• Title/Summary/Keyword: 일몰

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MF DGNSS 인프라를 이용한 항법 신호의 야간 특성 분석

  • 손표웅;한영훈;서기열;황태현
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2022.06a
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    • pp.412-414
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    • 2022
  • Global Navigation Satellite Systems (GNSSs)을 이용한 위치정보 서비스가 다양해짐에 따라, 전파 교란 및 기만에 대한 GNSSs의 취약성에 대한 우려도 점점 커지고 있다. 이에 미국, 러시아, 유럽 등 자체적으로 GNSS를 보유하고 운영하고 있는 국가조차도 GNSS의 취약성을 보완할 수 있는 부가적인 항법시스템을 개발하고 있다. 그 중 현재 운영 중인 Medium Frequency (MF) 주파수 대역의 신호를 이용하여 Differential GNSS (DGNSS) 정보를 전달하는 인프라를 활용하여 항법 신호를 송출하는 Ranging Mode (R-Mode) 시스템이 유럽과 한국을 중심으로 개발 중에 있다. 하지만 MF 주파수 대역의 신호는 일몰 이후에 전리층 일부가 소멸되면서 상위 전리층에서 신호가 반사되어 지표면에서 강한 세기로 수신되는 특성을 갖고 있다. 이런 특성은 지표를 통해 전파하는 원 신호를 수신하는 과정에 큰 오차요소로 작용할 수 있다. 본 논문에서는 현재 송출되고 있는 R-Mode 신호의 야간 특성을 분석하고자 한다. 현재 충주, 어청도 DGNSS 기준국에서 송출하고 있는 R-Mode 신호를 다양한 안테나 종류로 수신해보고, 항법 시스템의 정밀도 성능에 악영향을 줄 수 있는 특성에 대한 보완방법을 모색하였다.

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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.

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.

Study on the Centipede Bite Cases Who Visited a Medical Center (일개 의료원을 방문한 지네 교상 환례에 대한 조사)

  • Lee, Dong-Uk
    • Journal of agricultural medicine and community health
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    • v.27 no.1
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    • pp.79-86
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    • 2002
  • Thirty six patients, female 21(58.4%), male 15(58.4%), with centipede bite visited emergency room of Gimcheon Medical Center, from September 1998 to August 1999. The number of patients accompanying the seasons were increased once in June and were high in August and September; peaked in September, which conforms to the habitude that centipede likes the warmer climate. Frequency accompanying the time was high after sunset(from 6 p.m. to 6 a.m. next morning) than before sunset, which conforms to the habitude that centipede is nocturnal. Distribution of the bite sites was finger(30%), neck(28%), foot(25%) and hand(14%) as same as the previous researches showed. In case of finger and hand, patients got bitten while they were wearing gloves or doing works; foot, wearing shoes. They got bitten the neck while sleeping. Among the localized symptoms were localized pain: 36 patients(100%), swelling: 36 patients(100%), erythema: 26 patients(72.2%), paresthesia: 5 patients (13.9%). Systemic symptoms were dizziness 2 patients(5.6%) and nausea 1 patient(2.8%). Mostly the localized pain was improved within 48 hours, swelling in 48 hours and within 72 hours in case of paresthesia. Systemic symptoms such as dizziness and nausea were improved within 24 hours. Treatment and prognosis of scolopendra have similarity in many countries. We suggest that Korean standard treatment manual is needed so that the localized symptom, systemic symptom and external wound can be cured soon.

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Characterization of Photosynthetic Rates by Tomato Leaf Position (토마토 엽위별 광합성 특성 분석)

  • Kim, Sung Eun;Lee, Moon Young;Kim, Young Shik
    • Horticultural Science & Technology
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    • v.31 no.2
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    • pp.146-152
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    • 2013
  • The photosynthetic rates according to leaf positions in tomato plants were investigated in relation to leaf age and flowering rate. In the experiment investigating the diurnal change of photosynthetic rates, three leaves below the 4th cluster was checked every hour from 2 hours before sunrise and 3 hours after sunset. It was checked twice with the replication of 3 plants. The photosynthetic rate increased sharply for 1 hour right after sunrise and remained steady until 2 hours before sunset. This trend can be applied to determine the irrigation schedule. In the experiment investigating the photosynthetic rates according to leaf positions, it three leaves below each clusters from 1st to 4th cluster were checked. Flowering rate was also investigated. The photosynthetic rates showed a decreasing tendency steadily after flowers bloomed fully, regardless of the leaf position. It seems to be because the leaves below the cluster with fully-bloom flowers lost their activities. This result suggests the flowering rate or the position of flower has deep relation with the photosynthetic rates of the concerned leaves. From the results the leaves under flowering cluster may be the good part to investigate the photosynthetic rate to evaluate the crop's activity, even the photosynthetic rates are different according to the position of clusters.

Impact Assessment of Vegetation Carbon Absorption and Economic Valuation Under Long-term Non-executed Urban Park Development (장기미집행공원 개발에 따른 도시 식생 탄소 흡수량에 미치는 영향 및 경제적 가치 평가)

  • Sung, Woong-Gi;Choi, Jae-Yeon;Yu, Jae-Jin;Kim, Dong-Woo;Son, Seung-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.10
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    • pp.361-371
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    • 2020
  • Since the implementation of the sunset law in 2020, concerns have been raised over the reckless development of long-term non-executed urban parks. In this study, the FSDAF method and CASA-NPP model were used to evaluate the annual average NPP of long-term non-executed urban parks in Seoul. Based on this, the carbon loss and economic value were assessed under five development scenarios. The total NPP value of long-term non-executed urban parks, except for the greenbelt area in Seoul, was 4,892.18 t C. In the first scenario, the NPP and cost were 4,892.18 t C of vegetation carbon and 1.18 billion won, 2,548.55 t C of vegetation carbon and 615 million won in the second scenario, 238.94 t C of vegetation carbon and 58 million won in the third scenario, 848.38 t C of vegetation carbon and 205 million won in the fourth scenario, and 1,596.00 t C of vegetation carbon and 385 million won in the fifth scenario. These results are meaningful for evaluating vegetation carbon and economic value loss according to five different development scenarios. The results of this study are expected to be useful for the preparation of measures to minimize the impact of the development of long-term non-executed urban parks.

A Study on the Comparison Between China's Anti-Dumping System and WTO Agreement (중국 반덤핑 법규와 WTO 규범과의 적합성 비교 연구)

  • Shin, Sung-Shik;Choi, Hae-Bum
    • International Commerce and Information Review
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    • v.13 no.4
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    • pp.323-349
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    • 2011
  • As China is one of WTO member nations, It has an obligation to have to certainly keep a standard regarding anti-dumping systems deciding in WTO agreements. Nonetheless the Chinese anti-dumping laws is causing legal uncertainty because of insufficient details regulations about the account of dumping margins, the termination of an investigation in case of negligible imports, and sunset review And a part of regulations are disagreed with WTO anti-dumping agreement about price undertakings. Therefore, South Korea should indicate them and urge the Chinese government to revise them so that its anti-dumping Law is agreed with WTO agreement. Aside from this, if the anti-dumping investigation is initiated, South Korea government must observe how the Chinese authorities operates its anti-dumping law that do not agree with WTO agreement, and should prepare the countermeasure accordingly. The analysis of this study is concentrated on the compatibility of the WTO anti-dumping agreement with China's interpretation of the antidumping policy and public law. Also, Including our export company, government agencies, academic circles being related, and international trade advisory agencies must expand opportunity of information sharing.

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Current Research Trends in Wood Preservative for Enhanced Durability : A Literature Review on Copper Based Preservatives (옥외 내구성 향상을 위한 목재보존제의 최근 연구 동향 - 구리 기반 약제를 중심으로 -)

  • Kim, Yeong-Suk
    • Journal of the Korean Wood Science and Technology
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    • v.40 no.3
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    • pp.212-227
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    • 2012
  • Current research trends in wood preservatives for enhancing durability was reviewed. Due to leaching of recent Copper-Based Preservatives commonly used as chemicals for pressure treatment; they have been a growing concern, especially in improving the fixation of the copper as alkyl ammonium quat. and azol in wood and preventing the leaching of active ingredients. With the appearance of emulsion type chemicals using micronized and nano-sized wood preservatives, researchs on characteristics of Copper-Based Preservatives regarding penetration and fixation in wood are debatable. Moreover, unlike the case of CCA, the recent alkyl ammonium quat. and azol bear a serious threat in the decrease of antimicrobial effectiveness against wood destroying fungi with copper tolerance. Therefore, development and research of co-biocide is needed.

Variations of Turbulent Fluxes in the Atmospheric Surface Layer According to the Presence of Cloud (구름 유무에 따른 대기표층 난류속의 변화)

  • de Oliveira Junior, Jose Francisco;Kwon, Byung-Hyuk
    • Journal of the Korean earth science society
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    • v.25 no.2
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    • pp.87-93
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    • 2004
  • To study the effect of cloud on the variabilities of turbulent fluxes over the flat terrain, we used the gradient method to analyze the dynamic and thermodynamic data from the meteorological 9-m mast (0.75, 3 and 9 m) in Villafria airport in Spain. The decrease of the surface wind speed is governed by cooling at the surface following the evening transition. The sensible heat flux and the momentum flux are increased with the dynamic factor rather than the thermodynamic factor, and the sensible heat flux was not affected by the thermal condition. The global radiation did not play an important role in the variation of the sensible heat flux in the cloudy day, but the atmospheric surface layer was characterized rather by the wind intensity.

Reappearance of the Phase Difference of Omega at Busan (부산지방에서의 오메가위상차의 재현성)

  • Ahn, Jang-Young
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.18 no.2
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    • pp.97-100
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    • 1982
  • The phase differences of the omega were observed continuously for the A-C pair and the A-E pair from Sept. 1, 1980 to Feb. 28, 1981 and from Sept. 20, 1981 to Feb. 82, 1982 at Fisheries University of Busan350$^{\circ}$ 07'.9N, 129$^{\circ}$ 06'.3E)In this paper we deal with the reappearance of these phase differences by annual, month, day As a results, annual eappearance are in good condition both pairs and daily reappearance in day and night are better than an hour around the sunset, and very bad reappearance is found by month.

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