• Title/Summary/Keyword: 일출전

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동지나해의 초음파 산란층에 관한 연구 ( 1 ) ( Acoustic Scattering Layers in the East China Sea ( 1 ) )

  • Lee, Dae-Jae;Shin, Hyeong-Il;Park, Jung-Hee
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.26 no.1
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    • pp.14-19
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    • 1990
  • This paper describes on the characteristics of the acoustic echoes from the scattering layers by the aggregation of marine organisms which was measured by using a 50kHz echo sounder on board of the training ship SAEBADA belong to National Fisheries University of Pusan during the summer, 1989 in the East China Sea. A data acquisition system was used to record digitally the envelope of the echoes and the frequency distribution of echo amplitudes on the whole water column was examined as a function of time during the sunrise and sunset periods. Acoustic data showed that the abundance distribution of marine organisms according to depth in the servery area changed with time and that the organisms were most active during the twilight of morning, and the echo strength on the water column or scattering layer was also strongest during this time. Additional results of this survey suggest that other interest, such as the relationship between environmental conditions and biomass depth distribution, could be also investigated in hydroacoustic method.

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Appropriate Root-zone Temperature Control in Perlite Bag Culture of Tomato during Winter Season (저온기 토마토 펄라이트 자루재배시 최적 근권온도 조절 방법)

  • Kim, Sung-Eun;Sim, Sang-Youn;Lee, Sang-Don;Kim, Young-Shik
    • Horticultural Science & Technology
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    • v.28 no.5
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    • pp.783-789
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    • 2010
  • The effective method for heating root-zone during winter season was studied in the aspects of growth, yield and economics for tomato ($Solanum$ $lycopersicum$) in perlite bag culture. There were four root-zone heating treatments: two hours heating from one hour before to one hour after sunrise, four hours from two hours before to two hours after sunrise, 15 hours after sunset, and no heating. The growth characteristics of the upper parts of plants were not significantly different among the treatments, but root volume increased with longer heating of the root zone. The Plant Development Index, using stem diameter and the length between growing tip and the upper flowering truss, showed relation between yield per cluster and growth pattern. The treatment heating for four hours was the most economic in terms of growth and yield of tomato.

Effects of Supplemental Lighting on Growth and Yield of Sweet Pepper (Capsicum annuum L.) in Hydroponic Culture under Low Levels of Natural Light in Winter (동계시설내 보광이 수경재배 착색단고추(Capsicum annum L.)의 생육에 미치는 영향)

  • Kim, Yong-Bum;Bae, Jong-Hyang;Park, Me-Hea
    • Horticultural Science & Technology
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    • v.29 no.4
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    • pp.317-325
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    • 2011
  • This study was conducted to examine the effect of supplemental lighting on the growth and yield of hydroponically grown sweet pepper (Capsicum annuum L. cv. sprit) under low levels of natural light in winter. The plants were treated with natural light only (control), 3-hour supplemental lighting before sunrise, after sunrise and after sunset with high pressure sodium (HPS, 400W). As the result of these three treatments, the supplemental lighting promoted photosynthesis in the low light intensity condition and particularly photosynthesis was more active right after sun rise in the morning, 1.5-$3.0{\mu}molCO_2{\cdot}m^{-2}{\cdot}s^{-1}$ comparing to those of supplemental lighting after sunset, 0.5-$1.5{\mu}molCO_2{\cdot}m^{-2}{\cdot}s^{-1}$. Transpiration rate and stomatal conductance sharply increased with supplemental lighting after sunrise then they decreased again after turning the lights off. Stomatal size was observed $32.2{\mu}m^2$ after supplemental lighting, whereas the size of the natural light was almost closed at $7.7{\mu}m^2$. The average plant height of sweet papper cv. spirit was 185 cm before sunrise, 188 cm after sunrise and 208 cm after sunset with supplemental lighting for 3hours while the control was 171 cm. With supplemental lighting a better number of fruit set per plant was measured 4.3 before and after sunrise, 3.7 after sunset but 2.6 in the control. Interestingly, there were no significant differences in the sugar content ($^{\circ}Brix$) degree between treatment of supplemental lighting, whereas slight differences between seasons were seen. The marketable fruit yield of sweet pepper (cv. spirit) was $116.0kg{\cdot}ha$ with supplemental lighting, whereas the control (natural light only) was $75.8kg{\cdot}ha$. Despite of spending electricity and depreciation cost, the economic analysis showed net income with supplemental lighting after sunrise was 51% higher than control treatment in cv. spirit.

Effects of Light Pollution and Environmental Factors on Dawn Song Initiation Time of Great Tit, Parus major (빛공해 및 환경요인에 의한 박새의 새벽 Song 시작시간 영향 연구)

  • Ki, Kyong-Seok;Cho, Woo
    • Korean Journal of Environment and Ecology
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    • v.28 no.4
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    • pp.411-418
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    • 2014
  • This study seeks to identify the effects of light pollution and environmental factors on Great Tits(Parus major) bird's chirping at dawn. For this research, the campus of Sanji University, Wonju, South Korea was selected as the area with light pollution and the western forest of the Chiaksan National Park was chosen as the natural area herein. The Recording period was between March 26th and May 30th, 2014. As a result of analyzing the chirping time according to light pollution, it was found that the light pollution area clearly showed earlier chirping time than the natural area (p<0.05). Great Tits(P. major) normally start their first chirping before sunrise and in most of the days under investigation of this research, those in Sanji University started to chirp earlier. This faster chirping time seems to improve the chance for the female birds to mate with immature males thus, baby birds hatch earlier than the appropriate breeding season and results in the lack of feed resources. The correlation between Great Tits'(P. major) dawn chirping and environmental factors were investigated herein including the time of sunrise, civil twilight, navigation twilight, astronomical twilight, average temperature, highest temperature, lowest temperature, time of moonrise and cloudiness. The first chirping time of wild birds in the day was found to have correlations with all of the environmental factors excluding the time of moonrise and cloudiness. Great Tits(P. major) started their first chirping before sunrise when the day started to break around civil twilight. Along with the earlier sunrise and higher air temperature, their dawn chirping time was also quickened. The time of moonrise and cloudiness did not show a correlation and further follow-up studies will be necessary in this regard.

Analysis of Temperature Changes in Greenhouses with Recirculated Water Curtain System (순환식 수막하우스의 수온에 따른 플라스틱 온실 내 온도변화 분석)

  • Kim, Hyung-Kweon;Jeon, Jong-Gil;Paek, Yee;Pyo, Hee-Young;Jeong, Jae-Woan;Kim, Yong-Cheol
    • Journal of Bio-Environment Control
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    • v.24 no.2
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    • pp.93-99
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    • 2015
  • The purpose of this study was to determine the appropriate temperature for water curtain in greenhouses equipped with recirculated water curtain system. The study analyzed the changes in air temperature in non-heated greenhouses for strawberry cultivation based on outdoor temperature, water curtain temperature and night time. Three greenhouse units were used for this study: The first unit was assigned as a control (no water curtain system), two other greenhouses were equipped with recirculated water curtain system with water curtain temperatures of $10^{\circ}C$ and $15^{\circ}C$, respectively. Analysis showed that the indoor temperatures were directly correlated with the outdoor temperature in all experimental greenhouses. Heat insulating effect of $15^{\circ}C$ water curtain was increased by $1.3^{\circ}C$ compared to that in $10^{\circ}C$ water curtain system. The $15^{\circ}C$ water curtain treatment showed the highest average temperature and less temperature variation in comparison with control and $10^{\circ}C$ water curtain treatment. To maintain indoor temperature at $5^{\circ}C$, water curtain temperature of $10^{\circ}C$ was suitable when outdoor minimum and average temperatures were -1.3 and $1.5^{\circ}C$, and water curtain temperature of $15^{\circ}C$ was suitable when outdoor minimum and average temperatures were -4.7 and $-0.2^{\circ}C$, respectively. The highest temperature in greenhouses according to measurements in different periods of night time was observed after sunset (18:30-20:30), and the lowest temperature before sunrise (05:00-07:00). Water curtain maintained a target indoor temperature by acting as a layer of heat transfer insulator which decreased heat loss from greenhouses. Therefore, water temperature in recirculating water curtain systems should be determined by considering outdoor temperatures, changes in temperature at different periods of night time, and cultivated crop.

A Study on the Sunshine Environment Around Urban Redevelopment Area Using a GIS Data (GIS 자료를 활용한 도시 재개발 주변 지역의 일조 환경 분석)

  • Kang, Jung-Eun;Park, Soo-Jin;Kim, Jae-Jin
    • Korean Journal of Remote Sensing
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    • v.34 no.5
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    • pp.749-762
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    • 2018
  • In this study, the changes of the sunshine environment due to the construction of buildings were analyzed by season. Using a geographic information system (GIS) data, the topography and the buildings were constructed around Pukyong National University (PKNU) in Busan. The numerical model was performed for a week in each season, before and after the construction of buildings. Even before the construction of the high-rise building complex, the area of sunshine block is wide due to the apartment complex located in the southeast of the PKNU campus and the mountain in the south. After the construction, the sunshine-blocked area became wider after the sunrise and before the sunset. The area of sunshine block after 1 hour at sunrise increased by 1.60%, 1.50%, 1.58% and 1.36% in the vernal equinox, summer solstice, autumnal equinox and winter solstice, respectively. The building complex in the east (south) of the PKNU campus made shadow in more than 1,000 m (750 m) toward the west (east) just before the sunrise (sunset). Especially, the sunshine duration in PKNU campus decreased by 46.61%, 22.75%, 58.56%, and 11.31% in the vernal equinox, summer solstice, autumnal equinox and winter solstice, respectively. The analysis of the sunshine duration for a dormitory building showed that the construction of the building complex in the south of the PKNU campus reduced the sunshine area of the western (southern) wall of the dormitory by 30.91% (49.45%) for a winter week.

Flight Activity and Injury Characteristics of Beet Armyworm, Spodoptera exigua(Hubner), (Lepidoptera: Noctuidae) in Southern Region of Korea (남부지방에서 파밤나방의 비산활동 및 가해특성)

  • 박종대;고현관;이재휴;이운직;김규진
    • Korean journal of applied entomology
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    • v.30 no.2
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    • pp.124-129
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    • 1991
  • This study investigated seasonal occurrence and daily flight activity using synthetic sex pherom mone and injury characteristics of 야et armyworm, Spodoptera exigua in Chonnam area of K Korea in 1990. Male adults were attracted to phermone trap from mid-June to late November w with the peaks at mid-late August, mid-late September and early-mid November in vinyl i house and also were attracted from mid October to late November in field. Primary peak of occurrence in vinyl house was 20 days sooner than field. It seems to have 6 generations a year in C Chonnam region based on the estimation of larval biomass. Daily male flight was active from m midnight to before sunrise with the peak at 4-6 A.M .. In injury characteristics at various host plants, damage was great in early growing stage at below 10 cm of plant height in Allium fistulsum. Chrysanthemum morifolium was damaged at mostly upper part of leaves reaching to m the extent up to 70%. In case of Gypsophila paniculata, plants injured at early growing stage do n not grow and flower normally.

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Effects of Timings and Light Intensities of Supplemental Red Light on the Growth Characteristics of Cucumber and Tomato Plug Seedlings (적색광 처리시기 및 광도가 오이 및 토마토 플러그묘의 생장에 미치는 영향)

  • Zhang, Cheng-Hao;Chun, Ik-Jo;Park, Yong-Chul;Kim, Il-Seop
    • Journal of Bio-Environment Control
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    • v.12 no.4
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    • pp.173-179
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    • 2003
  • This study was established to control the overgrowth of cucumber and tomato plug seedlings by controlling of irradiation timings light intensities of red (R) light. Compared with the control, end-of-day (EOD) timing of R irradiation significantly reduced the seeding heights by 21.3% and 14.2% in cucumber and tomato, respectively. In addition, both plant seedlings treated with R light at EOD timing had the thickest stem diameter. Tomato seedlings treated with R light at EOD showed th highest chlorophyll content and the smallest leaf size. Dry weights of above ground plant tissue in both plant seedlings were significantly reduced by EOD R light treatment. And both plant seedlings treated with EOD treatment had the lowest T/R ratio, and the highest compactness rates. The increased intensities of R light resulted in the shorter plant heights in cucumber and tomato plant seedlings. It also reduced the length of hypocotyls and internodes and the size of leaves in the both seedlings. Elevated R light intensities tended to increase the stem diameter and chlorophyll contents. Dry weights of above ground plant tissue and roots in both plant seedlings were reduced by the elevated R irradiation. Cucumber seedlings treated with 2 and 8 $mol{\cdot}m^{-2}{\cdot}s^{-1}$ and tomato seedlings treated with 8 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ had significantly lower T/R ratio the other treatments tested.

Characteristics of Surface Inversion Layer Observed in Winter at Ulsan Metropolitan City (울산광역시 동계 접지역전층의 특성)

  • 박종길;이희정;김재석;김종명
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.101-107
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    • 2003
  • 해가 지면서 지표면이 냉각되고 지표면의 냉각은 지표부근의 대기를 냉각시켜 상부의 대기보다 차가워지면서 대기의 상태가 안정 상태가 되는데 이 때를 접지 역전층이라고도 하고 야간 경계층이라고도 한다. 야간 경계층은 다음 날 해가 뜨기 전까지 계속 지속되는데 그 고도는 지상 수백m까지 확장될 수도 있다. 이러한 현상은 배출된 대기 오염 물질이 형성된 역전층에 의해 확산이나 수송이 방해를 받게된다. 역전층 상태에서의 오염물질의 배출은 직접적으로 영향을 미치지 않으나, 일출 이후 일사에 의한 지표의 가열로 역전층이 파괴되면서 역전층위의 고농도의 오염물질이 지상으로 유입되어 지표부근에 고농도의 오염을 유발할 수 있다. (중략)

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A Study on the Design of Automatic Flicker System for Unmanned Lighthouse Control (무인 등대 제어를 위한 자동 점멸 시스템의 설계에 관한 연구)

  • Park, Dong-Woo;Kim, Hyo-Min;Lee, Tae-Oh
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.1
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    • pp.387-390
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    • 2005
  • 전 세계는 국제 시장의 개방화로 인하여 해상을 통한 수${\cdot}$출입 컨테이너 화물량이 크게 증가하고 있다. 이에 선박이 항해 중 가장 중요한 것은 자선의 위치를 정확히 파악하여 안전하고 경제적인 항로를 이용하여 효과적으로 운항을 도모하는 것이다. 따라서 본 논문에서는 선박의 안전한 운항을 도모하기 위해서 항만, 연${\cdot}$근해에 설치되어 있는 무인등대의 효율적인 관리를 위한 자동 점멸 시스템의 설계에 관한 연구이다. 본 시스템은 GPS를 통한 일출과 일몰 시간의 동기화와 다른 해양 환경 조건을 고려하여 광센서와 습도센서를 추가 이용하여 무인 등대의 자동 점멸 시스템을 설계 및 구축한다.

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