• 한국군사과학기술학회지
• /
• 제10권3호
• /
• pp.62-70
• /
• 2007

Most design temperature of environmental test in korea is based on the standard of Department of Defense. There are few studies to establish temperature standard. Besides the representative environmental test guide 'MIL-STD-810F' encourage to tailor to generate the most relevant test data possible and to test to make a match of test environment with operational environment. Under these circumstances, it is irrational to comply with baseless daily cycle. Thus the study about design method of test temperature is essential. So, the daily cycles to be appropriate to the Korean peninsula was presented in this study. And this research shows how to derive two main element, frequency-of-occurrence and daily maximum (minimum) temperature in daily cycles, in case we can not find the daily cycle.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2001년도 추계학술대회 논문집 전력기술부문
• /
• pp.371-373
• /
• 2001

In this paper, we present 2-step load cycle for daily load curve of up to and including 100kVA distribution transformer in domestic. Daily load patterns are classified by two methods dependent upon possession information. In case we possess daily load profiles make use of K-mean algorithm and in case we have not daily load profiles, make use of customer information of KEPCO. As the parameters of the load pattern classification, we use are daily load profiles and customer information of each distribution transformers. Data management system is used for NT oracle. We can present peak load magnitude, initial load magnitude and peak load duration for daily load patterns by 2-step load cycle for daily load curve of up to and including 100kVA distribution transformer in domestic. We think that this paper contributes to enhancing the distribution transformer overload criterion.

• 한국수소및신에너지학회논문집
• /
• 제22권5호
• /
• pp.663-670
• /
• 2011

Under a daily photoperiod of 14h light and 10h dark synchronization of cell cycle in Korean Cyanothece spp. strains and $Synechococcus$ sp. strain Miami BG043511 was analyzed as to be applicable to enhanced hydrogen production. For all strains peaks of double cell were observed during the light period of a daily cycle. Peaks of maximal cell size measured by a coulter counter appeared at the peak of double cells observed under light microscope reconfirming the synchronization of daily cell cycle. The cell cycle synchronization became weakened within two days when treated with continuous illumination. Rapid detection of the peak time of double cell percentage by coulter counters may contribute to quasi-realtime feedback control for efficient production of photobiological hydrogen by unicellular cyanobacterial strains.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• 제7권1호
• /
• pp.52-60
• /
• 1996

본 연구는 월경전기에 불편감이 있다고 응답한 230명의 여고생을 대상으로 전향적인 매일 평가서를 사용하여 월경주기에 따른 신체적, 기분, 행동변화의 양상을 보고자 하였다 '월경전 불쾌기분장애'로 확인된 군과 전체대상군 모두에서 후기황체기에 신체적 , 심리적 증상들이 뚜렷한 악화를 보이기 시작하여 월경이 시작되면서 증상의 최고치를 나타냈으며, 월경시작4일째에 급격한 감소를 보였다. 또한 월경주기중에서 특히 월경기때에 보다많이 신체적인 불편감을 경험하고 있고, 이때 월경기간이 길수록 불편감이 큰 것으로 보여진다. 이러한 양상들은 젊은 여성의 월경전기 변화 양상을 대표할 수는 없으나, 본 대상군이 여고생임을 감안할 때 우리나라 청소년의 월경주기에 따른 고유한 증상의 변화양상을 보여주는 것이라고 할 수 있겠다.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2003년도 학술발표논문집
• /
• pp.447-450
• /
• 2003

It is important to calculate runoff, percolation and evapotranspiration in process hydrological cycle. Especially, a evaportranspiration in watershed has a very important effect on hydrological cycle. In the study, the watershed evapotranspiration was calculated by the water balance and a daily evaportanspiration coefficient(CE) was calculated by the modified Beken's formula.

• 한국대기환경학회:학술대회논문집
• /
• 한국대기환경학회 2000년도 춘계학술대회 논문집
• /
• pp.317-318
• /
• 2000

오늘날 우리는 문명이 발달하고 고도로 산업화된 사회의 구성원으로써 살아나가고 있다. 그러나 우리의 삶을 영위하는 과정에서 생긴 각종 환경오염에 노출되고 있어서 이로 인하여 우리의 삶의 질이 저하되기도 한다. 여러 가지 오염물질이 대기중에 가득한 가운데서 순간순간 숨을 쉬며 살아가는 우리 인간은 호흡기나 피부를 통하여 각종 대기오염물질에 직·간접적으로 노출되고 있는 실정이다. 이중 특히, 벤젠이나 톨루엔과 같은 휘발성유기화합물(Volatile Organic Compounds : VOCs)은 실내 생활이나 작업, 야외활동, 또 여러 삶의 과정에서도 노출되고 있는 듯 하다. (중략)

• 한국대기환경학회:학술대회논문집
• /
• 한국대기환경학회 2000년도 추계학술대회 논문집
• /
• pp.283-284
• /
• 2000

석유화학, 비철금속공단, 조선 및 기계공단 등과 같은 대형 산업단지를 가진 울산지역의 대기오염은 타 지역에 비하여 꽤 높은 것으로 보고되고 있다. 또한 울산지역은 인구가 백만이 넘는 대형도시이고, 사람과 각종 공단 생산제품을 수송하기 위한 교통밀도도 꽤 높으므로 많은 양의 휘발성 유기화합물(Volatile Organic Compounds : VOCs)이 배출되고 있다. 흔히 VOC는 대류권 오존 농도의 전구체로서 역할을 하여 대류권 오존농도 감소를 위한 연구가 활발히 진행되고 있다. (중략)

• Journal of Astronomy and Space Sciences
• /
• 제29권2호
• /
• pp.103-113
• /
• 2012

The ButterStar Observatory at the Dongducheon High School has been working for photographic observations of the Sun since October 16, 2002. In this study, we observed the Sun at the ButterStar observatory for 3,364 days from October 16, 2002 to December 31, 2011, and analyzed the photographic sunspot data obtained in 1,965 days. The correction factor $K_b$ for the entire observing period is 0.9519, which is calculated using the linear least square method to the relationship between the daily sunspot number, $R_B$, and the daily international relative sunspot number, $R_i$. The yearly correction factor calculated for each year varies slightly from year to year and shows a trend to change along the solar cycle. The correction factor is larger during the solar maxima and smaller during the solar minima in general. This implies that the discrepancy between a relative sunspot number, R, and the daily international relative sunspot number, $R_i$, can be reduced by using a yearly correction factor. From 2002 to 2008 in solar cycle 23, 35.4% and 64.6% of sunspot groups and 35.1% and 64.9% of isolated sunspots in average occurred in the northern hemisphere and in the southern hemisphere, respectively, and from 2008 to 2011 in solar cycle 24, 61.3% and 38.7% of sunspot groups and 65.0% and 35.0% of isolated sunspots were observed, respectively. This result shows that the occurrence frequency for each type of sunspot group changes along the solar cycle development, which can be interpreted as the emerging and decaying process of sunspot groups is different depending on the phase of solar cycle. Therefore, it is considered that a following study would contribute to the efforts to understand the dependence of the dynamo mechanism on the phase of solar cycle.

• 대한간호학회지
• /
• 제50권1호
• /
• pp.147-157
• /
• 2020

Purpose: This descriptive study aimed to identify the menstrual cycle characteristics and premenstrual syndrome (PMS) prevalence in Korean young adult women using the retrospective and prospective Daily Record of Severity of Problems (DRSP). Methods: In the first stage, participants included 151 nursing students studying in a university located in Seoul. Data were collected from April 20 to June 2, 2017, using the questionnaire on menstrual characteristics, pictorial blood assessment chart, and retrospective DRSP. In the second stage, participants included 17 students with PMS, based on the screening conducted in the first stage. Data were collected using the prospective DRSP from May 29 to 2 September 2, 2017. Results: Of the study sample, 104 participants (68.9%) had regular periods. Those with regular periods had 11.97 periods annually with a menstrual cycle of 29.38 days and a period duration of 5.72 days. Fifty-five participants (37.4%) showed menorrhagia. Sixty-four participants (42.4%) were found to have PMS based on their retrospective DRSP. When the ratio of women (52.9%) with PMS shown in the prospective DRSP was used as a positive predictive value, the estimated PMS prevalence was 22.4%. Conclusion: This study provides clinically significant PMS prevalence among Korean young adult women, positive predictive value of the retrospective DRSP, and valid data to basically understand the menstrual cycle characteristics experienced by these women.

• 한국융합학회논문지
• /
• 제10권12호
• /
• pp.447-451
• /
• 2019

본 연구는 일상생활 속 개인적 특성에 따른 안경렌즈 흠집과 교체주기를 조사해 보고자 하였다. 본 연구에 자발적으로 참여한 58명을 연구대상자로 하였으며, 안경착용 시 속눈썹의 안경렌즈 접촉 여부, 1일 안경렌즈 닦는 횟수, 안경렌즈를 닦는 종류에 따른 안경렌즈 교체주기를 분석하였다. 통계분석은 X² 검정과 Fisher의 정확도 검정을 하였다. 안경렌즈의 평균 교체주기는 남자보다 여자가 긴 것으로 나타났으며, 속눈썹이 안경렌즈에 접촉되는 경우, 안경수건이 아닌 휴지나 옷 등을 사용하여 안경렌즈를 닦는 경우에 안경렌즈 교체주기가 유의하게 짧게 나타났다. 안경렌즈의 코팅막은 속눈썹이나 일상생활 속의 사소한 부주의등과 같이 융복합적 영향으로 손상이 발생할 수 있다는 것을 확인한 바, 이 결과에 대한 후속연구를 이어가고자 한다.