• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.8-16
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• 1998

Sexual maturation and reproductive cycle of the goldeye rockfish, Sebastes thompsoni were investigated under photomicroscopy. Samples were collected monthly in the coastal water of Samcheonpo ($34^{\circ}55'N$ ), Korea from November 1995 to October 1996, The ovary consists of several ovarian lamellae originated from ovarian outer membrane. Oogonia which are originated from the inner surface of the ovarian lamella protrude to the ovarian cavity in oocyte stage, and they ave suspended by the egg stalk. The testis is seminiferous tubule type in internal structure. Seminiferous tubule consists of many testicular cysts which contain numerous germ cells in same developmental stage. Biological minimum size of female and male were 19.5 cm and 21.5 cm in total length, respectively. Gonadosomatic index (GSI) of female was the highest (9.56) in March and the lowest (0.15) in August. GSI of male was the highest (0.25) in February and the lowest (0.04) in July. Reproductive cycle was classified into the following successive stages: in female, growing (October and November), maturation ( $December\~February$), gestation (March), parturition and recovery ($April\~June$) and resting ($July\~September$), and in male, growing ($September\~November$), maturation ( December and January), ripe and copulation ( February and March) and degeneration and resting ($April\~August$).

• The Journal of Art Theory & Practice
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• no.5
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• pp.7-24
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• 2007

The subject is connected with a structure named "The Symbolic" to Lacan, but he denied that the subject is explained simply as a fruit of language and "Other". From his point of view, passing through Subject, De-formation and Crack over it is designated as foundation of generation and creation rather than our destined defect. It should not be understood that subject of "The Real" is a concept of the subject free itself from restraint of "The Symbolic". However, this does not mean he asserts "Subject" is something incapable of being controlled by the unknown power. The problem is that this autonomous existence meets inside of it with something "more than one's own self" by "circulating around itself" like a permanent star. This is the indication of a "stranger in the middle of my privacy", or "extimit$\'{e}$", a coined-word by Lacan. Perhaps "Subject" is nothing more than the name of distance of object which is "too hot" to come close, and of this circulating movement. It's because of this object that the real subject stands against generalization and the subject can't be restored to any place in symbolic order-even though it is empty. The part which is told from Lacan's structural theory, that is to say, an importance to Lacan is that his Subject theory is not suggested or denied as a manual structure. On the contrary, it is a study of the relationship between the settled symbol that included in "real subject which is a unconscious one" and the symbolic subject hold- that is a metaphysical subject in general meaning. In Lacan's enlarged concept of subject beyond symbolic reality, it is noticeable that it gives justifiability to the union of a medium of different nature in artistic expression. We can recognize that the unconscious world is a living space which enables it to be a "condition of human being", not something dark under the surface of water through Magritte's(Rene Magritte, 1898~1967) surrealistic works. In other words, Magritte's art secures a core dimension of human nature through a mysterious gap of conscious and settled space. Magritte's drawings often evokes strange and unsettling feelings in people who view his paintings. This is because routine objects are found in "unsuitable" places from which we usually find them in our everyday lives. "Reality" in Magritte's paintings makes it aware that it is a strained field of concealment and disclosure basically between truths, and we can learn that his behavior to overturn to paint in-visible things is finally an effort to restore the "real subject" to the viewer's reality. In other words, such reversion arouses a nostalgic desire for the objects existing in their original appearance as they are - natural condition that our gaze had not been distorted yet by anamorphic stains. - and the state when we are conscious of them normally. Such desire offers an opportunity for us to get out of mental depression rather than operates to us as an abnormal crack. It's a successive process of effort to search for lost subject and Paradise Lost facing up to reality of subject human that is to be a subject of world and life are ousted from their place by structure and authority of culture.

• Journal of Korean Society of Forest Science
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• v.76 no.4
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• pp.357-360
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• 1987

1. The hair cells on adaxial surface turned out to be penetration way of Gleosporium Thea sinensis in tea plant. 2. The most parts of Gleosporium Thea sinensis generated in tea plant were young leaves with first-fifth leaves from tip of shoot. 3. The proper temperature for spore germination on leaf is $25-27^{\circ}C$, soaked by water for 12 hours. 4. For prevention of Gleosporium Thea sinensis the drug-spay in tea plant would be the most effective when sprayed at this temperature range, and the control of Gleosporium Thea sinensis would be possible through selection of tea plant with few hairs. 5. The treatment of bordeaux mixture to prevent growth of conidiospore was 48.3% more effective than in control plot which were not sprayed. 6. The effect of sprayed bordeaux mixture decreased to about 28.5% after one week of spray.

• Journal of Ocean Engineering and Technology
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• v.30 no.4
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• pp.327-333
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• 2016

Reinforced concrete structures have found wide usage in land and maritime applications. However, the corrosion of reinforced concrete has been recognized as a serious problem from economic and safety standpoints. In previous studies, the corrosion behavior of the inner steel bar embedded in mortar (W/C: 0.4, 0.5) was investigated using electrochemical methods. In this study, multiple mortar test specimens (W/C: 0.6) with six different cover thicknesses were prepared and immersed in flowing seawater for five years. Subsequently, equations related to the cover thickness, period of immersion, and corrosion characteristics of the embedded steel bar were evaluated using electrochemical methods. Prior to immersion, the corrosion potentials indicated an increase with increasing cover thickness, and after five years, all corrosion potentials demonstrated a trend in the positive direction irrespective of the cover thickness. However, the relationships between the corrosion potential and cover thickness were not in complete agreement. Furthermore, after five years, all of the corrosion potentials indicated values that were nobler compared to those obtained prior to immersion, and their corrosion current densities also decreased compared to their values obtained prior to immersion. It was considered that the embedded steel bar was easily corroded because of the aggression of water, dissolved oxygen, and chloride ions; a higher W/C ratio also assisted the corrosion process. The corrosive products deposited on the surface of the steel bar for five years cast a resistance polarizing effect shifting the corrosion potential in the nobler direction. Consequently, it was considered that the W/C ratio of 0.6 showed nearly same results as those of W/C of 0.4 and 0.5. Therefore, the corrosion potential as well as various parameters such as the cover thickness, period of immersion, and W/C ratio must be considered at once for a more accurate evaluation of the corrosion property of reinforced steel exposed to marine environment for a long period.

• Korean Journal of Dental Materials
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• v.45 no.4
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• pp.301-310
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• 2018

The purpose of this study is to evaluate the compatibility of universal adhesives with two dual-cured resin cements. Eighty human molars were divided into eight groups. Tooth was embedded in self-curing acrylic resin and sectioned horizontally to exposure dentine surface. After polishing with 600-grit SiC paper, adhesives were applied. All-Bond Universal (Bisco), G-premio bond (GC), Scotch-bond universal (3M ESPE), Scotch-bond Multipurpose (3M ESPE) were used in this study. Calibra (Dentsply) as a conventional dual-curing resin cement and RelyX Ultimate (3M ESPE) as an amine free resin cement were used. The adhesives and the cements were applied according to the manufacturer's instructions. Final specimens were cylinder (diameter 2mm, height 3mm) shape. After storing in distilled water at $37^{\circ}C$ for 7 days the shear bond strength (SBS) test was performed. There was no significant difference in shear bond strength between the adhesives when RelyX Ultimate was used (p>0.05). However, when Calibra used with Scotch-bond Multipurpose and All-Bond Universal were used, statistically higher SBS was observed, as compared to the groups which Calibra cements with G-premio bond and Scotch-bond universal adhesive (p<0.05) were used. Within the limitations of this study, RelyX Ultimate resin cement was compatible with universal adhesives of various pH. All-Bond Universal adhesive was compatible with a resin cement containing the tertiary amine.

• Korean Journal of Remote Sensing
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• v.24 no.6
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• pp.535-549
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• 2008

Vicarious calibration for the satellite sensor relies on simulated TOA (Top-of-Atmosphere) radiances over various targets. In this study, TOA visible radiance was calculated over ocean targets which are located in five different regions over the Indian and Pacific ocean, and its possible use for the satellite sensor calibration was examined. TOA radiances are simulated with the 6S radiative transfer model for the comparison with MODIS/Terra and SeaWiFS measurements. Geometric angles and sensor characteristics of the reference satellites were taken into account for the simulation. AOT (Aerosol Optical Thickness) from MODIS/Terra, pigment concentrations from Sea WiFS, and ozone amount from OMI measurements were used as inputs to the model. Other atmospheric input parameters such as surface wind and total column water vapor were taken from NCEP/NCAR reanalysis data. The 5-day averaged radiances over all targets show that the percent differences between simulated and observed radiances are within about ${\pm}5%$ in year 2005, indicating that the calculated radiances are in good agreement with satellite measurements. It has also been shown that the algorithm can produce the SeaWiFS radiances within about ${\pm}5%$ uncertainty range. It has been suggested that the algorithm can be used as a tool for calibrating the VIS bands within about 5% uncertainty range.

• Korean Journal of Remote Sensing
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• v.23 no.4
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• pp.311-321
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• 2007

The diffuse attenuation coefficient for down-welling irradiance $K_d({\lambda})$, which is the propagation of down-welling irradiance at wavelength ${\lambda}$ from surface to a depth (z) in the ocean, and underwater visibility are important optical parameters for ocean studies. There have been several studies on $K_d({\lambda})$ and underwater visibility around the world, but only a few studies have focused on these properties in the Korean sea. Therefore, in the present study, we studied $K_d({\lambda})$ and underwater visibility around the coastal area of the Yellow Sea, and developed $K_d({\lambda})$ and underwater visibility algorithms for ocean color satellite sensor. For this research we conducted a field campaign around the Yellow Sea from $19{\sim}22$ September, 2006 and there we obtained a set of ocean optical and environmental data. From these datasets the $K_d({\lambda})$ and underwater visibility algorithms were empirically derived and compared with the existing NASA SeaWiFS $K_d({\lambda})$ algorithm and NRL (Naval Research Laboratory) underwater visibility algorithm. Such comparisons over a turbid area showed small difference in the $K_d({\lambda})$ algorithm and constants of our result for underwater visibility algorithm showed slightly higher values.

• Korean Journal of Remote Sensing
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• v.22 no.4
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• pp.243-253
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• 2006

As the ocean and beaches have suffered from the losses of sand, it is necessary to monitor the zones that are prone to erosion continuously with the object of the long-term management. However, each ward offices are busy trying to supply sand without analyzing the marine and beach topographic changes. Therefore a long term effect of erosion has not been shown. In this study, we proposed methods to collect accurate spatial data of the oceans and beaches through sounding and GPS surveys, and detected and analyzed topographic changes quantitatively and qualitatively, by using an integrated RS and GIS techniques. The result of this study revealed that the marine topography has been eroded for 25 years, because of the straight construction of the river and the vast development of urban features, in addition with change of the mean depth 0.40 m, the water surface area 11,028 $m^2$, and submarine volume 2,207,884 $m^3$. The beach topography has accreted for 5 years and the change of the mean elevation is 0.27m, the area 6,501 $m^2$, and volume 25,667 $m^3$, because of the installation of geogrids and the seasonal effect. We conducted monitoring works on the topographic survey of the ocean and beaches and analyzed the present condition of the coastal erosions. Therefore, it is estimated that necessary information on the supply of sand, the safe marine leisure and the management of bating place could be provided.

• Korean Journal of Remote Sensing
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• v.26 no.2
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• pp.115-122
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• 2010

In this study, we analyzed ridge-runnel structure and ripple marks by using Envisat ASAR, JERS-1 SAR images and in-situ data in Mongsanpo intertidal flat located in Taean-Gun, Korea. A group of light-and-dark lines parallel to the shoreline, alternating 3-5 times, were observed in the intertidal flat in Envisat ASAR images. The patterns are related to ridge-runnel structure in the intertidal flat exposed to air. Well-drained runnels, typically with ripple marks, showed strong backscattering while runnels submerged by surface water or ridges, typically smooth with no ripple, have weak backscattering coefficients in Envisat ASAR images. In JERS-1 SAR images, however, the backscattering was very low on the entire intertidal flat and no ridge-runnel structure could be observed. The wavelengths of ripple marks measured from in-situ observations have ranges from 4 to 10 cm that satisfies the Bragg scattering condition of the 1st-order in Envisat ASAR images operating in C-band, but not in JERS-1 SAR that used L-band. Through this study using SAR images, we could successfully analyze the sedimentary conditions of intertidal flats with ridge-runnel and ripple marks which are not easily observed by optical sensors. It is expected that the results of this study with SAR images will contribute to the sedimentary research over intertidal flats.

• Korean Journal of Remote Sensing
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• v.14 no.1
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• pp.37-52
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• 1998

The NSCAT(NASA Scatterometer) carried by the japanese Advanced Earth Observing Satellite(ADEOS) was the first high resolution(25 km) device for the direct wind measurement over the ocean. Even it was ceased to operate in lune of 1977 because of the power failure, it gave the first opportunity to the marine meteorologists to study the direct measured ocean wind during its 9 months of operation, especially around Korea. This study is to show monthly mean ocean wind and wind stress curl fields around Korea from January, 1997 to June, 1997. Mean ocean winds in January are predominantly northwesterly and the strongest wind(12 m/s) is found near Vladivostok. The winds in the western East Sea are strongly inf1uenced by the mountain range in Korea and these topographically influenced winds make about five times larger wind stress curl fields than previous estimates based on the weather maps. The calculation of Sverdrup transport in the East Sea shows the possibility of the directional change of the East Korean Cold Current from southward to northward direction caused by the winter wind. The downwelling area near North Korea has maximum estimated speed of 45 m in january and this wind induced downwelling makes good condition for the formation of Intermediate East Sea Water together with vigorous mixing by the strong wind.