• Title/Summary/Keyword: Cold region

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Directional solidification by the skull melting in the $YO_{1.5}-BaO-CuO$ system (Skull melting 방법에 의한 $YO_{1.5}-BaO-CuO$계의 방향적 결정성장)

  • Chung, Yong S.;Hill, D. Norman
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.4 no.2
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    • pp.148-156
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    • 1994
  • Three composition in the system of $YO_{1.5}-BaO-CuO$ were grown using a cold crucible (skull) melting technique with a 50 kW R.F. induction generator operating at 4 MHz as the power source. The starting materials were prepared by conventional ceramic powder processing methods, loaded into the skull, and melted at about $1200^{\circ}C$. For this study, compositions near the $YBa_2Cu_3O_X$ region were selected. The growth rates used ranged from 4 cm/hr to 0.25 cm/hr. The relation between the microstructures and the starting composition of each ingot was determined using metallograph, X-ray diffraction, and energy dispersive X-ray analysis. Both $YBa_2Cu_3O_X$ and $Y_2BaCuO_5$ needle-shaped crystals, aligned with the growth direction, were formed in the $CuO-BaCuO_2$ eutectic matrix of the $YBa_2Cu_7O_x and YBa_5Cu_{11}O_x$ ingot.

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Warm Season Hydro-Meteorological Variability in South Korea Due to SSTA Pattern Changes in the Tropical Pacific Ocean Region (열대 태평양 SSTA 패턴 변화에 따른 우리나라 여름철 수문 변동 분석)

  • Yoon, Sun-kwon;Kim, Jong-Suk;Lee, Tae-Sam;Moon, Young-IL
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.1
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    • pp.49-63
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    • 2016
  • In this study, we analyzed the effects of regional hydrologic variability during warm season (June-September) in South Korea due to ENSO (El $Ni{\tilde{n}}o$-Southern Oscillation) pattern changes over the Tropical Pacific Ocean (TPO). We performed composite analysis (CA) and statistical significance test by Student's t-test using observed hydrologic data (such as, precipitation and streamflow) in the 113 sub-watershed areas over the 5-Major River basin, in South Korea. As a result of this study, during the warm-pool (WP) El $Ni{\tilde{n}}o$ year shows a significant increasing tendency than normal years. Particularly, during the cold-tongue (CT) El $Ni{\tilde{n}}o$ decaying years clearly decreasing tendency compared to the normal years was appeared. In addition, the La $Ni{\tilde{n}}a$ years tended to show a slightly increasing tendency and maintain the average year state. In addition, from the result of scatter plot of the percentage anomaly of hydrologic variables during warm season, it is possible to identify the linear increasing tendency. Also the center of the scatter plot shows during the WP El $Ni{\tilde{n}}o$ year (+17.93%, +26.99%), the CT El $Ni{\tilde{n}}a$ year (-8.20%, -15.73%), and the La $Ni{\tilde{n}}a$ year (+8.89%, +15.85%), respectively. This result shows a methodology of the tele-connection based long-range water resources prediction for reducing climate forecasting uncertainty, when occurs the abnormal SSTA (such as, El $Ni{\tilde{n}}o$ and La $Ni{\tilde{n}}a$) phenomenon in the TPO region. Furthermore, it can be a useful data for water managers and end-users to support long-range water-related policy making.

A STUDY ON THE IONOSPHERE AND THERMOSPHERE INTERACTION BASED ON NCAR-TIEGCM: DEPENDENCE OF THE INTERPLANETARY MAGNETIC FIELD (IMF) ON THE MOMENTUM FORCING IN THE HIGH-LATITUDE LOWER THERMOSPHERE (NCAR-TIEGCM을 이용한 이온권과 열권의 상호작용 연구: 행성간 자기장(IMF)에 따른 고위도 하부 열권의 운동량 강제에 대한 연구)

  • Kwak, Young-Sil;Richmond, Arthur D.;Ahn, Byung-Ho;Won, Young-In
    • Journal of Astronomy and Space Sciences
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    • v.22 no.2
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    • pp.147-174
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    • 2005
  • To understand the physical processes that control the high-latitude lower thermospheric dynamics, we quantify the forces that are mainly responsible for maintaining the high-latitude lower thermospheric wind system with the aid of the National Center for Atmospheric Research Thermosphere-Ionosphere Electrodynamics General Circulation Model (NCAR-TIEGCM). Momentum forcing is statistically analyzed in magnetic coordinates, and its behavior with respect to the magnitude and orientation of the interplanetary magnetic field (IMF) is further examined. By subtracting the values with zero IMF from those with non-zero IMF, we obtained the difference winds and forces in the high-latitude 1ower thermosphere(<180 km). They show a simple structure over the polar cap and auroral regions for positive($B_y$ > 0.8|$\overline{B}_z$ |) or negative($B_y$ < -0.8|$\overline{B}_z$|) IMF-$\overline{B}_y$ conditions, with maximum values appearing around -80$^{\circ}$ magnetic latitude. Difference winds and difference forces for negative and positive $\overline{B}_y$ have an opposite sign and similar strength each other. For positive($B_z$ > 0.3125|$\overline{B}_y$|) or negative($B_z$ < -0.3125|$\overline{B}_y$|) IMF-$\overline{B}_z$ conditions the difference winds and difference forces are noted to subauroral latitudes. Difference winds and difference forces for negative $\overline{B}_z$ have an opposite sign to positive $\overline{B}_z$ condition. Those for negative $\overline{B}_z$ are stronger than those for positive indicating that negative $\overline{B}_z$ has a stronger effect on the winds and momentum forces than does positive $\overline{B}_z$ At higher altitudes(>125 km) the primary forces that determine the variations of tile neutral winds are the pressure gradient, Coriolis and rotational Pedersen ion drag forces; however, at various locations and times significant contributions can be made by the horizontal advection force. On the other hand, at lower altitudes(108-125 km) the pressure gradient, Coriolis and non-rotational Hall ion drag forces determine the variations of the neutral winds. At lower altitudes(<108 km) it tends to generate a geostrophic motion with the balance between the pressure gradient and Coriolis forces. The northward component of IMF By-dependent average momentum forces act more significantly on the neutral motion except for the ion drag. At lower altitudes(108-425 km) for negative IMF-$\overline{B}_y$ condition the ion drag force tends to generate a warm clockwise circulation with downward vertical motion associated with the adiabatic compress heating in the polar cap region. For positive IMF-$\overline{B}_y$ condition it tends to generate a cold anticlockwise circulation with upward vertical motion associated with the adiabatic expansion cooling in the polar cap region. For negative IMF-$\overline{B}_z$ the ion drag force tends to generate a cold anticlockwise circulation with upward vertical motion in the dawn sector. For positive IMF-$\overline{B}_z$ it tends to generate a warm clockwise circulation with downward vertical motion in the dawn sector.

Effect of Blue Color-deficient Sunlight on the Productivity and Cold Tolerance of Crop Plants (청색파장(靑色波長)영역이 결여된 태양광이 작물(作物)의 생산성(生産性) 및 내냉성(耐冷性)의 향상에 미치는 효과 Ⅰ. 광합성(光合成) 및 호흡(呼吸)의 전자전달계 활성(活性)의 변화)

  • Jung, Jin;Kim, Jong-Bum;Min, Bong-Ki
    • Korean Journal of Environmental Agriculture
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    • v.5 no.2
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    • pp.141-148
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    • 1986
  • The blue-light effect on the grown as well as on the physiological activity of some major horticultural plants in Korea has been investigated. The light quality used for the work was obtained from sunlight filtered by an orangecolored polyethylene film which removed about 70% of visible light in the spectral region of $350㎚{\sim}500㎚$. The film was developed in this laboratory especially for the work and named BCR film meaning blue color-removing film. The light environment in the plastic house which was built with BCR film provided plants with the blue color-deficient sunlight. Thus, the photobiological effect of blue light could be examined conversely by comparing with the effect of white sunlight in a conventional plastic house built with colorless polyethylene film. In a sense of applicability to horticulture, two remarkable effects of the blue color-deficient sunlight on plant physiology were observed: First, it enhanced to a great extent the growth activity of plants-pepper, cucumber, zucchini, tomato, and leaf lettuce at the vegetative stage as well as at the reproductive stage, as demonstrated by their yield which were in average $40{\sim}50%$ increased compared with the control (under white sunlight). Second, it improved significantly the cold tolerance of plants, as exhibited with their resistance to chilling during treatment in a cold chamber maintained at a temperature which caused chilling injury to the plants of control. The visualized effects were reflected on the physiological activity of cells on organelle level. Chloroplast isolated from the plant leaves grown under BCR film showed considerably stronger photosynthetic activity, as judged by the increased electron transport rate of illuminated chloroplast, than that from leaves grown under white PE film. Mitochondria from leaves grown under BCR film maintained normal respiration activity until temperature decreased to a few degree($^{\circ}C$) lower than the temperature which caused respiratory inhibition to mitochondria obtained from leaves of the control.

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A Study on Sea Water and Ocean Current in the Sea Adjacent to Korea Peninsula -III. Chemical Characteristics of Water Masses in the Polar Front Area of the Central Korean East Sea- (한반도 근해의 해류와 해수특성 -III. 한국 동해 중부 극전선역에 출현하는 수괴의 화학적 특성-)

  • YANG Han-Soeb;KIM Seong-Soo;KANG Chang-Geun;CHO Kyu-Dae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.24 no.3
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    • pp.185-192
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    • 1991
  • The vertical distribution and chemical characteristics of water masses were measured along two south-north transects in the polar front region of the central Korean East Sea. In February, a thermocline was present at depth between 50m and loom at the southern sites of a landward A-transect, and its depth was gradually deepened northward. At an outside B-transect, a thermocline was observed at significantly deep depth of 300m to 400m at two northern stations(Stn. 10 and 11), though the depth of the southward stations was nearly identical to that at the northward stations on a A-transect. In September, there were vertically more various water masses, i.e. the Tsushima Warm surface water(TWSW) or more than $20^{\circ}C$, the Tsushima Middle water(TMW) with a range of $12{\~}17^{\circ}C$, the North Korea Cold Water(NKCW) with $1{\~}7^{\circ}C$ temperature, the Japan Sea Proper Water(JSPW) of less than $1^{\circ}C$, and the mixed water. The North Korea Cold Water could be distinguishable from the other waters, especially from the mixed water of the Tsushima Middle Water and the Japan Sea Proper Water by the pattern of $T-O_2$ diagram. For instance, the North Korea Cold Water had higher oxygen by $1{\~}2ml/l$ than those in the mixed water, although both the two water masses ranged $1{\~}7^{\circ}C$ in water temperature. AOU value was the highest in the JSPW and the lowest in the TWSW. Also, AOU indicated a nearly linear and negative correlation with water temperature. However, AOU data for two masses, the NKCW and the TMW, in September departed remarkably from a regression line. Moreover, the ratio of $$\Delta P/\Delta AOU)$ in September was about $0.45{\mu}g-at/ml$ and higher than the value observed in the open sea. This high value could be elucidated by two factors; intrusion of the NKCW with high oxygen and molecular diffusion of dissolved oxygen from the surface into the lower layer. AOU would be a useful tracer for water masses in the polar front area of the Korean East Sea.

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A New High-yielding Winter Oat Cultivar for Whole Crop Forage, 'Dahan' (내한 다수성 추파 조사료용 총체 귀리 신품종 '다한')

  • Han, Ouk-Kyu;Park, Tae-Il;Park, Hyung-Ho;Song, Tae-Hwa;Kim, Kee-Jong;Park, Nam-Geon;Ju, Jung-Il;Jang, Young-Jik;Hwang, Jong-Jin;Kwon, Young-Up
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.34 no.1
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    • pp.26-32
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    • 2014
  • 'Dahan' (Avena sativa L.), a winter oat cultivar for forage use, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute Crop Science (NICS), Rural Development Administration (RDA) in 2011. It was derived from an original cross between $F_1$[Sprinter/73625] and 'Gwiri26'. Subsequent generations followed by the cross were handled in bulk and pedigree selection programs at Suwon. A line, 'SO99027-GB-B-113-4-4-3', was selected for cold tolerance and good agronomic characteristics and as a line name of 'Gwiri75'. The line 'Gwiri75' was subsequently evaluated for cold tolerance and forage yield during 3 years in four region such as Yesan, Iksan, Kimjae, and Jeju, from 2009 to 2011 and finally named as 'Dahan'. Though similar in heading date to the check cultivar Samhan, 'Dahan' had tall plant length and lodging resistance. It's average forage dry matter yield harvested at milk-ripe stage was 15.6 ton $ha^{-1}$, compared with 14.1 ton $ha^{-1}$ of check cultivar. Cultivar 'Dahan' was lower to the check cultivar 'Samhan' in protein content (8.4% and 9.9%, respectively), while it was superior to the check cultivar in total digestible nutrients (TDN) (60.8% and 59.3%, respectively), and in TDN yield $ha^{-1}$ (9.5 ton and 8.4 ton, respectively). Fall sowing of 'Dahan' is recommended only in the areas where daily minimum mean temperatures are averaged higher than $-7^{\circ}C$ in January, and excluded in mountain area where frost damage is presumable.

A Bibliographical Research of the Correlation Among Sasang Constitutional Disease(사상체질병증) and the Pulse Diagnosis(맥진) (사상체질병증(四象體質病症)과 맥진(脈診)의 상관성(相關性)에 대(對)한 문헌적(文獻的) 고찰(考察))

  • Kim, Dong-Jun;Kim, Jung-Ryul;Kim, Dal-Rae
    • Journal of Pharmacopuncture
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    • v.6 no.3
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    • pp.23-37
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    • 2003
  • The purpose of this research was to investigate the correlation Among Sasang Constitutional Disease and Examination of the pulse. I have gone over literatures of mainly ${\ulcorner}$Dongyi Soose Bowon${\lrcorner}$ and the others Oriental Medical book was studied about the Pulse Diagnosis. And then I came to get some conclusion as follows. 1. Soeumin(소음인) the initial-stage symptoms of wulkwang disease(울광증) ; when the Superficial Pulse and the Superficial+ Moderate Pulse is made a diagnosis, Ceongunggyegitang(천궁계지탕) and Gunggyuhyangsosan(궁귀향소산) can be used. 2. Soeumin(소음인) the initial-stage blood disease symptoms of wulkwang disease(울광증) ; when the Minute+deep Pulse is made a diagnosis, Palmulgnnjatang(팔물군자탕) and Guakhyanggeonggisan(곽향정기산) can be used. 3. Soeumin(소음인) the initial-stage symptoms of mangyang disease(망양증) ; when the Yang region Superficial Pulse and the Yin region Weak Pulse is made a diagnosis, Hwanggigyegitang(황기계지탕), Bojungikgitang(보증익기탕) and Sengyangikgitang(승양익기탕) can be used. 4. Soeumin(소음인) the symptoms of taeum disease(태음증) ; when the Minute Pulse and Deep+Thin Pulse is made a diagnosis, Sasang Prescription can be used. 5. Soeumin(소음인) the symptoms of soeum disease(소음증) ; when the Minute+Thin Pulse, Deep Pulse and Thin+Deep+Rapid Pulse is made a diagnosis, Sasang Prescription can be used. 6. Soyangin(소양인) Wind of soyang disease(소양상풍증) ; when the Superficial+Tight Pulse is made a diagnosis, Hungbangpaedogsan(형방패독산) can be used. And when the Deep+Full with strong power Pulse is made a diagnosis, Hyungbangdojeoksan(형방도적산) can be used. 7. Soyangin(소양인) the symptoms of mangyeum disease(망음증) ; when the Superficial+Large+Rapid Pulse and Flood+Large Pulse is made a diagnosis, Hungbangsabaeksan(형방사백산) can be used. And when the Wiry+Thin Pulse is made a diagnosis, Hungbanggiwhangtang(형방지황탕) can be used. 8. Soyangin(소양인) the chest-phrenic fever syndrome(흉격열증) ; when the Superficial Pulse, Flood+Full+Rapid Pulse and Flood+Large Pulse is made a diagnosis, Sasang Prescription can be used. 9. Soyangin(소양인) the after fever syndrome(음허오열증) ; when the Empty+Soft+Rapid Pulse is made a diagnosis, Sasang Prescription can be used. 10. Taeumin(태음인) the upper neck exterior disease caused by Cold(배추표병) ; when the Superficial and Superficial+Tight Pulse is made a diagnosis, Mawhangbalpoytang(마황발표탕) can be used, And when the Superficial and Superficial+Tight with strong power on left hand Pulse is made a diagnosis, Ungdamsan(웅담산) and Handayulsotang(한다열소탕) can be used. 11. Taeumin(태음인) the Coldness syndrome in esophagus(위완한증) ; when the Superficial+Tight Pulse with weak power on left hand Pulse is made a diagnosis, Taeumjowetang(태음조위탕) can be used. 12. Taeumin(태음인) the Dryness-Heat syndrome(조열증) ; when the Flood+Large Pulse, Long Pulse and Long+Large Pulse is made a diagnosis, Galgeunhaegitang(갈근해기탕) can be used. And when the Tight+Full+Rapid Pulse with deep region is made a diagnosis, Yuldahansotang(열다한소탕) can be used. And when the Superficial+Slippery Pulse is made a diagnosis, Chungsimyunjatang(청심연자탕) can be used. 13. Taeumin(태음인) the symptoms of Yin-blood Exhaustion(음혈모갈증) ; when the Superficial with weak power Pulse is made a diagnosis, Nokyongdaebotang(녹용대보탕) can be used. And when the Deep with weak power Pulse is made a diagnosis, Gongjinheukwondan(공진흑원단) can be used. 14. Taeyangin(태양인) a slight Lumbar vertebrae disease(외감경증) ; when the Superficial+Hollow Pulse is made a diagnosis, Gunshitang(건시탕) can be used. 15. Taeyangin(태양인) the Generalized and Fatigue syndrome(해역증) ; when the Moderate+Choppy Pulse with left hand chi region(척맥) is made a diagnosis, Ogapijangchuktang(오가피장척탕) can be used. 16. Taeyangin(태양인) a slight Small Intestine disease(내촉경증)

On the Characteristic and Representation of Kyodong Island Soundscape (교동도 사운드스케이프의 특성과 재현)

  • Kim, Ji-na;Zoh, Kyung-Jin;Kwon, Byung-Jun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.47 no.1
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    • pp.57-75
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    • 2019
  • Soundscapes have the potential to help people experience the historical background and cultural traditions by the scenery of a local area and to be used as a cultural and tourism resource. This concept was first explained in detail by M. Schafer and has been developed as a new way of experiencing landscapes using various senses. This research studied the soundscape of Kyodong Island, the so-called "Island of Peace" and designed new cultural acoustic content for education and tourism. Kyodong Island is located right below the Northern Limit Line and the whole island is in the Civilian Controlled Area. The political and economic status of the island has been changed dynamically by the Korean War and the division of the country. These days, the island needs to realize the vision of the "Island of Peace" in a more creative way using local resources, including its "cold war landscape" and the natural scenery of the region. This research applied the concept of a soundscape to document the island, and to reproduce it in an artistic way. A workshop was conducted to learn concepts and techniques of soundscapes with a sound artist. Listening, recording, conducting interviews, and literature research was used to study the soundscape of the island. After that, this research reconstructed the soundscape of the island through a soundscape composition. The main theme of the composition story was the "Hope and Wish for the Harmony and Peace" to show the vision of the "Island of Peace". The initial sub-theme for the introduction part was "First Encounter with Kyodong Island" arranging the representative soundscape, which could be the first impression of the region. The second sub-theme was "War and Tension" using several soundscapes as a metaphor for the tragedy of the Korean War. The third sub-theme was "Everyday Life of Kyodong Island" which described the energy of the present day, after the wounds of the war have healed. The final sub-theme was "Harmony and Peace" using traditional music and keynote sounds of the region as a reminder of the peaceful past, before the war. The recording files were documented as two types of sound maps. One was a two-dimensional map to show the soundscapes from one point of view, and the other used the online application called "Sound Around You". The final artwork was displayed at an exhibition and uploaded on YouTube to be shared publicly. Through this project, we discovered the potential of soundscapes as a medium to preserve the history and local identity, as well as presenting a new vision. The artwork will be exhibited at historically and culturally meaningful places on the Island to utilize the underused places as local tourist attractions and educational resources.

The Surface Distribution of Dissolved Gases in the Southwestern East Sea: Comparison of the Primary Production and CO2 Absorption in Summer between Coastal Areas and the Ulleung Basin (동해 남서부해역의 표층 용존 기체 분포: 여름철 연안과 울릉분지의 일차생산력과 CO2 흡수 비교)

  • LEE, INHEE;HAHM, DOSHIK
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.26 no.4
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    • pp.327-342
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    • 2021
  • The global coastal region is considered as a sink for atmospheric CO2. Since most of the studies in the East Sea focused on the Ulleung Basin, the importance of coastal region for carbon cycle has been overlooked. In this study, we compared the biological pump and CO2 absorption between the Ulleung Basin and coastal region by surface measurements of biological O2 supersaturation (𝚫O2/Ar) and partial pressure of CO2 (fCO2). Cold and less saline waters in the coastal regions were in contrast with a warm and saline water in the Ulleung Basin. The coastal waters near Samcheok and Pohang showed higher fluorescence, 𝚫O2/Ar, and lower fCO2 than those in the Ulleung Basin, indicating higher primary production and CO2 absorption in the areas. The average net community production estimated by 𝚫O2/Ar were 19 ± 6 and 60 ± 9 mmol O2 m-2d-1 in the Samcheok and Pohang, respectively, 2-7 times higher than that of 8 ± 4 mmol O2 m-2d-1 in the Ulleung Basin. Similarly, the average CO2 flux between the seawater and atmosphere were -17.1 ± 8.9 and -25.8 ± 13.2 mmol C m-2d-1 in the Samcheok and Pohang, respectively, 4-5 times higher than that of -4.7 ± 2.5 mmol C m-2d-1 in the Ulleung Basin. In the Samcheok and Pohang, degrees of N2 saturation were lower by 3% than that the ambient waters, suggesting the possibility of nitrogen fixation by primary producers.

Studies on the Breeding of Cold Hardiness and Technique of Overwintering Cultivation in Citrus (감귤(柑橘)의 내한성(耐寒性) 품종육성(品種育成) 및 내한(耐寒) 재배기술(栽培技術)에 관(關)한 연구(硏究))

  • Kim, Chi-moon;Song, Ho-kyung;Kim, Chung-suk
    • Korean Journal of Agricultural Science
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    • v.4 no.2
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    • pp.126-140
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    • 1977
  • Present studies were carried out for breeding cold resistant clones of Citrus, improving overwintering techniques of Citrus in Jeju island as well as other southern region, Result obtained were as follows 1. In the vinyl house covered with two sheets of straw mat, 12 indivuals were found as non-injury and 15 were slightly injured by leaf freeging test at $-9^{\circ}C$ for 2 hours treatment. 2. In the condition of vinyl house covered with straw mat and viny film mulching and heat-in by sun-light, the inside temperature of vinyl house were not lowered below $-3^{\circ}C$ and the ground temperatura in vinyl house keeps above $0^{\circ}C$ during winter though outdoor temperature were lower by $-15^{\circ}C$(Daejeon area). 3. The vinyl tunnel inside the vinyl house and vinyl film mulching on ground position showed greater effectiveness for preventing heat loss from house but there were no significant difference between the color of vinyl film covered the tunnel. 4. In the vertical distribution of maximum temperature in vinyl house, the upper space was slightly higher than the lower position at high temperature condition, while minimum temperature was distributed as higher as the middle position, ground surface and upper position in order at low temperature condition 5. In the horizontal distribution of temperature in vinyl house, ground and surface-temperature of north side was lower than the other sides, and citrus planted within 30cm from north side wall died by cold injury and in the other side near wall appeared slight symptom of cold injury. 6. The insulating trench ($30{\times}30{\times}30cm$) packed with straw bundle installed under north wall might be effective to prevent heat loss of ground temperature. 7. In cloudy and snowy day, the temperature difference between indoor and outdoor were less, and the indoor temperature were maintained highly during night due to the effect of prevention of heat loss. 8. The highest temperature in a day was observed at about P.M. 3 both inside and outside of vinyl house and the lowest temperature was observed at about A.M. 6. The difference between the highest and lowest temperature of indoor in a sunny day was $19^{\circ}C$, compared with $9^{\circ}C$ on a cloudy or snowy day in late November. Especially, lowering of temperature in a snowy day was so less that the curve of temperature change was comparatively constant, 9. If the effective methods of citrus cultivation in vinyl house with improved clone such as hardiness. semi-dwarf and spur type are applied, it might be possible to cultivate the citrus tree safely in Jeju island as well as other southern rejion and to magnity the cultivation of citrus tree.

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