• Korean journal of applied entomology
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• v.25 no.2 s.67
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• pp.63-70
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• 1986

Severity of incidence of white rot on apple fruit ranged from 5 to 16% and averaged 9% over major apple growing area in 1981. An isolate of Botryosphaeria ribis obtained from rotted apples developed lesions on leaves, branches and fruits of apple, pear, peach and grape in a series of wound inoculation test. B. ribis grew well on both potato sucrose agar and oatmeal agar. The best condition for vegetative growth on these two media was at $25{\sim}30^{\circ}C$ pH 4 and $10{\sim}15%$ sucrose content under light illumination. Rot development on fruit was first observed in the orchard at early August when sugar content in fruit reached 9.0%. Thereafter, number of rotted apples increased as sugar content increased. There was no correlation between the pH of juice of fruit and rot incidence. Infection on fruit began to occur as early as mid-June when young fruits were formed and infections were continued until harvest. When apple fruits were collected at 10-day intervals from the orchard beginning from early June and were wound-inoculated with B. ribis, rot lesion developed regardless of the stage of fruit growth. Incidence of white rot in the orchard was severe on Golden-delicious and Yukou, intermediate on Aoli, Fugi and Indo, and least on Jonathan and Red-delicious.

• Journal of the Korean Geotechnical Society
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• v.28 no.6
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• pp.19-29
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• 2012

Pack micropiles were recently developed to improve pile capacity of general micropiles. Pack micropiles were made by warping thread bar or steel pipe of general micropile by geotexlile pack and grouting inside the pack with pressure. According to the pressure, the boring hole could be enlarged. A series of pile uplift tests were performed on three micropiles. Two out of the three piles were the pack micropiles and the other was the general micropile, in which a thread bar was used in the boring hole. According to the pressure applied to the pack micropiles, the diameter of boring hole was enlarged from 152 mm to 220 mm. Unit skin friction mobilized on side surfaces of micropiles increased with displacement of pile head and reached on a constant value, which represents that the relative displacement between piles (or thread bar) and soils was reached on critical state. And the uplift resistance of pack micropile was higher than that of general micropile. Two reasons can be considered: One is that the frictional surface increases due to enlarging diameter of boring holes and the other is that the unit skin friction could increase due to compressing effect of surrounding soils by soil displacement as much as the enlarging volume of boring hole. The compression effect appeared at deeper layer rather than surface layer. The unit skin friction mobilized on micropiles with small diameter was higher than the ones on large bored piles.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.1-11
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• 1991

A hull form for an Aframax tanker whore form parameters cover the values of $C_B{\simeq}0.8,\;L/B{\simeq}5.5\;and\;B/d{\simeq}3.5$ has been developed by applying a composite stern frameline concept and its excellent performance has been evaluated through a series of model tests at the Korea Research Institute of Ships and Ocean Engineering. The tests showed that this concept was very much promising in the cases of wide breadth and shallow draught vessels and suitably applicable to the stern frameline shape. For the comparison, a hull form developed by Japanese 'H' yard has been selected and the performances of two hull forms were evaluated by model tests and theoretical calculations. The comparison shows that Daewoo hull form requires less effective power by 10% and less delevered power by 5-6% at both full load and ballast conditions. In addition, it is suggested that Hushes method can give better correlationthan Froude method because the full scale resistance extrapolated by Froude method would be very much optimistic in case of the hull form with very low value of form factor.

• Solar Energy
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• v.17 no.4
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• pp.3-11
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• 1997

Because grain boundaries in polycrystalline silicon act as potential barriers and recombination centers for the photo-generated charge carriers, these defects degrade conversion effiency of solar cell. To reduce these effects of grain boundaries, we investigated various influencing factors such as thermal treatment, various grid pattern, selective wet etching for grain boundaries, buried contact metallization along grain boundaries, grid on metallic thin film. Pretreatment above $900^{\circ}C$ in $N_2$ atmosphere, gettering by $POCl_3$ and Al treatment for back surface field contributed to obtain a high quality poly-Si. To prevent carrier losses at the grain boundaries, we carried out surface treatment using Schimmel etchant. This etchant delineated grain boundaries of $10{\mu}m$ depth as well as surface texturing effect. A metal AI diffusion into grain boundaries on rear side reduced back surface recombination effects at grain boundaries. A combination of fine grid with finger spacing of 0.4mm and buried electrode along grain boundaries improved short circuit current density of solar cell. A ultra-thin Chromium layer of 20nm with transmittance of 80% reduced series resistance. This paper focused on the grain boundary effect for terrestrial applications of solar cells with low cost, large area, and high efficiency.

• Molecules and Cells
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• v.40 no.8
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• pp.567-576
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• 2017

The $Na^+/H^+$ exchanger is responsible for maintaining the acidic tumor microenvironment through its promotion of the reabsorption of extracellular $Na^+$ and the extrusion of intracellular $H^+$. The resultant increase in the extracellular acidity contributes to the chemoresistance of malignant tumors. In this study, the chemosensitizing effects of cariporide, a potent $Na^+/H^+-exchange$ inhibitor, were evaluated in human malignant mesothelioma H-2452 cells preadapted with lactic acid. A higher basal level of phosphorylated (p)-AKT protein was found in the acid-tolerable H-2452AcT cells compared with their parental acid-sensitive H-2452 cells. When introduced in H-2452AcT cells with a concentration that shows only a slight toxicity in H-2452 cells, cariporide exhibited growth-suppressive and apoptosis-promoting activities, as demonstrated by an increase in the cells with pyknotic and fragmented nuclei, annexin V-PE(+) staining, a $sub-G_0/G_1$ peak, and a $G_2/M$ phase-transition delay in the cell cycle. Preceding these changes, a cariporide-induced p-AKT down-regulation, a p53 up-regulation, an ROS accumulation, and the depolarization of the mitochondrial-membrane potential were observed. A pretreatment with the phosphatidylinositol-3-kinase (PI3K) inhibitor LY294002 markedly augmented the DNA damage caused by the cariporide, as indicated by a much greater extent of comet tails and a tail moment with increased levels of the p-histone H2A.X, $p-ATM^{Ser1981}$, $p-ATR^{Ser428}$, $p-CHK1^{Ser345}$, and $p-CHK2^{Thr68}$, as well as a series of pro-apoptotic events. The data suggest that an inhibition of the PI3K/AKT signaling is necessary to enhance the cytotoxicity toward the acidtolerable H-2452AcT cells, and it underlines the significance of proton-pump targeting as a potential therapeutic strategy to overcome the acidic-microenvironment-associated chemotherapeutic resistance.

• Journal of the Korean Geotechnical Society
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• v.28 no.9
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• pp.57-67
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• 2012

In the design for piled rafts, the load capacity of the raft is in general ignored and the load capacities of pile are only considered for the estimation of the total load carrying capacity of the piled raft. The axial resistance of piled raft is offered by the raft and group piles acting on the same supporting ground soils. As a consequence, pile - soil - raft and pile - soil interactions, occurring by stress and displacement duplication with pile and raft loading conditions, acts as a key element in the design for piled rafts. In this study, a series of centrifuge model tests has been performed to compare the axial behavior of group pile and raft with that of a piled raft (having 16 component piles with an array of $4{\times}4$) at the stiff and soft clays. From the test results, it is observed that the interactions of piles, soil, and raft has little influences on the load capacities of piles and raft in piled rafts compared with the load capacities of group piles and raft at the same clay soil condition.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.25 no.1
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• pp.6-11
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• 1989

Some distinctive defects in the conventional stow net were examined and presented in the previous report of this series. To find out the more effective gear by correcting the defects, the authors carried out another experiment by using a newly designed gear. 1. Special features of the newly designed gear are: (1) stretched width of front end on top, bottom and side panel are decreased 20%, on the other hand, the frank of the panels are increased 10% compared with the conventional gear. Front end of top and bottom panels are bias cutten up to 20% of the length of panels. (2) Length of the head rope and ground rope are shortened 6% by changing of the shape of the top and bottom panels. (3) Lacing lines are attached to four longitudinal seaming lines with suitable hanging ratio. (4) Stretched height of the shearing device were shortened 17%, and the buoyancy on top of the device were increased 20%. (5) Length of the biforked pendants were arranged to be shorter on top-most and bottom-most ones, and loner on middle ones. 2. The observed result can be expressed as (1) Wrinkles in the front end of top panels are removed and fringe line of panels become smooth. (2) Opening height of mouth is observed 3% higher than that of the conventional gear. (3) Opening width is 1.5 to 1.6 times wider than that of the conventional gear. (4) Hydrodynamic resistance is decreased 10%-17%.

• Journal of Korea Water Resources Association
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• v.54 no.12
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• pp.1205-1214
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• 2021

Precipitation is one of a major causes of landslides by rising of pore water pressure, which leads to fluctuations of soil strength and stress. For this reason, precipitation is the most frequently used to determine the landslide thresholds. However, using only precipitation has limitations in predicting and estimating slope stability quantitatively for reducing false alarm events. On the other hand, Soil Moisture (SM) has been used for calculating slope stability in many studies since it is directly related to pore water pressure than precipitation. Therefore, this study attempted to evaluate the appropriateness of applying soil moisture in determining the landslide threshold. First, the reactivity of soil saturation level to precipitation was identified through time-series analysis. The precipitation threshold was calculated using daily precipitation (P_daily) and the Antecedent Precipitation Index (API), and the hydrological threshold was calculated using daily precipitation and soil saturation level. Using a contingency table, these two thresholds were assessed qualitatively. In results, compared to P_daily only threshold, Goesan showed an improvement of 75% (P_daily + API) and 42% (P_daily + SM) and Changsu showed an improvement of 33% (P_daily + API) and 44% (P_daily + SM), respectively. Both API and SM effectively enhanced the Critical Success Index (CSI) and reduced the False Alarm Rate (FAR). In the future, studies such as calculating rainfall intensity required to cause/trigger landslides through soil saturation level or estimating rainfall resistance according to the soil saturation level are expected to contribute to improving landslide prediction accuracy.

• Cross-Cultural Studies
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• v.42
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• pp.131-163
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• 2016

The issue of migrants has always been a social problem in France. Particularly, migration issues from the Maghreb region to multicultural France are recognized as topics of confrontation and conflict. One of the many reasons would be that the Maghreb migrant issue is interpreted with a hostile or conflicting 'Arab-Islam' meaning in the West. Therefore, the naming of natives from this region as 'Arab-Maghrebis' has become a common phenomenon. However, deeper understanding of the Maghreb region will explain that such naming could produce a number of problems. This is because the native Maghrebis, not only in the Maghreb region but also in France, are Berbers. Among the various Berbers, the Kabyles are in many ways different from the Arabs in their language, culture, and way of thinking. Apart from the difference in their lifestyle, there is a deep anti-Arab sentiment within them that represents their resistance against the hundreds-of-years Arab domination. This feature has also been used as France's tool of colonial division policy during the colonization period. The purpose of this study is to discuss the settlement process of the Kabyles in France by paying attention to their features. The Kabyles were the first to migrate to France among the natives of the Maghreb region. This study focuses on the process of their migration and search for identity, as well as how they continued to form community and the Berber's cultural movement. Through these series of processes, it is possible to point out the fictitious claim in France and in Korea that Maghrebis are Arab-Muslims. Lastly, the current use of Berber language in France and Algeria is not a coincidental phenomenon, rather it has a connection with the prolonged cultural movement and the settlement process of the migrants in France.

• Journal of Life Science
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• v.31 no.8
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• pp.745-754
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• 2021

Deterioration of the immune function weakens the body's resistance to various infections, leading to a series of diseases. Immunomodulatory biomaterials have been used to reduce the side effects of immunosuppressants or to enhance immunity. Agarwood is the aromatic resinous portion of Aquilaria trees that has been traditionally used as a medicinal herb for the treatment of various diseases. Although previous studies have shown that agarwood can improve the body's immunity, evidence for this claim is still lacking. In this study, the immune-enhancing effects of the agarwood methanol extracts of Aquilaria malaccensis Lamk were evaluated in a RAW 264.7 macrophage model. Based on the results, the agarwood extracts markedly enhanced phagocytosis in the absence of cytotoxicity. The agarwood extract-treated RAW 264.7 cells exhibited the typical morphology of activated macrophages, which are spindle-shaped with elongated filopodia. Agarwood extract also significantly increased the production of nitric oxide (NO), which is associated with the increased expression of inducible NO synthase. Moreover, the secretion and expression levels of cytokines, such as tumor necrosis factor-α and interleukin (IL)-1β and IL-6, were increased by agarwood treatment. Notably, these are also associated with a mitogen-activated protein kinase signaling pathway. Taken together, our findings provide scientific evidence that agarwood has potential immune-enhancing effects in vitro.