• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 추계학술논문발표회 논문집
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• pp.310-315
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• 2008

The objective of design for a post flash-over fire is contain the fire and prevent structural collapse, as necessary to meet the performance requirements. In the post flash-over phase of a fire all of the combustible objects in the compartment are burning and the heat release rate is limited either by the fuel surface area or the available air supply. So for the PBD situations, the process of evaluation method for fire phenomena is very important. It is the aim of this study to investigate and analyze the evaluation method of structural fire resistance in Japan.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.305-310
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• 2003

Recently, gypsum boards are widely used as interior finishing boards for constructions because of their features of absorbing heats and little temperature rising at the early stage of fire. Therefore, in this research, basic data were suggested to secure fireproof stability by investigating interior processing features, which change together with the backside temperature of test materials from Flash Over (within 30 minutes after firing), at which temperature reaches its highest point, to survey the features of materials due to rising temperature in the chase of gypsum boards (general and fireproof gypsum boards)

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1856-1858
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• 2002

As the statistical data, the most of electrical shock accidents have been caused by human errors including those of mistake, carelessness, and so on during normal condition. But, there are currently no international standards for the determination of withstand distance to ensure safety of personnel form 22.9 kV electrical power facilities during their normal operation. Therefore, this paper describes the characteristics of flash-over voltage by moisture variation to establish the distance clearances in terms of electrical safety.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제15권7호
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• pp.515-519
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• 2009

센서 노드의 활용 분야가 점차 다양화되는 추세이므로 활용 분야에 적합한 다양한 데이터 수집 방법이 요구된다. 데이터의 실시간 감시가 불필요한 경우 수집과 동시에 전송을 수행하는 현재의 데이터 수집 방법은 불필요한 전력 소모 및 데이터 손실을 발생시킬 수 있다. 데이터를 수집한 노드가 데이터를 저장하고 질의에 의해 필요한 데이터를 획득하는 새로운 방법이 요구된다. NAND 플래시는 에너지 효율성이 좋고 대용량화가 쉬워 앞으로의 센서 노드용 저장소로 적합하다. 센서 노드는 4${\sim}$10 KByte의 적은 메모리를 지원하고 NAND 플래시는 덮어쓰기가 불가하고 쓰기 제한이 있어 효율성이 뛰어난 파일 시스템의 구축은 어렵다. 본 논문은 센서 노드 환경에서 대용량 NAND 플래시 파일 시스템의 설계에 대해 논한다. 파일 시스템은 전송 비용을 줄여 보다 장시간 동안의 데이터 수집을 가능하게 한다. 앞으로 다양한 분야에 적용되어 센서 네트워크 환경에서 핵심 구실을 할 것으로 예상한다.

• 한국전기전자재료학회논문지
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• 제25권2호
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• pp.100-104
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• 2012

Fin-type SONOS (silicon-oxide-nitride-oxide-silicon) flash memory has emerged as novel devices having superior controls over short channel effects(SCE) than the conventional SONOS flash memory devices. However despite these advantages, these also exhibit undesirable characteristics such as corner effect. Usually, the corner effect deteriorates the performance by increasing the leakage current. In this paper, the corner effect of fin-type SONOS flash memory devices is investigate by 3D Process and device simulation and their electrical characteristics are compared to conventional SONOS devices. The corner effect has been observed in fin-type SONOS device. The reason why the memory characteristic in fin-type SONOS flash memory device is not improved, might be due to existing undesirable effect such as corner effect as well as the mutual interference of electric field in the fin-type structure as reported previously.

• 한국정보과학회논문지:시스템및이론
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• 제27권6호
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• pp.567-582
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• 2000

본 논문은 로그파일시스템의 원리를 바탕으로 플래시메모리 저장시스템에 적합한 플래시메모리 공간 관리 방법을 제안한다. 플래시메모리는 비휘발성, 빠른 입출력 속도 등의 장점을 지니고 있지만, 제자리 덮어쓰기(in-place update)가 불가능하고 메모리 셀에 대한 쓰기(write) 횟수가 제한되는 단점이 있다. 이러한 특성은 플래시메모리를 저장 매체로 사용할 때 기존의 저장 매체 관리 방법과는 다른 방법을 요구하게 된다. 본 논문은 자유 공간유지를 위해 필요한 클리닝 메커니즘의 연산 비용을 낮추면서 동시에 저장공간이 전체적으로 균등하게 사용될 수 있도록 하는 사이클 평준화 기법을 제안한다. 제안된 방법은 특히 메모리 활용도와 로컬리티가 높을 때 좋은 성능을 보인다. 클리닝 메커니즘은 자주 접근되지 않는 COLD데이타를 그렇지 않은 데이타와 격리시킴으로써 그 효율이 향상되었으며, 사이클 평준화는 사용 횟수간의 최대 차이가 하드웨어적인 오차를 벗어나지 않는 수준까지 이루었다. 실험을 통해 제안된 방법은 비교 기준으로 삼은 직관적 방법(greedy policy)에 비해 사이클 평준화가 잘 이루어진 상태에서 최대 35%정도의 클리닝 비용 절감 효과를 보였다.

• 한국정보통신학회논문지
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• 제16권5호
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• pp.885-891
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• 2012

해상용 등명기의 동기 점멸은 해상에서 선박이 운항할 때, 다른 위험 표시기의 점등 패턴과 구분하여 선박의 안전한 운항을 지원한다. 일반적인 해상용 등명기의 점등기법은 낮과 밤을 감지하여 정해진 점등 규약에 따라 점등하는 방식으로 시간이 지남에 따라 등명기들의 시간 오차가 발생하여 등명기 전체의 동기 점멸이 이루어지지 못하고 있다. 이러한 문제를 해결하기 위하여 본 연구에서는 GPS의 위성시간을 기준으로 하여 모든 등명기들이 개별적으로 동기시간을 일정하게 맞추는 동기식 점등기법을 사용한 정전류방식의 해상용 LED 등명기를 설계하였으며, LED등명기 내부의 제한되고 밀폐된 공간에서 효율적인 방열성능을 갖는 방열방법을 제시하였다.

• 한국전기전자재료학회논문지
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• 제15권10호
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• pp.831-837
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• 2002

Scaled SONOS transistors have been fabricated by 0.35$\mu\textrm{m}$ CMOS standard logic process. The thickness of stacked ONO(blocking oxide, memory nitride, tunnel oxide) gate insulators measured by TEM are 2.5 nm, 4.0 nm and 2.4 nm, respectively. The SONOS memories have shown low programming voltages of ${\pm}$8.5 V and long-term retention of 10-year Even after 2 ${\times}$ 10$\^$5/ program/erase cycles, the leakage current of unselected transistor in the erased state was low enough that there was no error in read operation and we could distinguish the programmed state from the erased states precisely The tight distribution of the threshold voltages in the programmed and the erased states could remove complex verifying process caused by over-erase in floating gate flash memory, which is one of the main advantages of the charge-trap type devices. A single power supply operation of 3 V and a high endurance of 1${\times}$10$\^$6/ cycles can be realized by the programming method for a flash-erased type EEPROM.

• 대한한방내과학회지
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• 제38권5호
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• pp.576-582
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• 2017

Objectives: Hormone replacement therapy may relieve many symptoms of menopause; however, hormone replacement therapy may increase the risk of breast cancer, stroke, and dementia. This case study describes the effect of Hoechunboeum-tang on the menopausal disorder of hot flashes, which has been well documented as a cause of distress to patients undergoing menopause. Methods and Results: Two female patients suffering from severe hot flashes related to menopausal disorders were administered the herbal medicine, Hoechunboeum-tang. Measurements included hot flash frequency over a 24 hour period, hot flash severity (visual analogue scale), and hot flash-related daily interference and were recorded during the last week before herbal medicine and again after 7 and 15 days of herbal treatment. The patients were asked about their hot flash symptoms 6 months later and both reported that the symptoms had been successfully reduced after herbal treatment and were still reduced after 6 months. Conclusions: Hoechunboeum-tang could have a beneficial effect on menopausal disorder with hot flashes.

• International Journal of Computer Science & Network Security
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• 제21권5호
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• pp.23-30
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• 2021

In recent years, hazardous flash flooding has caused deaths and damage to infrastructure in Saudi Arabia. In this paper, our aim is to assess patterns and trends in climate means and extremes affecting flash flood hazards and water resources in Saudi Arabia for the purpose to improve risk assessment for forecast capacity. We would like to examine temperature, precipitation climatology and trend magnitudes at surface stations in Saudi Arabia. Based on the assessment climate patterns maps and trends are accurately used to identify synoptic situations and tele-connections associated with flash flood risk. We also study local and regional changes in hydro-meteorological extremes over recent decades through new applications of statistical methods to weather station data and remote sensing based precipitation products; and develop remote sensing based high-resolution precipitation products that can aid to develop flash flood guidance system for the flood-prone areas. A dataset of extreme events has been developed using the multi-decadal station data, the statistical analysis has been performed to identify tele-connection indices, pressure and sea surface temperature patterns most predictive to heavy rainfall. It has been combined with time trends in extreme value occurrence to improve the potential for predicting and rapidly detecting storms. A methodology and algorithms has been developed for providing a well-calibrated precipitation product that can be used in the early warning systems for elevated risk of floods.