Second, internal and external variables were related to burn-out factors. Third, attribute disposition were related to teachers' burn-out. As a whole, teachers were tend to be in internal attributions, which led to a tendency to show positive reactions against burn-out. Forth, social supports were related to teachers' burn-out.

• 대한의생명과학회지
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• 제9권1호
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• pp.37-42
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• 2003

The present study was conducted to determine whether administration of heat extract of Lepidii Semen has an inhibitory effect on neutrophil-derived oxidative injury following dermal scald burn in rats. Acute lung injury was induced by scald burn (15% of TBSA) in rats. To identify acute edematous lung injury, protein concentrations and numbers of polymorphonuclear leukocytes were measured in bronchoalveolar lavage (BAL) at 5 h after skin burn. In addition, the level of lung KC (neutrophil chemoattractant cytokine) and activity of lung myeloperoxidase (MPO) were measured, and histopathological changes were observed as well. Lung weight and concentration of BAL protein, the index of lung injury, were clearly increased at 5 h postburn compared with those of sham-operated group. Administration of heat extract of Lepidii Semen after scald burn inhibited the production of KC in lung tissue and decreased the activity of lung MPO related to infiltration of neutrophils. In histopathological changes in lung tissue, infiltration of inflammatory cells and pulmonary edema induced by skin burn were decreased by administration of heat extract of Lepidii Semen after scald burn. These results suggest that Lepidii Semen may be an effective medical stuff for acute lung injury induced by skin burn.

• 대한화상학회지
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• 제23권2호
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• pp.37-41
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• 2020

Purpose: The purpose of this study was to investigate the usefulness of Procalcitonin (PCT) as a predictor of mortality in patients with burn sepsis, which is closely related to mortality. Methods: A retrospective study was conducted on 912 PCT patients diagnosed with burn sepsis in patients who survived fluid resuscitation for at least 3 days, aged 18 years or older who were admitted to Burn Intensive Care Unit (BICU) of Hallym University Hangang Sacred Heart Hospital from January 2008 to December 2018. Results: Compared with the surviving group, TBSA (31%:65%), Inhalation (59.66%:74.23%) and ABSI (8 points:12 points) were statistically significantly higher in the death group. Looking at the changes in PCT levels in each survival and death group from Week 1 to Week 4, there was a statistically significant difference in PCT levels in the survival and death groups each week (P<0.001). Although there were statistical differences between the survival and death groups in each state (P<0.001), there was no difference in PCT values for each state in both groups (P=0.090). Conclusion: In burn patients suspected of sepsis, the use of PCT is useful for predicting survival and death. It is necessary to conduct research based on prospective study through systematization of measurement standards and data from multiple institutions to increase the utilization of PCT through research that complements the limitations.