• Safety and Health at Work
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• 제8권4호
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• pp.386-392
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• 2017

Background: Fire service workers often implement multiple duties in the emergency conditions, with such duties being mostly conducted in various ambient temperatures. Methods: The aim of the current study was to assess the firefighters' physiological responses, information processing, and working memory prior to and following simulated firefighting activities in three different hot environments. Seventeen healthy male firefighters performed simulated firefighting tasks in three separate conditions, namely (1) low heat (LH; $29-31^{\circ}C$, 55-60% relative humidity), (2) moderate heat (MH; $32-34^{\circ}C$, 55-60% relative humidity), and (3) severe heat (SH; $35-37^{\circ}C$, 55-60% relative humidity). It took about 45-50 minutes for each firefighter to finish all defined firefighting activities and the paced auditory serial addition test (PASAT). Results: At the end of all the three experimental conditions, heart rate (HR) and tympanic temperature (TT) increased, while PASAT scores as a measure of information processing performance decreased relative to baseline. HR and TT were significantly higher at the end of the experiment in the SH ($159.41{\pm}4.25beats/min$; $38.22{\pm}0.10^{\circ}C$) compared with the MH ($156.59{\pm}3.77beats/min$; $38.20{\pm}0.10^{\circ}C$) and LH ($154.24{\pm}4.67beats/min$; $38.17{\pm}0.10^{\circ}C$) conditions (p < 0.05). There was no significant difference in PASAT scores between LH and MH (p > 0.05). Nonetheless, there was a measurable difference in PASAT scores between LH and SH (p < 0.05). Conclusion: These consequences demonstrate that ambient temperature is effective in raising the physiological responses following firefighting activities. It is therefore argued that further increase of ambient temperature can impact firefighters' information processing and working memory during firefighting activity.

• 생태와환경
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• 제49권4호
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• pp.375-384
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• 2016

Phytoplankton community is one of the important factors for the management of aquatic environment due to generation of varying toxins by harmful algal species. This study was performed to examine the phytoplankton community structure (PCS) in the midstream of Geum River (GR) from January 2014 to December 2015. The water sampling was performed in five stations on 2014, and three stations on 2015. Subsequently, the morphological identification was performed by microscopic observation in laboratory condition. As results, total 265 species were identified and it was comprised of 40.8% of Bacillariophyceae, 9.1% of Cyanophyceae, 44.5% of Chlorophyceae, and the others (4.9%). During the investigation period, total average standing crop of phytoplankton was $12,948cells\;mL^{-1}$, and it was comprised of $7,702cells\;mL^{-1}$ of Bacillariophyceae, $2,821cells\;mL^{-1}$ of Cyanophyceae, $2,121cells\;mL^{-1}$ of Chlorophyceae, and $305cells\;mL^{-1}$ of others. To verify which tributaries of upstream area influence on PCS of midstream of GR, the phytoplankton standing crops of two stations including Mihocheon (MH) and Gapcheon (GC) were examined on 2014, and compared to result of on 2015. The results were shown that the MH station had more similar phytoplankton standing crops with midstream of GR than GC station. The relationship between environmental parameters and phytoplankton dynamics was studied at the investigated station. As results, whereas water temperature and total phosphorus were represented the positive correlation, N/P ratio was remarkably exhibited negative correlation. From the results, it is suggested that the PCS of midstream of GR was more affected by MH station than GC station, and the changes of temperature, phosphorus concentration, and N/P ratio may be important factors on the PCS formation of midstream of GR.

• 대한의생명과학회지
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• 제28권3호
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• pp.170-177
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• 2022

In mountainous regions, wild herbs which can also be edible in nature for humans and animals possess a wide array of biologically diversified properties. It is because of the fact that due to the cold weather of mountains; they are enriched in certain kinds of phytochemicals such as anti-oxidants, anti-inflammatory and many more. One such kind of an herb is Aster scaber (AS) in Korean. It is a widely cultivated culinary herb in Korean peninsula and used as a side dish in Korean culinary cuisine. In view of its extensive use in cuisine, we geared to unravel the anti-oxidant and anti-inflammatory effects of AS in murine alveolar macrophage cell line (MH-S). 2,2'-Azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) assays revealed a dose dependent (7.8~1,000 ㎍/mL) inhibition of oxidation by AS 70% ethanol (ASE) extract as compared to Trolox and Ascorbic acid respectively. Nitric oxide assay (NO) showed a dose dependent decrease (5~40 ㎍/mL) in MH-S cells with ASE when stimulated with Coal Fly Ash (CFA). Moreover, this dose for NO reduction was also found to be least cytotoxic for cells as determined by cellular viability (MTT) assay. The gene expression of pro-inflammatory mediators (iNOS and COX-2) and cytokines (IL-6 and IL-1β) and were also dose dependently inhibited by ASE in MH-S cells through RT-PCR. Therefore, in light of these findings, AS exhibited a strong anti-oxidant and anti-inflammatory agent. These results also justify the extensive use of this mountainous herb in culinary practices for beneficial effects on human health.

• 대한수의학회지
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• 제63권3호
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• pp.27.1-27.9
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• 2023

Lespedeza cuneata (LC) is a perennial plant used in herbal medicine to treat numerous diseases, including prostatic hyperplasia, diabetes, early atherosclerosis, and hematuria. Reference collections of bioactive compounds of LC are crucial for the determination of their pharmacological properties. However, little is known regarding its anti-oxidative and anti-inflammatory effects in alveolar macrophage (MH-S) cells. This study examined whether LC can inhibit reactive oxygen species and Coal fly ash (CFA) induced inflammation in MH-S cells. The anti-oxidative effects of LC were evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays, anti-inflammatory effects were examined using nitric oxide (NO) assay, and cytotoxicity was analyzed using methyl thiazolyl tetrazolium assay. The expression of inflammatory cytokine genes was assessed through a reverse-transcription polymerase chain reaction. Our results revealed that LC exhibited high radical scavenging activity and a dose-dependent (7.8-1,000 ㎍/mL) inhibition of oxidation as compared to ascorbic acid and Trolox. It also inhibited CFA-induced NO production in MH-S cells. Moreover, it suppressed the CFA exposure-mediated expression of pro-inflammatory mediators and cytokines, including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin (IL)-1β, IL-6, and tumor necrosis factor-α. These results suggest that LC is a potent antioxidant and anti-inflammatory agent that can be useful as a nutraceutical product.

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 1999년도 제3회 총회 및 추계학술발표회
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• pp.8-8
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• 1999

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2001년도 춘계심포지움 및 학술발표회
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• pp.141-141
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• 2001

The arsenic resistance operon from pMH12 in Klebsiella oxytoca contains two regulatory genes. The first open reading frame for arsR extend up to 348 bp and has a translational product corresponding to a protein of 116 amino acid residue polypeptide with a molecular mass of 13 kDa. And the second ORF for arsD extend up to 360 bp and express a protein of 120 amino anid residue polypeptide with 13kDa. (omitted)

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2001년도 봄 학술발표논문집 Vol.28 No.1 (A)
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• pp.823-825
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• 2001

이동 에이전트는 자동으로 여러 새로운 호스트를 이동하여 사용자가 원하는 정보를 수집하거나 물품에 대한 구매 등을 할 수 있게 해주는 프로그램이다. 그리고 이러한 이동 에이전트를 사용함으로서 인터넷 환경, 특히 전자상거래에서의 많은 이익을 가져올 수 있다. 하지만 포괄적인 security framework의 부족으로 이동 에이전트의 보급과 사용에 많은 제한이 있다. 즉 악의적인 호스트에 의해서 에이전트의 state나 code가 위조될 수 있고 사용자에게 피해를 주게된다. 본 논문에서는 Multiple-Hop 환경에서의 이동 에이전트를 이용한 데이터 검색과 구매가 위조 및 변경되는 것을 감지하고 방지할 수 있는 프로토콜을 제안하였다.

• 한국통신학회논문지
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• 제18권8호
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• pp.1117-1127
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• 1993

전자우편서비스가 확대됨에 따라 정보 보호 문제가 중요한 현안으로 대두될 것이다. 이러한 필요성에 따라, MHS(Message Handling System) 시스템의 정보보호(Information Security) 서비스에 관련된 표준화(X.400 series)와 보안 서비스에 관련된 키 관리 메카니즘 표준화(X.509)출 분석하려다. 본 연구에서는 여러가지 보안서비스 중, 안전한 메시지 전송을 위해 1차적으로 메시지 비밀보장, 메시지 무결성, 발신처 인증 서비스를 위 한 SMP(Secure Message Protocol ) 프로토콜을 설계하여 UNIX BSD 4.3 시스템환경에서 구현하였다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권10호
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• pp.492-496
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• 2005

An electronic ballast with automatic identification between HPS and MH lamps is proposed in this paper. The behavior of the lamp impedance is studied at both cold-starting and warm-starting. Lamp identification is carried out by taking into account the rate of impedance changing at constant current driving mode just after ignition. The ballast consists of 8-bit microcontroller and LCC resonant inverter.

• 한국정보보호학회:학술대회논문집
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• 한국정보보호학회 1991년도 학술발표논문집
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• pp.155-164
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• 1991

컴퓨터가 널리 보급되고 정보통신 기술이 발전함에 따라 지리적으로 먼거리에 있는 사람에게 정보를 주고받을 수 있게 되었는데, 안전한 데이타의 송수신은 그 중요성이 더해가고 있다. 이런 시점에서 ISO가 OSI 환경에서 안전성 제공을 위해 IS 7498-2로 발표한 OSI Security Architecture에서는 5가지 안전성 서비스틀 제공하였다. 본 논문에서는 이들 중 이미 발생한 통신 사실을 부인할 수 없도록 하는 부인봉쇄 서비스를 제공할 수 있는 부인봉쇄 서비스 구현 모델을 MHS(Message Handling System)상에 설계하였으며, 구현방안을 제시하였다.