• 한국소음진동공학회논문집
• /
• 제22권9호
• /
• pp.825-829
• /
• 2012

The global warming caused the changes of our environment like an increasing tropical night phenomenon in the middle latitude areas. Especially, in Korea, the habitats of tropical Korean blockish cicada have changed from Jeju island located in Southern part of Korea to the whole of Korea because of the increasingly warming weather. The cicadas crying sound have been social problem because the tropical Korean blockish cicadas cry at middle of the night owing to the various outdoor lights. The cicada is positive phototaxis insect. So, the cicada is not cry at night. But if the outdoor light is very bright, then the cicada confuse the night as a day and start to cry. As a result, the cicadas crying noise has caused the resident living in downtown to an unpleasure and sleeplessness. In this research, we have measured three kinds of cicada singing noise at 16 points of urban area(Incheon, Gwangju, Busan, Gyeonggido Anyang). And then we analyzed the sound quality of the three kinds of cicada singing noise using by CADA-X signal process program. And we analyzed the acoustical characteristics by STFT(short time Fourier transform) which is a time-frequency analysis method. The characteristics of the cicada singing noise in terms of the sound quality and the time-frequency variation will be usefull to discover the relations between the human annoyance about the cicada singing noise and the acoustical characteristics.

• 설비공학논문집
• /
• 제27권12호
• /
• pp.633-638
• /
• 2015

This study evaluates the capacity of night purging in office buildings to reduce the cooling load. RTS-SAREK is used to estimate the performance of night purging on the steady state. To overcome steady state RTS program limitations, we added unsteady heat transfer equations. When the ACH (Air Change per Hour) increases, the wall temperature decreases in both the steady and unsteady states. The unsteady heat transfer rate is different from the steady transfer rate, which validates the unsteady calculation. When ACH is low, the heat transfer rate increases continuously with time. When ACH becomes higher, the heat transfer rate increases and decreases with time. When ACH is quite high, there exists a large difference in the heat transfer rate between the steady and unsteady calculations, which emphasizes the importance of the unsteady calculation.

• 한국항해항만학회지
• /
• 제34권5호
• /
• pp.305-309
• /
• 2010

예부선 산업의 발전은 예부선 교통량의 증가와 해상교통환경의 변화 등으로 인하여 해양사고가 꾸준히 증가하고 있는 추세이다. 예부선 해양사고의 주요 요인으로는 운항과실로 인한 충돌 접촉 사고가 전체의 70% 이상을 차지하고 있다. 이러한 운항과실 중에서도 예부선의 야간항해 시에 소형 선박들이 예선과 부선을 연결하고 있는 예인삭을 무분별하게 횡단함으로 인한 사고가 가장 큰 요인으로 조사되었다. 따라서 이 연구에서는 예부선의 야간항해 시에 소형 선박들이 예인삭을 쉽게 식별할 수 있도록 하는 여러 가지 방안을 제시하였다.

• 산업경영시스템학회지
• /
• 제23권57호
• /
• pp.1-10
• /
• 2000

The purpose of this paper is to propose a method of rest to reduce work load of night shift workers for night shift work. The experiment was carried out 10minutes preparing time, 45minutes first work, 10minutes first rest, 45minutes second work, 10minutes second rest between 2 and 4 o'clock that the lowest physiological function of workers. The methods of rest set up as four patterns (1) non-action rest (2) non-action rest + listening music (3) action rest + non-action rest, (4) action rest + non-action rest + listening music. For the measurements of experiment, heart rates(R-R interval), critical flicker fusion frequency(CFF), blood pressure, oral temperature, reaction time and error rates were considered as criteria for work performance. As a result, action rest + non-action rest and action rest + non-action rest + listening music were more effective to reduce work load additional work than non-action rest and non-action rest + listening music.

• 가정과삶의질연구
• /
• 제17권1호
• /
• pp.1-14
• /
• 1999

The purpose of this study were to examine relative contribution of personal.family.peer and school variables influencing runaway particularly the first-time rundaway and repeated one and to classify runaway types Runaway was significantly influenced by peer delinquency manic behavior family dysfunction school achievement night school depression family type and abuse by family members. First-time runaway was significantly influenced by peer delinquency family type depression abuse by family members night school Repeated runaway was significantly influenced by peer delinquency family dysfunction school achievement manic behavior and night school. Three runaway types were classified $\ulcorner$runaways from family crisis$\lrcorner$$\ulcorner$runaways dissatisfied with family$\lrcorner$ and $\ulcorner$funseekers$\lrcorner$.

• 한국지리정보학회지
• /
• 제17권1호
• /
• pp.35-49
• /
• 2014

서울과 주변을 포함하는 수도권에서 발생하는 열섬현상의 특성들을 정량적으로 이해하기 위하여 GIS 및 AWS 관측 자료들을 이용하여 여름과 겨울 야간 기온분포의 공간 경향 그래프를 작성하였다. 또한 기온 변동성에 영향을 미치는 요인들과 31개 AWS 지점들의 야간 평균기온과의 상관성을 분석을 하였다. 그 결과, 야간 평균기온(2004년~2011년) 최고지점과 최저지점의 차이는 여름 $4.5^{\circ}C$, 겨울 $7.1^{\circ}C$ 임을 확인하였다. AWS 지점들 주변의 국지적 지표특성과 기온과의 상관성 분석 결과, 지점별 야간 평균 기온과 반경 1km 이내의 인공피복의 상관계수가 여름(0.84)과 겨울(0.78) 모두에서 높게 나타나 지표면 피복이 중규모적인 도시 열환경 관리에 있어 다른 요인들보다 더 큰 영향을 주는 요인임을 확인하였다. 한편 수도권 야간기온에 대한 회귀모형을 변수선택법을 이용하여 개발한 결과 1km 규모에서 보다 200m 규모에서 상세한 지표특성 변수가 선택됨을 알 수 있었는데, 규모에 따른 모형의 설명력에는 큰 차이가 없었다. 따라서 200m 정도의 상세한 지표특성 자료를 이용하는 기후분석 모델의 구현이 가능함을 알 수 있었으며, 모델의 설명력은 1km 수준으로 분석하였을 때와 비슷한 수준인 57%(겨울)~72%(여름)이었다.

• 생물환경조절학회지
• /
• 제20권4호
• /
• pp.326-332
• /
• 2011

본 연구는 주요 봄배추 품종에 대하여 야간 저온처리가 생육 및 추대에 미치는 영향을 평가하여 봄배추 육묘 시 안정 환경관리의 기준을 설정하고자 수행하였다. 시험에는 '춘광' 등 주요 봄배추 7품종을 이용하였으며 생육상을 이용하여 야간에 $5^{\circ}C$ 및 $10^{\circ}C$의 저온처리를 실시하였다. 처리시점은 파종 후 5, 10 및 15일째부터, 처리기간은 각 처리시작 시점부터 5, 10 및 15일간으로 각각 조합 처리한 후 포장에서의 생육 및 추대 여부를 조사하였다. 시험에 사용한 모든 품종에 있어서 최대 $5^{\circ}C$에서 15일간의 야간 저온처리에 의하여 유묘생육은 크게 저하하였으나 재배기간 동안 추대는 일어나지 않았으며 정식 90일 후 정상적인 수확이 가능하였다. '춘광' 품종에 대한 육묘기 야간 저온처리 개시 시점과 처리기간의 복합 처리 결과, 낮은 온도조건으로 어린식물체의 상태에서 처리기간이 길어짐에 따라 묘 생체중이 대조구에 비해 최대 59.3%까지 크게 감소되었다. 반면 저온처리 후 생육이 극도로 억제된 묘는 정식 후 생육이 다시 회복되어 수확시 생체중은 대조구 대비 72.3~110%의 범위를 나타내어 모든 처리구에서 정상적인 수확이 가능하였다. 또한 $5^{\circ}C$ 또는 $10^{\circ}C$에서 최대 15일간의 육묘기 야간저온 처리에 의한 추대 현상은 관찰되지 않았다. 본 연구를 통해 봄배추 주요 품종에 대한 육묘기 야간 저온이 생육에 미치는 영향은 제한적으로 나타났다. 육묘기간 동안 단기간 $5^{\circ}C$ 이하의 저온에 노출된 경우에도 주간의 적정한 온도관리와 포장에서의 기후조건에 따라 추대를 지연시키거나 방지시킬 수 있을 것으로 생각된다.

• 한국환경과학회지
• /
• 제6권6호
• /
• pp.697-709
• /
• 1997

Sequencing Batch Reactor(SBR) experiments for organics and nutrients removal have been conducted to find an optimum anaerobic/anoxic/aerobic cycling time and evaluate the applicability of oxidation-reduction potential(ORP) as a process control parameter. In this study, a 61 bench-scale plant was used and fed with night-soil wastewater in K city which contained TCODcr : 10, 680 mg/l, TBm : 6, 893 mg/l, $NH_4^+-N$ : 1, 609 mg/l, $PO_4^{3-}-P$ : 602 mg/l on average. The cycling time In SBRs was adjusted at 12 hours and 24 hours, and then certainly included anaerobic, aerobic and inoxic conditions. Also, for each cycling time, we performed 3 series of experiment simultaneously which was set up 10 days, 20 days and 30 days as SRT From the experimental results, the optimum cycling time for biological nutrient removal with nlght-soil wastewater was respctively 3hrs, 5hrs, 3hrs(anaerobic-aerobic-anoxic), Nitrogen removal efficiency was 77.9%, 77.9%, 81.7% for each SRT, respectively. When external carbon source was fed in the anoxic phase, ORP-bending point indicating nitrate break point appeared clearly and nitrogen removal efficiency increased as 96.5%, 97.1%, 98.9%. Phosphate removal efficiency was 59.8%, 64.571, 68.6% for each SRT. Also, we finded the applicability of ORP as a process control parameter in SBRs.

• 부모자녀건강학회지
• /
• 제3권2호
• /
• pp.1-17
• /
• 2000

The purpose of this study was to recognized the sleep activity patterns of the normal infants in Korea. The subject were 41 normal infants who were below 8 weeks old and were born in Taegu city and Kyungbuk province. The measuring instrument the sleep activity was NCASA translated by the Korean-parent-child Health Academic Association. The data that were collected from April, 18 1999 to January 1, 2000 were analysed by the SPSS 7.5 program. The results of the study was summarized as follow; 1) The mean amount of total sleeping hours per day was decreased from $16.27{\pm}1.96$ hr at the 1st week, to $15.19{\pm}2.39$ hr at the 2nd week, to $13.66{\pm}2.40$ hr at the 3 week but increased to $16.55{\pm}5.77$ hr at the 4-8 week after birth. 2) The mean frequency of feeding was increased to $9.43{\pm}2.79$ times at the 3rd week but decreased to $7.55{\pm}1.23$ times at the 4-8th week after birth. 3) The regularity of day time sleep was decreased from 50.00% to 19.79% and that of night time sleep was increased from 51.79% to 72.92%. 4) The regularity of feeding was increased from 30.42% at the 1st week to 50.07% at the 2nd week but decreased 26.34% at the 4-8th week after birth. 5) The longest period of day time sleep was decreased to $2.39{\pm}0.42$ hr at the 3rd week but increased $2.47{\pm}0.69$ hr at the 4-8th week after birth. The longest period of night time sleep was decreased to $2.58{\pm}0.67$ hr at the 2nd week but increased to $3.00{\pm}1.32$ at the 3rd week and $4.30{\pm}1.16$ hr at the 4-8th week after birth. 6) At the 1st week, the 2nd week, the 3rd week after birth, the frequency of day time feeding was positively correlated with the frequency of night time feeding($R_{1week}=0.948^{**}$, $R_{2week}=0.927^{**}$, $R_{3week}=0.779^{**})$. At the 4-8th week after birth, the frequency of night time feeding was negatively correlated with the amount of night time sleep ($R_{4week-8week}=0.875^{*}$). On the basis of above findings, the following is suggested; It is need a longitudinal and transcultural study which are designed for children's sleep and feeding.

• 한국환경과학회지
• /
• 제17권9호
• /
• pp.1053-1068
• /
• 2008

This study aims to produce fundamental database for Environment Impact Assessment by monitoring vertical structure of the atmosphere due to the mountain valley wind in spring season. For this, we observed surface and upper meteorological elements in Sangin-dong, Daegu using the rawinsonde and automatic weather system(AWS). In Sangin-dong, the weather condition was largely affected by mountains when compared to city center. The air temperature was low during the night time and day break, and similar to that of city center during the day time. Relative humidity also showed similar trend; high during the night time and day break and similar to that of city center during the day time. Solar radiation was higher than the city, and the daily maximum temperature was observed later than the city. The synoptic wind during the measurement period was west wind. But during the day time, the west wind was joined by the prevailing wind to become stronger than the night time. During the night time and daybreak, the impact of mountain wind lowered the overall temperature, showing strong geographical influence. The vertical structure of the atmosphere in Dalbi valley, Sangin-dong had a sharp change in air temperature, relative humidity, potential temperature and equivalent potential temperature when measured at the upper part of the mixing layer height. The mixing depth was formed at maximum 1896m above the ground, and in the night time, the inversion layer was formed by radiational cooling and cold mountain wind.