• Economic and Environmental Geology
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• v.53 no.1
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• pp.23-32
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• 2020

Geological CO₂ sequestration is a global warming response technology to limit atmospheric emissions by injecting CO₂ captured on a large scale into deep geological formations. The presented results concern mineralogical and hydrogeological investigations (FE-SEM, XRD, XRF, and MICP) of mudstone samples from drilling cores of the Pohang basin, which is the research area for the first demonstration-scale CO₂ storage project in Korea. They aim to identify the mineral properties of the mudstone constituting the caprock and to quantitatively evaluate the hydrogeologic sealing capacity that directly affects the stability and reliability of geological CO₂ storage. Mineralogical analysis showed that the mudstone samples are mainly composed of quartz, K-feldspar, plagioclase and a small amount of pyrite, calcite, clay minerals, etc. Mercury intrusion capillary pressure analysis also showed that the samples generally had uniform particle configurations and pore distribution and there was no distinct correlation between the estimated porosity and air permeability. The allowable CO₂ column heights based on the estimated pore-entry pressures and breakthrough pressures were found to be significantly higher than the thickness of the targeting CO₂ injection layer. These results showed that the mudstone layers in the Yeongil group, Pohang basin, Korea have sufficient sealing capacity to suppress the leakage of CO₂ injected during the demonstration-scale CO₂ storage project. It should be noticed, however, that the applicability of results and analyses in this study is limited by the lack of available samples. For rigorous assessment of the sealing efficiency for geological CO₂ storage operations, significant efforts on collection and multi-aspect evaluation for core samples over entire caprock formations should be accompanied.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.427-433
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• 2014

Trellising is an important cultural practice that affects grape quality and yield. Some grape cultivars require different trellising under different climate and soil conditions. To find suitable trellis conditions for grape cultivar 'Cheongsoo', we measured growth and fruit characteristics with three different trellis systems: curtain, Geneva double curtain (GDC), and modified T. The maximum light exposure of clusters in the curtain, GDC, modified T trellis systems was 670, 1,654, and $1,649{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, respectively. However, there was no difference in air temperature among the three trellis systems. Net $CO_2$ assimilation rate at $1,500{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ light intensity was 13.4, 13.7, and $8.7{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ in curtain, GDC, and modified T trellis systems, respectively. Trunk cross section area (TCSA) and bud burst rate were not significantly different among the three systems. Shoot number was 31.3, 47.0, and 37.0 in curtain, GDC, and modified T trellis systems, respectively. The shoot length was higher (243.9 cm) in the modified T trellis system than in the single curtain (171.1 cm) and GDC (151.5 cm) systems. Interior leaf number and leaf layer number were higher in the GDC system, in which there are two primary branches, in comparison to the modified T and curtain systems, which utilize one primary branch. Primary leaf area and lateral leaf area were significantly higher in the modified T trellis system in comparison to the GDC system. Berry weight, length and diameter, and total soluble solids were not significantly different among the three trellis systems. However, cluster weight and cluster number per tree were significantly higher in GDC. Titratable acidity was significantly lower in GDC. Collectively, our data suggest that the GDC trellis system is preferable for grape 'Cheongsoo' to maintain fruit quality and quantity in Korea.

• Journal of Chest Surgery
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• v.39 no.9 s.266
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• pp.659-667
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• 2006

Background: Experimental studies of vascular remodeling in the pulmonary arteries have been performed actively. These models required a persistent vascular insult for intimal injury induced by chronic hypoxia, monocrotaline intoxication or chronic air embolism and characterized medial hypertrophy and neointimal formation by active synthesis of the extracellular matrix protein. The purpose of this study was to determine the pattern of pulmonary vascular remodeling after obstruction of the pulmonary vein. Material and Method: Obstruction of the right pulmonary vein with a metal clip was performed in Sprague-Dawley rats $(352{\pm}18g,\;n=10)$ to cause pulmonary vascular disease. Fifteen days later, experimental studies were done and finally the both lungs and hearts were extirpated for experimental measurement. Pulmonary arterial pressure, weight ratio of right ventricle (RV) to left ventricle (LV) and ventricular septum (S) (RV/LV +S weight ratio), and pulmonary artery morphology (percent wall thickness, %WT) were evaluated and compared with normal control groups. Result: Pulmonary hypertension $(38{\pm}12mmHg\;vs\;13{\pm}4mmHg;\;p<0.05)$ and right ventricular hypertrophy (right ventricular/left ventricular and septal weight ratio, $0.52{\pm}0.07\;vs\;0.35{\pm}0.04;\;p<0.05$) with hypertrophy of the muscular layer of the pulmonary arterial wall (percent wall thickness, $22.4{\pm}6.7%\;vs\;6.7{\pm}3.4%;\;p<0.05$) were developed by 15 days after obstruction of the pulmonary vein. Conclusion: Obstruction of the pulmonary vein developed elevation of pulmonary blood pressure and medial hypertrophy of the pulmonary artery. These results are a part of the characteristic vascular remodeling. Theses results demonstrate that obstruction of the pulmonary vein can develope not only high pulmoanry blood flow of contralateral lung but also intima injury inducing vascular remodeling.

• KSBB Journal
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• v.29 no.4
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• pp.285-296
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• 2014

Although the problems of the algal blooms have been world-widely observed in freshwater, estuary, and marine throughout the year, it is not yet certain what are the basic causes of such blooms. Consequently, it is very difficult to predict when and where algal blooms occur. The constituents of the Asian dust are in a good agreement with the elements required for the algal growth, which suggests some possible relationship between the algal blooms and the Asian dust. There have been frequently algal blooms in drinking water from rivers or lakes. However, there is no any algal blooms in upwelling waters where the Asian dust cannot penetrate into the soil due to its relatively weak settling velocity (size of particles, $4.5{\pm}1.5{\mu}m$), which implies the possible close relationship of the Asian dust with algal blooms. The present initiative study is thus intended firstly in Korea to illustrate such a relationship by reviewing typical previous studies along with 12 years of weekly iron profiles (2001~2012) and two slant culture experiments with the dissolved Asian dust. The result showed bacterial suspected colonies in the slant culture experiment that are qualitatively in a good agreement with the recent Japanese studies. Since the diatoms require cheap energy (8%) compared to other phytoplankton (100%) to synthesize their cell walls by silicate, the present results can be used to predict algal blooms by diatoms if the concentrations of iron and silicate are available during spring and fall. It can be postulated that the algal blooms occur only if the environmental factors such as light, nutrients, calm water surface layer, temperature, and pH are simultaneously satisfied with the requirements of the micronutrients of mineral ions supplied by the Asian dust as enzymatic cofactors for the rapid bio-synthesis of the macromolecules during algal blooms. Simple eco-friendly methods to regulate the algal blooms are suggested for the initial stage of blooming with limited area: 1) to cover up the water surface with black curtain and inhibit photosynthesis during the day time, 2) to blow air (20.9%) or pure oxygen into the bottom of the water and inhibit rubisco for carbon uptake and nitrate reductase for nitrogen uptake activities in algal growth during the night, 3) to eliminate the resting spores or cysts by suction of bottom sediments as deep as 5 cm to prevent the next year germinations.

• Journal of the Society of Disaster Information
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• v.11 no.1
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• pp.135-147
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• 2015

Recent underground common utility tunnels are underground facilities for jointly accommodating more than 2 kinds of air-conditioning and heating facilities, vacuum dust collector, information processing cables as well as electricity, telecommunications, waterworks, city gas, sewerage system required when citizens live their daily lives and facilities responsible for the central function of the country but it is difficult to cope with fire accidents quickly and hard to enter into common utility tunnels to extinguish a fire due to toxic gases and smoke generated when various cables are burnt. Thus, in the event of a fire, not only the nerve center of the country is paralyzed such as significant property damage and loss of communication etc. but citizen inconveniences are caused. Therefore, noticing that most fires break out by a short circuit due to electrical works and degradation contact due to combustible cables as the main causes of fires in domestic and foreign common utility tunnels fire cases that have occurred so far, the purpose of this paper is to scientifically analyze the behavior of a fire by producing the model of actual common utility tunnels and reproducing the fire. A fire experiment was conducted in a state that line type fixed temperature detector, fire door, connection deluge set and ventilation equipment are installed in underground common utility tunnels and transmission power distribution cables are coated with fire proof paints in a certain section and heating pipes are fire proof covered. As a result, in the case of Type II, the maximum temperature was measured as $932^{\circ}C$ and line type fixed temperature detector displayed the fire location exactly in the receiver at a constant temperature. And transmission power distribution cables painted with fire proof paints in a certain section, the case of Type III, were found not to be fire resistant and fire proof covered heating pipes to be fire resistant for about 30 minutes. Also, fire simulation was carried out by entering fire load during a real fire test and as a result, the maximum temperature is $943^{\circ}C$, almost identical with $932^{\circ}C$ during a real fire test. Therefore, it is considered that fire behaviour can be predicted by conducting fire simulation only with common utility tunnels fire load and result values of heat release rate, height of the smoke layer, concentration of O2, CO, CO2 etc. obtained by simulation are determined to be applied as the values during a real fire experiment. In the future, it is expected that more reliable information on domestic underground common utility tunnels fire accidents can be provided and it will contribute to construction and maintenance repair effectively and systematically by analyzing and accumulating experimental data on domestic underground common utility tunnels fire accidents built in this study and fire cases continuously every year and complementing laws and regulations and administration manuals etc.

• Applied Biological Chemistry
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• v.32 no.2
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• pp.104-108
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• 1989

A 2.5 ton scale of solar energy concentration blast-grain circulation dryer (SECD) was developed in order to shorten the drying time without damaged paddy. Comparative experiments were carried out on performance, drying efficiency, consistency in moisture content, milling recovery, grade of milled rice, and energy requirement and cost against all that of in-bin drying and storage (IBDS) method. The experiments were performed using mixture of several rice varieties of Tongil type(Japonica-Indica breeding type) under the autumn weather in Korea. The circulating air temperature inside SECD was $4{\sim}5^{\circ}C$ higher than that of IBDS. The moisture content of the paddy during the drying period in SECD was uniform while substantially varied in upper, middle or bottom layer in IBDS. By SECD, 24% initial moisture content of paddy was reduced to 15% after only 3 days of drying as compared to 14 days at IBDS. The percentage of cracked kernels in upper, middle and bottom layers in IBDS was 6, 6 and 12%, respectively, whereas 7% in all layers in SECD. Both types of dryers did not significantly affect the milling recovery of dried paddy and grade of milled rice. Energy requirement of SECD(28.8Kw/2.5ton) for paddy drying was much less than that of IBDS(108Kw/2.5ton).

• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.161-165
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• 2000

Spectroradiometric light transmittance from 300 to 1,100nm in the greenhouse covered with the CEM BIO polyethylene film was greater than that in the greenhouse covered with polyethylene film (control). As a whole, solar radiation transmittance into greenhouse was a half level, due to shades caused by double layer covering, frame and equipment. Net radiation energy emitted throughout surface of the greenhouse covered with CEM BIO polyethylene film was 5,424.5W.m$^{-2}$ , which was lower by 2.9% as compared to that of the greenhouse covered with polyethylene film. Photosynthetically active radiation from 400 to 700nm of the greenhouse covered with CEM BIO polyethylene film was 3,861.2W.m$^{-2}$ , which was higher by 3.8% as compared to hat of the greenhouse covered with polyethylene film. Accumulated minimum air temperature from Oct. 7, 1997 to Oct. 16, 1997 of the greenhouse covered with CEM BIO polyethylene film was 100.5$^{\circ}C$, which was higher by 2.5$^{\circ}C$ as compared to that of the greenhouse covered with polyethylene film. As results, height, stem diameter, leaf count, leaf area, fresh weight and dry weight of green pepper plants and canopy production structure measured at 30 days after transplanting were enhanced. Mean fruit weight n the greenhouse covered with CEM BIO polyethylene film was 11.28 g and 1.25 g greater as compared to that in the greenhouse covered with polyethylene film, due to increased fruit diameter and flesh thickness. Percent marketable fruits produced in the greenhouse covered with CEM BIO polyethylene film were 96.1%, and was greater by 2.7% thant that of the greenhouse covered with polyethylnee film due to decreased infection, sterility, severe curve and twisted fruits. The green pepper yield of the greenhouse covered with CEM BIO polyethylene film from Nov. 19, 1997 to Feb. 3, 1998 was greater by 974 kg per hectare than that of the greenhouse covered with polyethylene film, but the total fruit had no difference.

• Journal of the Korean Electrochemical Society
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• v.10 no.4
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• pp.283-287
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• 2007

KIER has been developing the anode-supported flat tubular solid oxide fuel cell unit bundle for the intermediate temperature($700{\sim}800^{\circ}C$) operation. Anode-supported flat tubular cells have Ni/YSZ cermet anode support, 8 moi.% $Y_2O_3$ stabilized $ZrO_2(YSZ)$ thin electrolyte, and cathode multi-layer composed of Sr-doped $LaSrMnO_3(LSM)$, LSM-YSZ composite, and $LaSrCoFeO_3(LSCF)$. The prepared anode-supported flat tubular cell was joined with ferritic stainless steel cap by induction brazing process. Current collection for the cathode was achieved by winding Ag wire and $La_{0.6}Sr_{0.4}CoO_3(LSCo)$ paste, while current collection for the anode was achieved by using Ni wire and felt. For making stack, the prepared anode-supported flat tubular cells with effective electrode area of $90\;cm^2$ connected in series with 12 unit bundles, in which unit bundle consists of two cells connected in parallel. The performance of unit bundle in 3% humidified $H_2$ and air at $800^{\circ}C$ shows maximum power density of $0.39\;W/cm^2$ (@ 0.7V). Through these experiments, we obtained basic technology of the anode-supported flat tubular cell and established the proprietary concept of the anode-supported flat tubular cell unit bundle.

• 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.

• Applied Microscopy
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• v.36 no.1
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• pp.35-45
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• 2006

Plants of Vitex negundo are known to develop numerous trichomes throughout their body, where certain trichome types have been believed to be one of the plausible structures for the unique scents. In the current study. structural aspects of the trichomes have been examined in leaves and stems of Vitex negundo using TEM and SEM. Trichome types as well as structural changes that occurred in certain trichomes during secretion have been mainly focused. Three type of glandular trichomes and two types of non-glandular trichomes were developed in the epidermis of young and mature Vitex negundo plants. The glandular trichomes included the peltate type (Type 1), the capitate type (Type 2), and degraded capitate type (Type 3), whereas the non-glandular warty trichomes contained the multicellular (Types 4) and unicellular type (Type 5). Type 1 and 2 consisted of head and stalk cells, but their number and size were different. One secretory cavity was formed from the four head cells in the former, but only two head cells were involved in the latter. The cytoplasmic density in the head cell was quite high and in particular, sER and Golgi bodies were well developed. At initiation of their development, the cuticle layer of the head cells separated from the outer tangential wall to form a secretory cavity. Subsequently the cavity expanded acropetally and a large number of secretory vesicles continuously produced from the head cells until they filled the entire cavity. The cavity contained materials that would be soon discharged into intercellular spaces and/or into the air. The cavity began to decrease the volume by contracting at initial secretion but degrade rapidly within short time. It has been suggested that the mode of secretion in V. negundo is probably the eccrine secretion, since no break or rupture of the cavity has been observed during examination. Contrastingly Type 3 exhibited deterioration of the head cell at early stage. Type 4 was about $110{\sim}190{\mu}m$ long, consisting of $2{\sim}3$ cells, and distributed more in the adaxial epidermis compared to the abaxial surface. However, $20{\sim}30{\mu}m$ long Type 5 was extremely dense in both epidermis. Among several trichome types, Type 1 and 2 probably play an important role in discharging unique aromatic scents in plants of V. negundo.