• Korean Journal of Remote Sensing
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• v.33 no.5_3
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• pp.855-866
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• 2017

Several research cases using remote sensing methods to analyze changes of storage and dynamics of groundwater aquifer were reviewed in this paper. The status of groundwater storage, in an area with regional scale, could be qualitatively inferred from geological feature, surface water altimetry and topography, distribution of vegetation, and difference between precipitation and evapotranspiration. These qualitative indicators could be measured by geological lineament analysis, airborne magnetic survey, DEM analysis, LAI and NDVI calculation, and surface energy balance modeling. It is certain that GRACE and InSAR have received remarkable attentions as direct utilization from satellite data for quantification of groundwater storage and dynamics. GRACE, composed of twin satellites having acceleration sensors, could detect global or regional microgravity changes and transform them into mass changes of water on surface and inside of the Earth. Numerous studies in terms of groundwater storage using GRACE sensor data were performed with several merits such that (1) there is no requirement of sensor data, (2) auxiliary data for quantification of groundwater can be entirely obtained from another satellite sensors, and (3) algorithms for processing measured data have continuously progressed from designated data management center. The limitations of GRACE for groundwater storage measurement could be defined as follows: (1) In an area with small scale, mass change quantification of groundwater might be inaccurate due to detection limit of the acceleration sensor, and (2) the results would be overestimated in case of combination between sensor and field survey data. InSAR can quantify the dynamic characteristics of aquifer by measuring vertical micro displacement, using linear proportional relation between groundwater head and vertical surface movement. However, InSAR data might now constrain their application to arid or semi-arid area whose land cover appear to be simple, and are hard to apply to the area with the anticipation of loss of coherence with surface. Development of GRACE and InSAR sensor data preprocessing algorithms optimized to topography, geology, and natural conditions of Korea should be prioritized to regionally quantify the mass change and dynamics of the groundwater resources of Korea.

• Radiation Oncology Journal
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• v.19 no.1
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• pp.16-20
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• 2001

Purpose : To evaluate the effectiveness and tolerance of the postoperative radiation therapy for patients with Stage III thymoma and to define the optimal radiotherapeutic regimen Materials and Methods : We retrospectively analyzed the records of 24 patients with Stage III thymoma who were referred for postoperative radiation therapy in our institution from June, 1987 to May, 1999. Surgical therapy consisted of total resection in one patient, subtotal resection in seventeen, and biopsy alone in six patients. Age of the patients was ranged from 20 to 62 years with mean age of 47 years. Male to female ratio was 14 to 10. Radiation therapy was delivered with linear accelerator producing either 6 MeV or 10 MeV photons. The irradiated volume included anterior mediastinum and known residual disease. The supraclavicular fossae were not irradiated. The delivered total dose was ranged from 30 to 56 Gy. One patient received 30 Gy and eighteen patients received minimum of 50 Gy. Follow up period was ranged from 12 months to 8 years with median follow up of 40 months. Results : The overall local control rate for entire group of patients was $67\%$ at 5 years. The cumulative local failure rates at one, three and five year were $18\%,\;28\%\;and\;33\%$, respectively. In patients treated with subtotal resection and biopsy alone, local control rate was $76\%\;and\;33\%$, respectively. The actuarial observed survival rate at 5 years was $57\%$, and actuarial adjusted survival at 5 years was $72\%$. The difference between 5 year survival rates for patients treated with subtotal resection and biopsy alone was not statistically significant $(62\%\;vs\;30\%)$. Conclusion : We might conclude that postoperative radiation therapy was safe and effective treatment for patients with Stage III thymoma. Postoperative radiation therapy is recommended in cases where tumor margin is close or incomplete resection is accomplished.

• Korean Journal of Weed Science
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• v.10 no.2
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• pp.114-121
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• 1990

Inactivation in soil absorption, translocation of 2, 4-D by plants vary depending upon soil environments and herbicide formulations. Experiment was conducted in a glasshouse using rectangular pots($1350cm^2$) to evaluate the growth responses of barnyardgrass (Echinochloa crus-galli) and Indian jointvetch (Aesehyrcomene indica) to two formulations of 2, 4-D. The formulations used were 40% 2, 4-D amin salt (2, 4-D/AS) and 19.7% complex of rice husk lignin and 2, 4-D (2, 4-D/LG) which were applied at 200g ai/ha. Soil environments included fertilizer levels, soil pH, organic matter contents, and soil textures, Each treatment was replicated three times. The herbicidal activity of 2.4-D increased and lasted with increased levels of fertilizer. The activity also increased and lasted with low soil pH and decreased content of organic matter. Generally 2, 4-D/LG showed higher and longer herbicidal activity than 2. 4-D/AS for both test plants under all conditions applied. However, the herbicidal activity was influenced by the formulations more than by soil textures. It was thought that 2, 4-D/AS was released in a short time and inactivated readily while 2, 4-D/LG was slowly released and gave an opportunity of absorption by plants for a long period.

• Korean Journal of Weed Science
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• v.1 no.1
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• pp.30-43
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• 1981

On unwedded paddy fields, six cropping patterns of rice cultivation, namely direct broadcast seeding, direct row seeding, machine transplanting, early season hand transplanting, standard season hand transplanting, and late season hand transplanting, were detected with two representative rice cultivars (Milyang 23 and Sadominori) to estimate the comparative fluctuation patterns of weed flora. As a result, number of emerged weed species, most crowding stages, differences of weed growth among cropping patterns, possible tendencies of competition in plant heights among plant groups, variations in Importance Values, and Simpson's Index analysis were discussed, respectively.

• Korean Journal of Weed Science
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• v.31 no.3
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• pp.279-288
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• 2011

To suggest the weed management technique for environment friendly rice cultivation, we investigated occurrence patterns of weeds, the actual condition of weed management, and rice yield at the environment friendly agricultural complex located in Honam and Chungnam regions. The practical performance of weed management was relatively satisfactory in decreasing order of agricultural technique with golden-apple-snail (GAS) > agricultural technique with duck (Duck) > agricultural technique with rice bran (RB) > agricultural technique with soft-shelled turtle (ST). In the rice fields employed by agricultural technique with GAS, the dominant weeds were Echinochloa crus-galli, Ludwigia prostrata, Monochoria vaginalis, Sagittaria trifolia, and Aneilema keisak. However, E. crus-galli, M. vaginalis, L. prostrata, Aeschynomene indica and Bidens frondosa were found as dominant weeds at the fields using the Duck and E. crus-galli, M. vaginalis, L. prostrata, Polyganum hydropiper and Eleocharis kuroguwai at the fields using RB. In comparison of rice yield ($5.2\;MT\;ha^{-1}$) obtained from the conventional cultivation using herbicides, about 93% was reached by Duck, about 91% by GAS, about 92% by RB, and about 78% by ST. When rice qualities obtained from environment friendly rice cultivation were compared with those from the conventional cultivation, the producing rates of perfect kernel, immature kernel, immature opaque kernel, cracked rice, and damaged kernel were lower in the former cultivation, whereas contents of protein, amylose, and fatty acid were similar in the two cultivation methods. The problems found in the environment friendly agriculture were poor plowing and harrowing, carless irrigation management, and geological poor condition as cultivation area with cold water. These have caused severe infestation of weeds, frequent incident of disease and insect pest, and rice lodging. This resulted in reduction of rice yield as high as about 32 to 79% as compared with the conventional cultivation using herbicides.

• The Korean Journal of Nuclear Medicine
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• v.33 no.1
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• pp.84-93
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• 1999

Purpose: We investigated the direct labeling method of antibody with $^{99m}Tc$ and $^{188}Re$ and examined the stability and function of these labeled compounds in in vitro and in vivo. Materials and Methods: Disulfide bond of nonspecific human IgG was reduced to -SH group by 2-mercaptoethanol. Stannous ion was used to reduce $^{99m}Tc$ and $^{188}Re$. The stability of $^{99m}Tc$-IgG and $^{188}Re$-IgG was estimated upto 24 hrs. Biodistribution was evaluated in abscess bearing rats at 4 and 24 hr post-injection of $^{99m}Tc$ or $^{188}Re$ labeled IgG. Results: The number of -SH group per reduced IgG molecule was 2.34. The labeling yield of $^{99m}Tc$-IgG and $^{188}Re$-IgG were 90% and 95%, respectively The stability of $^{99m}Tc$-IgG at 1, 4, 6 and 24 hr was 91%, 83%, 78%, 7% and that of $^{188}Re$-IgG at 1, 4, 16 and 24 hr was 94%, 80%, 47%, 42%, respectively. At 4 hr post-injection of $^{99m}Tc$-IgG, high uptake was found on kidney, blood, stomach and abscess ($9.42{\pm}0.68,\;1.43{\pm}0.24,\;0.86{\pm}0.18,\;0.72{\pm}0.10$ %ID/g, respectively). The uptakes at 24 hr were kidney, abscess,.itomach, and blood in descending order. In case of $^{188}Re$-lgG, high uptake at 4 hr post injection appeared on kidney, blood, abscess and stomach ($3.92{\pm}0.62,\;1.32{\pm}0.08,\;0.88{\pm}0.01,\;0.26{\pm}0.06$, respectively). The uptakes at 24 hr were kidney, abscess, blood and stomach in descending order. The abscess to blood uptake ratio of $^{99m}Tc$-IgG was 0.5 at 4 hr and 2.02 at 24 hr and that of $^{188}Re$-IgG was 0.67 and 1.29. Conclusion: $^{99m}Tc$-IgG and $^{188}Re$-IgG canbe labeled efficiently with direct labeling method. However, $^{99m}Tc$-IgG and $^{188}Re$-IgG, labeled with direct method, was unstable. Further study is needed to enhance the stability of the antibody labeling.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.937-942
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• 2004

Physicochemical properties and mineral composition of seaweed salts prepared by incineration and osmotic dehydration methods were determined. As the incineration temperature increased, yield of seaweed salts, insoluble solids, pH, alkalinity, and oxidation-reduction potential (ORP) decreased. Alkalinity of salt prepared with sea tangle was higher than that of sea mustard. ORP decreased by incineration above $700^{\circ}C$, and was lower in salt with sea tangle. As incineration temperature increased, amounts of K and Ca in seaweed salt increased, whereas that of Mg decreased. Potassium and Ca contents of seaweed salt increased remarkably compared with those of common salt. Potassium content of sea tangle salt was higher than that of sea mustard. As incineration time increased, yield of seaweed salts, insoluble solid content, and pH decreased, whereas ORP of the salt increased. Potassium content of seaweed salt with incineration time, while Ca and Na contents decreased after incineration of 8 and 4 hr, respectively. Yield of seaweed salt by osmotic dehydration increased as immersion time in sea water increased. pH of salt from sea mustard was higher than that of sea tangle. ORP of seaweed salt dried three times was -128.8 mV, significantly lower than that of salt prepared by incineration method. As sea water immersion time increased, Mg content of seaweed salt increased significantly, while Ca content decreased. Potassium content of seaweed salt was higher in sea tangle salt. In case of salt prepared by incineration of residuals, pH increased with immersion time but ORP decreased.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.2
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• pp.149-158
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• 2018

Agriculture is strongly influenced by climate change such as increased temperature and carbon dioxide ($CO_2$). This study describes the effects of climate change elevated $CO_2$, temperature, and relative drought on growth responses and yield in potato (Solanum tuberosum L.). The assessment was conducted for spring seasons in Soil-Plant-Atmosphere Research (SPAR) chamber at National Institute of Crop Science (NICS). Potatoes exhibit a positive response to $CO_2$ enrichment but water stress primarily reduces potato canopy and tuber yield. Elevated $CO_2$ and temperature increased both dry weight and tuber yield. Elevated $CO_2$ and temperature influenced SPAR 2 plants to a larger, and tuber increased yield up to 28% of than in SPAR 1(30-year average temperature at 450 ppm of $CO_2$). Our study findings indicate that tuber yield increase in potato under high $CO_2$ concentration was due to an increase in the size of individual tubers rather than in the number of the tubers per plant. On other hand, SPAR 3(30-year average temperature $+2.8^{\circ}C$ at 700 ppm of $CO_2$ under water stress) was lower than SPAR 2(30-year average temperature $+2.8^{\circ}C$ at 700 ppm of $CO_2$) nearly 56% of tuber yield due to drought. The results confirm potato drought sensitivity in terms of yield response. The experiment also showed that, in the conditions of climate change, climate change scenarios that improve cropping systems with potato.

• Journal of the Korean Wood Science and Technology
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• v.16 no.1
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• pp.21-44
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• 1988

As a way for the effective utilization of pallman chips and sawdusts, these furnish materials were combined with non-woody material of plastic (polypropylene) screen in board manufacturing to improve their weak physical and mechanical properties. The conventional boards were made with conditions of specific gravity 0.40, 0.55, 0.70, and 0.85, resin content 8, 10, 12 and 14%, and number of polypropylene screen 1, 2, 3 and 4, and press-lam boards were also manufactured. The physical and mechanical properties were measured and discussed on thickness swelling, bending modulus of rupture and elasticity, tensile strength, internal bond strength, and screw holding strength. The results obtained at this study were summarized as follows: 1. In thinckness swelling both of pallman chip board and sawdust board were improved by the increase of resin content, and press-lam boards showed lower thickness swelling than conventional boards. 2. Both the modulus of rupture and elasticity were increased with the increase of specific gravity, and press-lam boards showed higher modulus of rupture and elasticity than conventional boards. On the other hand, modulus of rupture was increased with the increase of number of polypropylene screen and resin content whereas these effects in modulus of elasticity was not recognized. 3. Tensile strength was increased with the increase of specific gravity, and the boards combined with polypropylene screen showed higher tensile strength than control boards. Also tensile strength was increased with the increase of number of polypropylene screen, and press-lam boards revealed higher tensile strength than conventional boards. 4. Internal bond strength was increased with the increase of specific gravity, and the boards combined with polypropylene screen were lower in internal bond strength than control boards. Also, the boards combined with odd number of polypropylene screen showed lower internal bond strength than those combined with even number of polypropylene screen. 5. Screw holding strength was increased with the increase of resin content and specific gravity but significant difference was not approved between boards combined with polypropylene screen and control boards. In press-lam boards, pallman chip boards of higher specific gravity but sawdust boards of lower specific gravity showed better screw holding strength than control boards.

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.1
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• pp.18-22
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• 2002

This experiment was conducted to investigate the effect of night illumination on the growth and yield of wheat and barley. Three varieties of barley and four cultivars of wheat were tested under the different night illuminance which was controlled in the range of 1.2∼20 Lux during whole growth season at night. As night illumination was stronger, the culm length of all varieties tended to be shorter. The shortening was greater in barley than wheat. Node number, awn length and culm diameter tended to decrease as the light intensity was stronger. Internode length above the 4th and 5th node was remarkably decreased by the stronger illuminance. The degree of decrease in spike length affected by the night illuminance was much larger in the late-maturing variety among wheat cultivars. As night illumination was stronger, days to heading was shortened in general. The range of decrease was 2 to 10 days under 10∼20 Lux condition similarly in both barley and wheat. Effect of night illumination on heading date and days from initial heading to full heading was not considerably different between the crops and among varieties except Kangbori. Night illumination decreased the grain yield by 12.5% in barley, and 11.0% in wheat at 2.1∼5.0 Lux condition, and 34.6% in barley, and 29.3 % in wheat at 10∼20 Lux condition compared to control. Yield reduction was significantly different among varieties, being greatest in Kangbori among barley varieties, and in Chokwang (late-maturring variety) and Changkwang (late-maturring variety) among wheat varieties. It was interpreted that the decrease of grain yield was resulted from the decrease in the number of spikes and the number of grains per spike under the stronger night illumination. The decrease of grain yield was more directly attributed to the decrease in the number of grains per spike.