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Development of an Adaptive Capacity Indicator to Climate Change in the Agricultural Water Sector (농업용수의 기후변화 적응능력 지표 개발 - 가뭄에 대한 적응을 중심으로 -)

  • Yoo, Ga-Young;Kim, Jin-Teak;Kim, Jung-Eun
    • Journal of Environmental Policy
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    • v.7 no.4
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    • pp.35-55
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    • 2008
  • Assessing vulnerability to climate change is the first step to take when setting up appropriate adaptation strategies. Adaptive capacity to climate change is the important factor comprising vulnerability. An adaptive capacity index in agricultural water management system was developed considering agricultural water supply and demand for rice production in Jeolla-do, Korea. The agricultural water supply was assumed to be equal to the amount of water stored in the major agricultural reservoirs, while data on the agricultural water demand was obtained from the dynamic simulation results by Korea Agriculture Corporation(KAC). The spatial unit for analysis was conducted at the county(Si, Gun, Gu) level and temporal scale was based on every month from 1991-2003. Adaptive capacity for drought stress index(ACDS index) was calculated as the percentage of data points where the irrigated water supply was greater than the crop water demand. The ACDS index was compared with SWSCI(Standard Water Storage Capacity Index) and the relationship showed high degree of fit($R^2$=0.84) using the exponential function, indicating that the developed ACDS index is useful for evaluating the status of the balance between agricultural water supply and demand, especially for the small sized agricultural reservoirs. This study provided the methodological basis for developing climate change vulnerability index in agricultural water system which is projected to be more frequently exposed to drought condition in the future due to climate change. Further research should be extended to the study on the water demand of the crops other than rice and to the projection of the change in ACDS index in the future.

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Development of a TBM Advance Rate Model and Its Field Application Based on Full-Scale Shield TBM Tunneling Tests in 70 MPa of Artificial Rock Mass (70 MPa급 인공암반 내 실대형 쉴드TBM 굴진실험을 통한 굴진율 모델 및 활용방안 제안)

  • Kim, Jungjoo;Kim, Kyoungyul;Ryu, Heehwan;Hwan, Jung Ju;Hong, Sungyun;Jo, Seonah;Bae, Dusan
    • KEPCO Journal on Electric Power and Energy
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    • v.6 no.3
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    • pp.305-313
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    • 2020
  • The use of cable tunnels for electric power transmission as well as their construction in difficult conditions such as in subsea terrains and large overburden areas has increased. So, in order to efficiently operate the small diameter shield TBM (Tunnel Boring Machine), the estimation of advance rate and development of a design model is necessary. However, due to limited scope of survey and face mapping, it is very difficult to match the rock mass characteristics and TBM operational data in order to achieve their mutual relationships and to develop an advance rate model. Also, the working mechanism of previously utilized linear cutting machine is slightly different than the real excavation mechanism owing to the penetration of a number of disc cutters taking place at the same time in the rock mass in conjunction with rotation of the cutterhead. So, in order to suggest the advance rate and machine design models for small diameter TBMs, an EPB (Earth Pressure Balance) shield TBM having 3.54 m diameter cutterhead was manufactured and 19 cases of full-scale tunneling tests were performed each in 87.5 ㎥ volume of artificial rock mass. The relationships between advance rate and machine data were effectively analyzed by performing the tests in homogeneous rock mass with 70 MPa uniaxial compressive strength according to the TBM operational parameters such as thrust force and RPM of cutterhead. The utilization of the recorded penetration depth and torque values in the development of models is more accurate and realistic since they were derived through real excavation mechanism. The relationships between normal force on single disc cutter and penetration depth as well as between normal force and rolling force were suggested in this study. The prediction of advance rate and design of TBM can be performed in rock mass having 70 MPa strength using these relationships. An effort was made to improve the application of the developed model by applying the FPI (Field Penetration Index) concept which can overcome the limitation of 100% RQD (Rock Quality Designation) in artificial rock mass.

The Landscape Organization of the Dodong-SeoWon in the Aesthetics of Moderation (중용(中庸)의 미학으로 살핀 도동서원(道東書院)의 경관짜임)

  • Rho, Jae-Hyun;Shin, Byung-Chul
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.30 no.4
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    • pp.44-55
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    • 2012
  • This study is to interpret how landscape aesthetic characteristics of moderation, which is the point of human-oriented neo-confucianism vision, are projected to the landscape organization of a Dodong-SeoWon, known for its overflow to neo-confucianism grounds and standards among domestic SeoWon. The aspects of neo-confucianism discussion in the shape of Dodong-SeoWon with the beauty of from and contents dominating the landscape of Dodong-SeoWon different from constructive completeness as 7 external and internal landscape organization including placement, circulation, setting, vista, fencing, naming, and decoration are as follows. The left direction of Dodong-SeoWon, part of external organization, is the result of landscape organization that emphasized the stage of moderation through the unification of man and nature by naturalizing natural direction to human-oriented directions. Important aspects to rule external orders and standards of Dodong-SeoWon are principles of one classes based on ranks and bilateral symmetry that is the unity of setting and circulation landscape organization from penetrating the spirit of moderation with no bias. By securing territoriality by fencing the unity of verticality and horizontality, the landscape organization to reach moderation is expressed. Meanwhile, Suwoloo(水月樓) perceived on the floor of central assembly hall, the formation of time frame from roof piles of Hwanjumun(喚主門) as well as pilars of Jungjeongdang(中正堂), and rime link method inducing visual balance and openness through segment, combination, and others are vista organization that show the ideality of unique neo-confucianism building. Also as part of landscape organization contents. semantically, building name including arrangement from Taegukdoseol, ideological naming following the name of Ssanggye-SeoWon, which is the former body, the name of the hall symbolizing the transfer of neo-confucianism enlightenment, impartiality with no bias, as well as Geoinjae(居仁齋) and Geoijae(居義齋) based on olympic, are also results of applying neo-confucianism standards. Additionally. the SeoHoe(瑞花) expressing the change of IleumIlyang(一陰一陽) on the stylobate of Jungjeongdang, Saeho(細虎) which goes up and down, as well as Simul made of four dragons, are artistic expression of the moderation that symbolizes the harmony of ying and yang with no exceeding or insufficiency. Humorous and unique rocks and stones evenly arranged in all spots of Dodong-SeoWon are to promote anti-strict organization by offsetting the image and external order of the lecture hall as strict as it is, and this is very ironic as it is the other landscape organization in different dimension as well as the expression of moderation.

Appearance Rates of Several Substances into Cerebrospinal Fluid of Histamine-treated Rabbits (히스타민 투여시 토끼 뇌척수액으로의 물질 출현율)

  • Kim, Won-Shik;Shin, Dong-Hoon
    • The Korean Journal of Physiology
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    • v.2 no.2
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    • pp.21-31
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    • 1968
  • The appearance rates of antipyrine and urea into cerebrospinal fluid from blood were studied in the rabbits which were in the state of hypotension and of high permeability in the capillary beds following injection of histamine. The alteration in the distribution of electrolytes among various compartments of the brain and the permeability characteristics in the blood-cerebrospinal fluid barrier were also observed. Adult male rabbits, weighing around 2 kg, were used. Twenty four rabbits were divided into 3 groups. Besides the control group, histamine treated rabbits were categorized into 2 groups. $H_1$ consisted of the rabbits showing moderate responses to histamine and ranging from 62 to 80 mmHg in their mean anterial blood pressure. The animals which belong to $H_2-group$ showed severe responses to histamine and the mean anterial blood pressures dropped to 30-50 mmHg. Animals were anesthetized with nembutal, 30mg/kg i.v. The mean arterial blood pressure was read by means of the mercury manometer connected to the femoral artery. The animals, treated with histamine, were kept in hypotensive state at least for 40 minutes before the administration of the test-substances. The test-substances, 300 mg of urea and 200 mg of antipyrine, were dissolved in 3 ml of distilled water and were injected into the ear vein of the rabbit. After 10 minutes elapsed arterial blood sample was taken from the femoral artery and cerebrospinal fluid from the cisterna magna. Brain tissues were also analysed with respect to electrolytes in order to observe the disturbances in the electrolytes balance as well as in the function of the central nervous system. The results obtained were as follow: 1. The ratio of antipyrine concentration in cerebrospinal fluid to that of arterial blood plasma, that was the distribution ratio, was close to unity, revealing a well established equilibrium between the compartments of blood and cerebrospinal fluid in 10 minutes. In other words, there was no diffusion barrier with regard to antipyrine. The ratios over unity which were frequently seen in the histamine treated animals were attributable to the early penetration of the substance into the cerebrospinal fluid. 2. The appearance rates of urea into the cerebrospinal fluid in the histamine treated rabbits were higher in comparison with those of in the control animals. The increasing tendency in the rates was particularly remarkable in the $H_2-group$, showing the enhanced penetration of urea across the boondary. 3. In the htisamine treated $H_2-group$ the concentration of potassium in the blood plasma and cerebrospinal fluid well exceeded the control values and showed 8.5 and 9.0 mEq/l in average, respectively. Simultaneous drops in the brain tissue water were noticed, suggesting the leakage of intracellular potassium. 4. There was a coincidence in the rising pattern of potassium in the blood plasma and in the cerebrospinal fluid of $H_2-group$ and at least partial removal of the blood-cerebrospinal fluid barrier with respect to potassium was suggested in these animals. 5. The concentration of sodium in the blood plasma or in the cerebrospinal fluid showed no significant changes following histamine injection. However, sodium in the brain tissue revealed slight elevation in the histamine treated groups. 6. The ratios of the concentrations of potassium to those of sodium, [K]/[Na] in the brain tissues, were 1.92 in the control 1.82 in the $H_1$ and 1.52 in the $H_2-group$, respectively. The marked drop in the $H_2-group$ might represent neural dysfunction in the extremely hypotensive rabbits.

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Effects of Temperature on the Activity of Pulmonary Surfactant of the Rabbit (온도(溫度)가 가토(家兎) 폐포표면(肺胞表面) 활성물질(活性物質)의 활성도(活性度)에 미치는 영향(影響))

  • Kwon, Koing-Bo
    • The Korean Journal of Physiology
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    • v.7 no.2
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    • pp.1-8
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    • 1973
  • Though it has been reported by Clements et al. and Avery et al. that the activity of the pulmonary surfactant can be altered by the temperature changes, a conclusive evidence of the effects of temperature on the surfactant system of the lung is yet to come. In the present study, an attempt was made to observe possible effects of a few different degrees of temperature on the activity of the pulmonary surfactant of the rabbit in vivo and in vitro. The rabbit was sacrificed by blood shedding and both lungs were completely removed. The lung washings, obtained by gently lavaging the left lung with saline, was placed at 1) 4C for 1, 5, 10, 15, 30 and 40 days, and 2) 20C for 1, 2, 3, 4, 5 and 7 days for in vitro experiment. For in vivo experiment, the rabbit was placed at 4C for 4, 8, 12 and 24 hours, and the lung lavage was prepared as described above in the in vitro experiment. Tension-area (T-A) diagram of the lung lavage was recorded automatically by a modified. Langmuir-Wilhelmy balance with a synchronized recording system. The surface tensions thus obtained were compared with those of the normal rabbit, and the results are summarized as follows: 1. The maximal surface tension, minimal surface tension and stability index of the normal rabbit lung lavage were $52.5{\pm}2.3\;dynes/cm,\;4.9{\pm}2.3\;dynes/cm$ and 1.65, respectively. 2. In the group where the lung lavage was placed at 4C in vitro, the maximal and minimal surface tensions, and stability index did not show any noticeable changes comparing with the normal values up to 30 days. On the 40th day of the experiment, a tendency of a slight increase in the surface tensions was observed but the change was not significant. 3. When the lung lavage was placed at 20 C in vitro, the maximal surface tension did not show any appreciable change comparing with the normal except on the 7 th day with a slight increase. The minimal surface tension showed an increased value from the 2nd day, and on the 5 th and 7 th experimental day, markedly increased value was observed. The stability index, on the other hand. showed a marked decrease throughout the entire experiment with the value of 0.71 and 0.53 on the 5th and 7 th day, respectively. 4. In the group where the rabbit was placed at 4 C in vivo, the maximal surface tensions and stability index of the lung lavage showed little change from the normal. The minimal surface tension at 12 experimental hour showed a slight increase, but it returned to the normal value at 24 hour.

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A Study on the Characteristics of Museum Projects by Richard Meier (리챠드 마이어의 미술관 특성에 관한 연구)

  • 김용립
    • Archives of design research
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    • v.12 no.4
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    • pp.231-241
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    • 1999
  • This study propose to analyze the design method and the form elements of museums, of works by Richard Meier, and through the analysis, spacial characteristics of museums will be understood. The museum works of Richard Meier, as an exhibition space, not only display the art works efficiently, but they also offer visitors the opportunity to experience the art of architecture, as a cultural space. Richard Meier, when working on the projects, has utilized the design methods and the architectural language, learned from Mies van der Rohe and Le Corbusier, resourcefully. Having the structural grid as basis, the rational rectangular forms were intended for exhibition space, while the circular and partial circular forms of geometry were utilized in formative space. This was able to maintain the balance between functional and formative space. In the museums of his works, the ramp and the glass wall separated from the structure become very important means of expression. The ramps, not only make people to enjoy the interior and exterior of museum, but also able them to see the works of art from different distances and angles repeatedly and the large glass wall reveals the various shapes of interior to exterior. In comparing with the design method and language of two masters mentioned, the design principles and elements, developed by Meier were applied to the site plans, exhibition space planning and elevations to manifest its originality. The design concept, derived from the urban fabric and historical buildings around, gave harmony to the museum with its surroundings, and employing the deformed axis brought variation and the effect of diversion to the site plan. The exhibition space is much vitalized by the well arrangement of various exhibition fixtures in the museum. The exhibion fixtures, which the partitions, shelves, miches, and stages were put together in flexibility, play multiple roles as partitions dividing spaces, as furniture displaying art works, and as elements creating forms. The systematically arranged fixtures, also produce several visual axes and centers, which have visitors appreciate the works of art in various perspectives, hence create a unique environment.

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Determination of Energy Requirements for Maintenance in Hanwoo Steers (거세한우의 유지에너지 요구량 결정)

  • Kim, K.H.;Oh, Y.G.;Kim, W.;Lee, S.C.;Shin, K.J.;Jeon, B.T.
    • Journal of Animal Science and Technology
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    • v.46 no.2
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    • pp.193-200
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    • 2004
  • This experiment was carried out to determine energy requirements for maintenance of Hanwoo steers. Nine Hanwoo steers weighing 376.6$\pm$12.5kg were used in this experiment and fed rice straw(44%) and concentrate (56%) at three different energy levels; 0.8 times maintenance(0.8M), 1.2 times(1.2M) and 1.6 times(1.6M), respectively. Dry matter intake was 48.5, 65.9 and 86.5g/$BW^{0.75}$ for 0.8M, 1.2M and 1.6M, respectively. Increase in energy intake with the increased DM intake did not affect digestibilities of dry matter, organic matter, crude protein, crude fiber, crude fat and nitrogen-free extract. Gross energy intake averaged 190.8, 255.8 and 340.9kcal/BW0.75 for 0.8M, 1.2M and 1.6M, respectively. Energy loss was 41% feces and 0.6${\sim}$1.5% urine of gross energy intake. Further, energy loss from methane produced during rumen fermentation was 5${\sim}$9%, while body heat loss averaged 40${\sim}$60%. Intercept of the regression equation between ME intake and retained energy indicated that energy requirement for maintenance was 124.3kcal $ME/BW^{0.75}$.

Leaching behaviour of the herbicide mefenacet in the soil columns (토양 column중 제초제 mefenacet의 용탈)

  • Kim, Sung-Min;Kwon, Jeong-Wook;Ahn, Ki-Chang;Cho, Il-Kyu;Kyung, Kee-Sung;Lee, Jae-Koo
    • The Korean Journal of Pesticide Science
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    • v.7 no.3
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    • pp.176-181
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    • 2003
  • The leaching behaviour of [aniline-$^{14}C$]mefenacet in soil was investigated using glass columns (5 cm I.D. $\times$ 30 cm. H) packed with two types of soils with different physicochemical properties. $^{14}C$-Mefenacet (8.33 kBq) and mefenacet (in total, 1.05 mg/kg) were treated onto soil columns and rice plants (Oryza sativa L.) were grown for 17 weeks on these columns. Leachates from the columns were collected at the rate of 122.5 mL per week. $^{14}C$-Activities leached from soil A (OM, 3.1%; CEC, 86 mmol(+)/kg; texture, loam) columns with and without rice plants were 1.95 and 4.19% of the originally applied, whereas those from soil B (OM, 1.3%; CEC, 71 mmol(+)/kg; texture, loam) were 2.69 and 7.05%, respectively. These results indicated that larger amounts of $^{14}C$ were percolated from soil B with less organic matter and from the columns without vegetation. $^{14}C$-Activities absorbed by rice plants from soil A and B were 8.95 and 8.47%, respectively, most of which remained in the root and shoot excluding unhulled grains and ears without grains. $62\sim73%$ of the originally applied $^{14}C$ remained in the depth of $0\sim5cm$ in soil. The mass balance indicated that the losses by volatilization and/or mineralization amounted to $3.4\sim9.2%$ of the originally applied. $^{14}C$-Radioactivities in the aqueous phase of the leachates ranged from 59.4 to 97.7% of the radioactivities in leachates, showing the fast transformation of mefenacet to the polar metabolites.

EFFECT OF CANAL PREPARATION METHODS ON THE APICAL EXTRUSION OF DEBRIS (근관형성법이 근관잔Δ사의 치근단 정출에 미치는 영향)

  • Park, Ju-Myong;Kim, Sung-Kyo
    • Restorative Dentistry and Endodontics
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    • v.24 no.2
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    • pp.399-407
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    • 1999
  • Apical extrusion of canal debris is occurred inadvertently during root canal preparation and this could produce interappointment discomfort or postinstrumentation pain. The purpose of this study was to investigate the influence of canal preparation methods on the apical extrusion of canal debris by means of comparing the amounts of apically extruded debris with several kinds of instrumentation methods. In the first experiment, 40 incisors were divided into four groups of 10 each. They were instrumented using one of the four techniques: Step-back, crown-down pressureless technique with stainless steel K-files, engine-driven instrumentation with Quantec series 2000, and Profile .04 taper series 29. Root canal irrigation was done with 2.52% sodium hypochlorite solution. In the second experiment, 80 incisors were divided into five groups of 16 each and instrumented using step-back, crown-down pressureless technique with stainless steel K-files, engine-driven instrumentation such as Quantec SC, Quantec LX, and Profile .04 taper series 29 No irrigation procedure was performed in this second experiment. Extruded debris from each tooth was collected in a container and weighed by the use of an electronic balance after desiccation. With or without canal irrigation, step-back technique produced significantly more amount of apical debris than the other groups (p<0.05). However, there was no significant difference among crown-down pressureless technique, engine-driven instrumentation with Quantec LX, Quantec SC, or Profile. Therefore, either by hand or engine-driven instrumentation, it is concluded that to minimize apical debris, techniques using reaming motion of files should be applied rather than filing motion.

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Human Thermal Sensation and Comfort of Beach Areas in Summer - Woljeong-ri Beach, Gujwa-eup, Jeju-si, Jeju Special Self-Governing Province - (여름철 해변지역의 인간 열환경지수 및 열쾌적성 - 제주특별자치도 제주시 구좌읍 월정리 해변 -)

  • Park, Sookuk;Sin, Jihwan;Jo, Sangman;Hyun, Cheolji;Kang, Hoon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.4
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    • pp.100-108
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    • 2016
  • The climatic index for tourism(CIT) has recently been advanced, which includes complete human energy balance models such as physiological equivalent temperature(PET) and universal thermal climate index(UTCI). This study investigated human thermal sensation and comfort at Woljung-ri Beach, Jeju, Republic of Korea, in spring and summer 2015 for landscape planning and design in beach areas. Microclimatic data measurements and human thermal sensation/comfort surveys from ISO 10551 were conducted together. There were 869 adults that participated. As a result, perceptual and thermal preference that consider only physiological aspects had high coefficients of determination($r^2$) with PET in linear regression analyses: 92.8% and 87.6%, respectively. However, affective evaluation, personal acceptability and personal tolerance, which consider both physiological and psychological aspects, had low $r^2s$: 60.0%, 21.1% and 46.4%, respectively. However, the correlations between them and PET were all significant at the 0.01 level. The neutral PET range in perceptual for human thermal sensation was $25{\sim}27^{\circ}C$, but a PET range less or equal to 20% dissatisfaction, which was recommended by ASHRAE Standard 55, could not be achieved in perceptual. Only PET ranges in affective evaluation and personal tolerance affected by both aspects were qualified for the recommendation as $21{\sim}32^{\circ}C$ and $17{\sim}37^{\circ}C$, respectively. Therefore, the PET range of $21{\sim}32^{\circ}C$ is recommended to be used for the human thermal comfort zone of beach areas in landscape planning and design as well as tourism and recreational planning. PET heat stress level ranges on the beach were $2{\sim}5^{\circ}C$ higher than those in inland urban areas of the Republic of Korea. Also, they were similar to high results of tropical areas such as Taiwan and Nigeria, and higher than those of western and middle Europe and Tel Aviv, Israel.