• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.5
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• pp.425-431
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• 2006

In order to investigate the effects of ethylene on the seed development of three corn types (dent, sweet, and super sweet corns), aminoethoxyvinyl glycine (AVG) and silver thiosulfate (STS) and ethephon (2-chloroethylphosphonic acid, CEPA) were applied either on whole plants or shanks of ears at 9 and 21 days after silking. Ethylene production of developing super sweet corn seeds was much higher than those of sweet and dent corns. The cavity in the endosperm tissues of the super sweet corn started earlier and endosperm was collapsed more severely compared to those of sweet and dent corns. Ethylene production seemed to be related to the death of endosperm cells to form a cavity. Application of AVG and STS reduced ethylene production and delayed cavity formation in endosperm of super sweet corn seeds, while CEPA increased ethylene production and enhanced the time of cavity formation. AVG and STS increased 100-seed weight, while CEPA decreased.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.529-539
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• 2010

In order to evaluate the effect of soil salinity and culturing conditions including compost application and vinyl mulching on the maintenance of ridge and the growth of upland crops, three crops such as corn, soybean and sweet potato were experimented by using three or four cultivars of crops in the Saemangeum reclaimed tidal land. Average soil salinity before seeding was 2 dS $m^{-1}$, which was low enough for general upland crops to grow. However, high soil EC more than 16 dS $m^{-1}$ was observed in some parts of the experimented field. In the experiment, it was concluded that growth retardation and yield reduction of summer upland crops might be from severe erosion of ridge, soil compaction, flooding or wet soil condition and high salinity of some parts, and then these deteriorations were possibly improved for good crop growth and yield increase by compost application and vinyl mulching cultivation in the Saemangeum reclaimed tidal land.

• Journal of Conservation Science
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• v.19
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• pp.5-18
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• 2006

The Mireuksaji stone pagoda of the Iksan was built in Muwang King of Baekjae Kingdom and has maintained its present status through several rebuilding process. Recently, the structural unbalance of the pagoda has worsened, so for scientific maintenance recovery of its original pagoda form, the pagoda is under dismantling process. The original form of this pagoda is being presumed to be a plane square pagoda of nine stories, though only a portion of six stories remains until today. The destroyed part from collapse was liked in insecure pagoda form by Japanese in year of 1915. On the surface of the stone which has gone through the present time, efflorescence appeared as precipitation substance over crusted and due to this phenomenon, the structure and color of thee original stone haven't been preserved. Therefore, quantitative analysis on its kind, emitted status and contamination type of secondary inorganic contamination substance of the over crusted surface were analyzed. Also through reaction experiments, contamination type was defined and tests have been applied to find the requirements that will wash out the contaminants. The result of this study will provide the base of quantitative analysis on the kind of inorganic contamination of the surface of stone assets, and it shall also contribute to the application of scientific maintenance recovery of surface cleaner for efflorescence.

• The Journal of Engineering Geology
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• v.15 no.2 s.42
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• pp.133-144
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• 2005

Stability investigations were conducted for the heap of coal associated wastes occurred from D mine located in Gang-Won Province from the geotechnical and environmental engineering aspect, and a countermeasure was also examined to increase the stability in this area. Quality of water flowed from the heap of coal associated wastes was identified as Am. Slope stability investigations were conducted with both circular failure analyses using SLOPILE program and planar failure analyses in cases of dry, rainy, and ordinary slopes. The results of circular failure analyses indicated that the factor of safety is 0.78 for rainy case. for planar failure analyses, the factor of safety decreases with increase the depth and reaches below 1 about 4m depth for rainy case. A retaining wall system with backfill using the recycled-concrete aggregates as a practical scheme was suggested to satisfy both demands: reducing Am generation, and enhancing slope stability in the deposits of coal associated wastes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.3
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• pp.165-170
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• 1981

Recently an unknown microbial desease and some parasitic crustaceans are prevailing in the sea-weed farms of Uudaria pinnatifida along the south-eastern coast of Korea.(1) Green spots probably caused by the microbial pathogens were found on the fronds of Undaira Pinnatifide. Particularly they were densely distributed on the distal half of the fronds. The tissues of the green spot area rot off, and small holes with green colored margin are formed. The holes at the distal part of the fronds are enlarged and they finally coalesced each other. Then this process accelerates decaying of the distal ends of the fronds.. The fronds growing in the central part of the farms are usually severely damaged, whereas in the marginal area of the farm toward the open sea side the damage is less serious. An examination revealed that the deseased fronds bore a number of viable bacteria, $6.8\times10^5\;to\;1.2\times10^6$ per gram at $15^{\circ}C$, whereas the healthy fronds $1.1\times10^4$. Twenty-six kinds of colonies, 247 strains of bacteria, were isolated from deseased fronds, belonging to Moraxella, Achromobacter, Vibrio, Flavobacterium, Acinetobacter, Pseudomonas, etc. (2) Pinholes occurred in one series on the frond. They were probably caused by a harpacticoid copepod, Thalestris sp. Seven years ago when the disease was first found to occur the copepod was observed on the fronds from March of the year. Recently, however, they have been found as early as December of the previous year. (3) A gammarid amphipod, Ceinina iaponica, invades the pith of the midrib through holdfast of thalli. This rarely causes the longitudinal seperation of the entire frond through the midrib as they bore a tunnel in the pith. Sometimes holdfasts of tile heavy damaged thalli make the frond departed from the substrate.

• The Korean Journal of Malacology
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• v.27 no.3
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• pp.181-190
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• 2011

This study was investigated to find out the change of reproductive and histological biomarkers of Ruditapes philippinarum exposed to nonylphenol (NP). Experimental period was 16 weeks. Experimental groups were composed of one control condition and three NP exposure conditions (0.05, 0.1, $0.2 mg\;NP\;L^{-1}$). Gonad index was higher in exposure group than control in female and higher in control than exposure group in male. Intersexuality in the NP exposure group was 14.56% with male exhibiting higher ratio than female. Histological analysis of organ system illustrated expansion of hemolymph sinus, loss of striated border of inner epidermis and degeneration of mucous cell in the mantle. In the gill partially disappearance of frontal and lateral cilia, degeneration of mucous cell were observed. Also, hyperplasia of epithelium and disappearance of striated border were observed in the foot. As the concentration of NP increased, the accumulation of lipofuscin increased in the digestive gland. The results of this study suggest that NP induces reduction of survival rate, histopathology and intersex of R. philippinarum. Furthermore, it is indentified that NP functions as an estrogenic effector on the reproduction of R. philippinarum.

• Geotechnical Engineering
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• v.14 no.6
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• pp.17-32
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• 1998

The Bakun hydroelectric project includes the construction of a hydroelectric power plant with an installed capacity of 2,520MW and a power transmission system connecting to the existing transmission networks in Sarawak and Western Malaysia, The power station will consist of a 210m height concrete faced rockfill dam. During the construction of the dam and the power facilities the Balui river has to be diverted by three diversion tunnels with a length of some 1,400m each. The inner diameter of the tunnels is 12m and the tunnel width is 16m at the portal area. This paper describes the stability analysis and design methods for the open cut rock slopes in the inlet and outlet area of the diversion tunnels. The geotechnical parameters employed in stability calculations were given as a function of four. defined Rock Mass Types (RMT) which were based on RMR system from Bieniawski. The stability calculations procedure of the rock slopes are divided into two stages. In the first stage, it is calculated for the stability of each 'global' slope without any rock support and shotcrete system. In the second stage, it is calculated for each 'local'slope stability with berms and supported with rock bolts and shotcrete. The monitoring instrumentation was performed continuously and some of the design modification was carried out in order to increase the safety of failed area based on the unforeseen geological risks during the open cut excavation.

• Korean journal of communication and information
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• v.77
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• pp.73-107
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• 2016

The general programming channels, newly introduced around the beginning of the 2010s, have grown into powerful journalistic agencies, the far-reaching social influences of which are not confined by the economic effects within the South Korean media industry. They are now rendered to become part of major socio-political institutions that try to secure their privileges based on broadcast journalism, and to widen their business opportunities through those special kind of social practices. This research has taken a path of theoretical endeavour to devise a conceptual framework that will effectively lead to a series of academic investigation into the socio-political characteristics of general programming channels. To this end, specific attention is paid to such theoretical and conceptual resources as the instrumentalization of media by the politics, the political sociology of media power, media-political parallelism, and the structural coupling between the political and the media systems. This paper suggests that general programming channels have emerged as a new interface that accommodates and actualizes the structural coupling between the two societal subsystems, and in the course of that, they undercut the vulnerable basis of media public sphere, effectively replacing it with entertaining media-political sphere constructed and managed by themselves. This sphere is where the media system's logic and the poltical system's logic are intertwined, simutaneously accelerating not only the mediatization of the politics but also the politicization of the media.

• Journal of Hydrogen and New Energy
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• v.18 no.3
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• pp.230-237
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• 2007

Titania nanotube(TiNT) and CdS sol were synthesized by hydrothermal reaction under strongly basic condition and by precipitation reaction of $Cd(N0_3)_2$ and $Na_2S$ aqueous solutions, respectively. After preparing a series of CdS-TiNT composite films on $F:SnO_2$ conducting glass with variation of the mole ratio (r) of TiNT/(CdS+TiNT), their visible light absorption, photocatalytic activities for hydrogen production, and the photocurrent generation were examined. In general, this CdS-TiNT series showed lower photocatalytic activities and photocurrent generation under Xe light irradiation compared to their counterparts, i.e., CdS-$TiO_2$ particulate series. It appeared that TiNTs are not so effective photocatalyic material in spite of their larger specific surface areas compared to $TiO_2$ nanoparticles, because they indicate a poor crystallinity and less intimate interaction or contact with CdS particles owing to the tubular morphology and an easy agglomeration among themselves.

• Journal of the Korea Concrete Institute
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• v.15 no.6
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• pp.848-855
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• 2003

During concrete placement, the partially distributed load due to the concrete placement paths creates the lateral force in the connection parts of the shore. In order to restrain this lateral force, the nails must be used in the upper and lower connection parts of shores. But, for the convenience of the construction and dismantling of the shores, the workers hardly use the nails. In this case, the connections of shore cannot resist the shear force and rotation. And this situation may cause the collapse of form-shore system. Therefore, contact and spring models for the connection analysis of the form-shore systems are required. If we take into account this construction situation, we need to understand the effects of shear and rotation stiffness according to the several types of connection parts in shores as a case study. This study evaluates the shear and rotation stiffness of the connection parts of shores according to the variations of the lengths, numbers and positions of nails, and then presents the experimental results depending on the end conditions of shores. And, these results can be used as a spring model and critical load evaluation data for the connection analysis of form-shore system.