• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.1
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• pp.11-24
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• 1979

To characterize elastic and plastic chilling injury, rice seedlings grown at 28/$16^{\circ}C$ day/night temp. under 20K lux (13hrs.) in a phytotron were subjected to a 11/$6^{\circ}C$, 20K lux condition for 2, 4, 6 or 8 days at 1, 2, 3, 4 or 5th leaf-stage, respectively, followed by further growth under 28/$16^{\circ}C$condition till 30th day after seeding. Japonica variety Jinheung and Chulwon No.1 survived almost 100% without any significant , discoloration and death of leaves due to chilling even under the chilling of 8 days at all seedling ages tested. Tongil and Yushin, varieties from Indica x Japonica cross, showed increasing discoloration of leaves and death of plants with increase in chilling intensity. The longest chilling duration shown seedling death less than 5% was 4, 6, 1, 4, 8 days for Tongil, and 6, 6, 1, 2, 2, days for Yushin at 1, 2, 3, 5th leaf-stage, respectively. The degree of discoloration and death of leaves or suppression of height growth was not explicitly related to seedling death or the dry weight reduction. The degree of seedling death or dry weight reduction could differentiate chilling tolerance of varieties and seedling ages, but somewhat differently. Reduction in dry weight due to chilling occurred even without any visible injury or seedling death. These suggest that both the degree of seedling death and reduction in dry weight should be considered in the test of varieties for chilling tolerance. Combined evaluation of seedling death and dry weight reduction indicated the most susceptible seedling age to chilling injury to be 1 to 2nd leaf-stage for Jinheung, 2 to 3rd leaf-stage for Chulwon No.1, 3rd leaf- stage for Tongil and Yushin, respectively.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.111-124
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• 2010

To monitor the environment of land surface change is considered as an important research field since those parameters are related with land use, climate change, meteorological study, agriculture modulation, surface energy balance, and surface environment system. For the change detection, many different methods have been presented for distributing more detailed information with various tools from ground based measurement to satellite multi-spectral sensor. Recently, using high resolution satellite data is considered the most efficient way to monitor extensive land environmental system especially for higher spatial and temporal resolution. In this study, we use two different spatial resolution satellites; the one is SPOT/VEGETATION with 1 km spatial resolution to detect coarse resolution of the area change and determine objective threshold. The other is Landsat satellite having high resolution to figure out detailed land environmental change. According to their spatial resolution, they show different observation characteristics such as repeat cycle, and the global coverage. By correlating two kinds of satellites, we can detect land surface change from mid resolution to high resolution. The K-mean clustering algorithm is applied to detect changed area with two different temporal images. When using solar spectral band, there are complicate surface reflectance scattering characteristics which make surface change detection difficult. That effect would be leading serious problems when interpreting surface characteristics. For example, in spite of constant their own surface reflectance value, it could be changed according to solar, and sensor relative observation location. To reduce those affects, in this study, long-term Normalized Difference Vegetation Index (NDVI) with solar spectral channels performed for atmospheric and bi-directional correction from SPOT/VEGETATION data are utilized to offer objective threshold value for detecting land surface change, since that NDVI has less sensitivity for solar geometry than solar channel. The surface change detection based on long-term NDVI shows improved results than when only using Landsat.

• The korean journal of orthodontics
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• v.32 no.4 s.93
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• pp.293-300
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• 2002

The purpose of this study was to evaluate the clinical effectiveness of hydrophilic primer, which claim to retain adequate bond strength on moistened enamel resulting from moisture or saliva contamination, by comparing the shear bond strength and adhesive failure patterns of brackets bonded using hydrophilic primer and conventional hydrophobic primer. Brackets were bonded to human premolars embedded in metal cylinders utilizing light cured adhesive, primed with either a hydrophilic primer(Transbond fm primer) or a conventional hydrophobic primer(Transbond XT primer). Each sample was exposed to varying degrees of artificial saliva contamination during the priming process. The shear bond strength was measured using a universal testing machine, and the adhesive failure patterns after debonding were visually examined by strereomicroscope and assessed using the adhesive remnant index(ARI). The results were as follows 1. In dry conditions, no significant differences in shear bond strength between Transbond W and Transbond XT primers were found. 2. Transbond MIP primer exhibited a significantly higher shear bond strength than Transbond XT primer in saliva-contaminated conditions, regardless of the degree of contamination. 3. When contaminated with one coat of saliva, Transbond MIP primer did not exhibit significant differences in shear bond strength compared to the dry condition. When contaminated with two coats of saliva, Transbond MIP primer exhibited a singnificantly lower shear bond strength compared to the dry condition. 4. The adhesive remnant index of the adhesive failure pattern had a tendency to decrease, as the degree of saliva contamination increased. Bracket-adhesive interface failure was observed in more than half of the saliva contaminated samples utilizing Transbond MIP primer, whereas the bond failure sites of the Transbond XT primer samples occurred almost exclusively at the adhesive-enamel interface in saliva-contaminated conditions. The results of this study suggest that in cases where moisture control is difficult, Transbond MIP primer is an effective alternative to conventional hydrophobic primers.

• Journal of Korea Spatial Information System Society
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• v.6 no.1 s.11
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• pp.101-117
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• 2004

Standards are essential to facilitate the efficient use of GIS data. International Standards such as ISO TC211's 19100 series and various technical specifications from OpenGIS Consortium are some of the examples of efforts to maintain the interoperability among GIS applications. Marine GIS is no exception to this rule and in this context. developing standards for marine GIS is also in urgent needs. Using the same meaning and definition for the features commonly found in marine GIS applications is one of the ways to increase the interoperability among systems. One of the key requirements for maintaining the standard meanings for features is to build a common feature catalogue. This paper examines the concept of feature catalogue and describe the ways in which the feature catalogue can be organized. To identify the common features found in various marine GIS applications, a comprehensive search has been made to collect and analyze the features used in various applications. To maintain the interoperability with the National GIS (NGIS) system, the features used in various NGIS applications have been analyzed as well. The result of these analyses are used to create a comprehensive list of common features for marine GIS. This paper then explains the common feature catalogue for marine GIS and the provides the appropriate classification and coding systems for the common features. In addition, a registration tool for registering the common features into the standard registry has been developed in this study. This Web-based tool can be used to input features into the feature catalogue by various applications and also to maintain a standard-compliant feature catalogue by standard agencies.

• Korean Journal of Environmental Biology
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• v.20 no.3
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• pp.205-215
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• 2002

Effects of artificial and solar W-B radiation on five rhodophytes (Curdiea racovitzae, Gigaytina skottsbergii, Mazzaella obovata, Myriogramme manginii, Palmaria decipiens) from Antarctica have been investigated using PAM fluorescence in laboratory and in the field. Laboratory studies showed that there were significant differences in the UV sensitivity between different species, and that the differences appeared to be correlated with the depth of collection of the specimens. It was apparent from the observations that the samples such as M. manginii and P. decipiens collected from 20-30 m depths were move sensitive to W-B radiation compared with those collected from shallower depths, The present study confirmed that an acclimation to the surrounding light regime could be an important factor to determine the UV-sensitivity of a species or individuals and that PAM measurements are rapid and non-destructive methods to evaluate UV influences. From field studies on M. manginii and P. decipiens it was observed that both plants exhibited changes in the effective quantum yield, with the minimum values nt noon followed by n recovery in the evening. Photoinhibition occurred in these species could therefore be accounted for by so- called dynamic photoinhibition. It seems likely that this protective mechanism may contribute to survival of the species in shallow water where they may encounter intense solar radiation. The presence or absence of the W- B component under solar radiation differently affected the photosynthetic recovery process, and the rate of recovery was much stoney in UV- present than in W- absent conditions. Functional role of W- B appears to delay the recovery of photosynthesis in the studied macroalgae. Differential sensitivity to UV-B recognised between M. manginii and P. decipiens seemed to correspond well with the amount of UV-absorbing substances (UVAS) contained in the respective species. Higher tolerance to solar radiation by the latter species may be due to the higher amount of UVAS. There were variations of UVAS concentrations in algal thalli depending on the season and depth of collection.

• Horticultural Science & Technology
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• v.34 no.4
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• pp.596-606
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• 2016

The growth and contents of anthocyanins and ascorbic acid in lettuce(Lactuca sativa L., 'Jeokchima') as affected by supplemental UV-A LED irradiation under different light quality and photoperiod conditions were analyzed in this study. Five light qualities, namely B (blue LED), R (red LED), BUV (blue LED+UV-A LED), RUV (red LED+UV-A LED) and Control (white fluorescent lamps) with photoperiods of 12/12 hours (day/night), 16/8 hours, or 20/4 hours were provided to investigate the effects of light quality and photoperiod on the growth and accumulation of anthocyanins and ascorbic acid in lettuce leaves. As measured 28 days after transplanting, the number of leaves, leaf length, leaf width, leaf area, shoot fresh weight and dry weight of lettuce were significantly affected by light quality and photoperiod. The number of leaves, leaf length, leaf width, leaf area, shoot fresh weight and dry weight of lettuce grown under R treatment increased with increasing light period. By contrast, leaf development was inhibited, but chlorophyll content increased, under B treatment. Supplemental UV-A irradiation significantly decreased leaf length, leaf width, leaf area and shoot fresh weight. Anthocyanins in lettuce increased significantly with decreasing dark period under B treatment. A synergistic effect of supplemental UV-A LED irradiation on anthocyanins accumulation was found for lettuce leaves grown under R treatment but not B treatment. Ascorbic acid in lettuce was greatly affected by photoperiod. Ascorbic acid content at BUV and RUV treatments increased by 20-30% compared to without UV-A LED irradiation. From these results, it was concluded that growth and contents of anthocyanins and ascorbic acid in lettuce are significantly affected by supplemental UV-A LED irradiation. The results obtained in this study will be informative for efforts to improve the nutritional value of leafy vegetables grown in plant factories.

• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.93-100
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• 2011

Maintenance of adequate soil water potential during the period of crop growth is necessary to support optimum plant growth and yields. A better understanding of soil water movement within and below the rooting zone can facilitate optimal irrigation scheduling aimed at minimizing the adverse effects of water stress on crop growth and development and the leaching of water below the root zone which can have adverse environmental effects. The objective of this study was to evaluate the feasibility of using a portable irrigation controller with an Watermark sensor for the cultivation of drip-irrigated vegetable crops in a greenhouse. The control capability of the irrigation controller for a soil water potential of -20 kPa was evaluated under summer conditions by cultivating 45-day-old tomato plants grown in three differently textured soils (sandy loam, loam, and loamy sands). Water contents through each soil profile were continuously monitored using three Sentek probes, each consisting of three capacitance sensors at 10, 20, and 30 cm depths. Even though a repeatable cycling of soil water potential occurred for the potential treatment, the lower limit of the Watermark (about 0 kPa) obtained in this study presented a limitation of using the Watermark sensor for optimal irrigation of tomato plants where -20 kPa was used as a point for triggering irrigations. This problem might be related to the slow response time and inadequate soil-sensor interface of the Watermark sensor as compared to a porous and ceramic cup-based tensiometer with a sensitive pressure transducer. In addition, the irrigation time of 50 to 60 min at each of the irrigation operation gave a rapid drop of the potential to zero, resulting in over irrigation of tomatoes. There were differences in water content among the three different soil types under the variable rate irrigation, showing a range of water contents of 16 to 24%, 17 to 28%, and 24 to 32% for loamy sand, sandy loam, and loam soils, respectively. The greatest rate increase in water content was observed in the top of 10 cm depth of sandy loam soil within almost 60 min from the start of irrigation.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.2
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• pp.195-201
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• 2014

Body fluid has been studied for diverse fields like Ringer's solutions, artificial joint fluids, cell growth culture media because it plays a crucial role in controlling body temperature and acts as a solvent for diverse metabolite processes in the body and delivery media of mineral, energy source, hormone, signal and drug from and to cell via blood or lymphatic vessel by osmotic pressure or active uptake. Stratum corneum containing extracellular lipids and NMF (natural moisturizing factor) absorbs atmospheric water residing outside of cells and utilize it to hydrate inside of their own. This process is related to skin barrier function. In this study, we conducted the cell viability test with Cell Bio Fluid $Sync^{TM}$, which mimicks body fluids including amino acids, peptides, and monosaccharides to strengthen skin barrier, and the clinical skin improvement test with cosmetics containing Cell Bio Fluid $Sync^{TM}$. In the cell viability test, HaCaT cell was treated with PBS for 3 hours, followed by the treatment of a cell culture medium (DMEM) and isotonic solution (PBS) and Cell Bio Fluid $Sync^{TM}$ for 3 hours each. Then, MTT assay and image analysis were conducted. In the clinical skin improvement test, twenty-one healthy women participated. Participants applied cosmetics containing Cell Bio Fluid $Sync^{TM}$ on their face for a week and evaluated the skin hydration, skin roughness, brightness and evenness. All measurements were conducted after they washed off their face and took a rest under the constant temperature ($22{\pm}2^{\circ}C$) and constant humidity conditions ($50{\pm}5%$) for 20 minutes. All the data were analyzed by SPSS (version 21) software program. Results showed that Cell Bio Fluid $Sync^{TM}$ improved both the cell viability and in vivo skin conditions such as skin hydration, roughness, brightness and evenness.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.1
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• pp.11-18
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• 2004

The eruption of permanent teeth represents the movement in the alveolar bone before appearance in oral cavity, to the occlusal plane after appearance in oral cavity, and additive movement after reaching th the occlusal plane. Tooth eruption is mostly controlled by genetic signals. The eruption stage is divided to preeruptive alveolar stage, alveolar bone stage, mucosal stage according to the process of growth and development. If the disturbance is occured in any stage of eruption, tooth does not erupt. The cause of eruption disturbance are ectopic position of the tooth germ, obstruction of the eruption path and defects in the follicle or PDL. In the treatment of eruption disturbance, surgical procedures are commonly used. There are three kind of surgical procedure ; surgical exposure, surgical repositioning, surgical exposure and traction Surgical exposure is basic procedure. This involves removal of mucosa, bone, lesion that are surrounding the teeth, dental sac when necessary to maintain a patent channel between the crown and the normal eruptive path into the oral cavity. To ensure this patency, many techniques including cementation of a celluloid crown, packing with gutta-percha or zinc oxide-eugenol, or a surgical pack, are used. When surgical exposure is conducted, operators should not expose any part of cervical root cement and not injure periodontium or root of adjunct tooth. After surgical exposure, tooth should be surrounded by keratinized gingiva. There is direct relationship between the extent of development of pathophysiologic aberrations and the intensity of the manipulative injury inflicted on the tooth by surgical treatment, so operator should consider this thing. In these cases, surgical exposure is conducted on Maxillary 1st milars that have a eruption disturbance and improve the eruption disturbance effectively.

• Horticultural Science & Technology
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• v.35 no.2
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• pp.178-187
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• 2017

The aim of this study was to investigate the effect of different light sources on the levels of glucosinolates (GSLs) in rocket salad (Eruca sativa L.). The light sources used in the study were: natural light (Control-1 or 2), red light-emitting diodes(LEDs), blue LEDs, mixed red and blue LEDs (R+B LEDs), white LEDs, fluorescent lamps (FL), and fluorescent lamps plus UV-C (FL+UV-C). Two separate experiments were conducted [Experiment I: Control-1, Red LED, Blue LED, Mix (R+B) LED and Experiment II: Control-2, White LED, FL, FL+UV-C] because of the limited number of growth chambers in our laboratory. The rate of increase in the length of rocket salad leaves was the highest under red LEDs and, FL confirming that red LED and, FL affect the growth of rocket salad. We separated and identified seven types of GSLs from the rocket salad:glucoraphanin, diglucothiobeinin, glucoerucin, glucobrassicin, dimeric 4-mercaptobutyl GSL, 4-methoxyglucobrassicin, and gluconasturtiin. The highest total GSL contents in Eexperiment I was found in plants grown under in red LEDs ($4.30{\mu}mol{\cdot}g^{-1}\;dry$ weight, DW), and the lowest under blue LEDs ($0.17{\mu}mol{\cdot}g^{-1}\;DW$). The highest total GSL contents in Experiment II was found in plants grown under FL ($13.45{\mu}mol{\cdot}g^{-1}\;DW$), and the lowest in FL+UV-C ($0.39{\mu}mol{\cdot}g^{-1}\;DW$). Especially in Experiment II, the content of dimeric 4-mercaptobutyl, which has a strong aroma and spicy flavor in rocket salad, was higher under FL and white LEDs than in Control-2, increasing by approximately 14.9 and 3.2-fold respectively. Therefore, light sources such as red LEDs, white LEDs and FL affected the accumulation of GSLs in rocket salad.