• Korean Journal of Soil Science and Fertilizer
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• v.12 no.1
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• pp.15-23
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• 1979

In the first paper of the series the five soil fertility factors were evaluated by means of principal component analysis and varimax method. They are interpreted as representing, 1) skeletal available phosporus status, 2) organnic matter status, 3) salt status 4) base status, and 5) free oxide status. In order to resynthesize such fragmented information for the overall soil fertility evaluation, the method of multiple regression analysis was adopted, using the five factor scores and yield data for Korean paddy soils as independent and dependent variables respectively. As test of linear models with different combinations of independent variables the results of t-test of regression coefficient were revealed that the organic matter status (FII) has no relevance to the yield of paddy and that the free oxides and salt supply has by it self only an insignificant contribution to the yield. The multiple correlation coefficient (R) revealed its multiple regression analysis was as low as 0.43. Introduction of quadratic terms to the linear model bettered the result. Thus multiple correlation coefficient (R) was increased as 0.59. Therefore, a coefficient of determination 0.35 was obtained by a quadratic model with interaction terms among the five fertility constituents. Generally we think that the fertility factor has more contribution to raise the rice yield in paddy and that the failure of yield prediction by fertility factor scores was caused by one of follows; 1) the roughness of the yield inspection, and 2) missextraction of fertility constituents. The second step in this study, assuming that the residuals by multiple regression analysis were due to factors other than soil fertility, we can now proceed to predicting the yield from the field characters with the classified fertility groups by means of Hayashi's theory of quantification No. 1. Such variables as fertility groups (FTYG), water availability (WATER), soil drainage (DRNG), climatic zone (CLIZ), surface soil's stickiness (STCKT), surface soil's dry consistence (DCNST), and surface soil's texture (FTEXT) are taken up as the explanatory variables. The quantification appears reasonable; the well to extremely well in soil drainage, very sticky of surface soil, inefficiency in water availability, coarse texture, and very hard to extremely hard dry consistence in soil are detrimental to the rice yield. The R was as high as 0.90 for the set of variables. But the given explanatory variables in this study were not quite effective in explaining rice yield. The method developed seems to be promising only if properly collected data are available. Conditions that should be satisfied in the yield inspection obtained from common cultivator for the purpose of deriving a prediction equation were put forward.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.4
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• pp.260-264
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• 1991

To investigate the proper fertilization position in the soil accumulated with phosphorus and salt, tomato, Seo-Kwang, was planted on the bottomless pot, 45cm diameter 30cm length, filled with three different soils ranged 567 to 1,140 ppm of available phosphorus (0.45~3.69 mmhos/cm in electrical conductivity). Fertilizer phosphorus was treated at three different sites of side 0~5,6~10, 11~15cm and three different sites of depth; 0~5, 6~10, 11~15cm, The results are follows; Fertilizer use efficiency (FUE) of phosphrous of tomato was decreased as avilable phosphorus in soil increased. Highest FOE of phosphorus was showed at band application of feliilizer phosphorus at 0~5cm side and 11~15cm depth in the soil contain ing 567ppm of available phosphorus, and 6~10cm side and 0~5cm depth in the soils containing 942 and 1,140ppm of phosphorus. At 45 days after planting tomato root was highly distribued to 0~5cm side and depth respectively in low salt soil (0.45mmhos/cm), 11~15cm depth in 2.61mmhos/cm soil and 6~10cm depth in 3.69mmhos/cm. The fertilizer use efficiency of phosphorus of tomato plant war negatively significantly correlated with soil EC and phosphate concentration at 45 days after planting. The fertilizer use efficiency of phosphorus was more highly correlated with available phosphorus than electrical conductivity in soil.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.6
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• pp.29-36
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• 2008

This study examined the de-icing agents' stresses on Pinus strobus and Pinus thunbergii by chlorophyll fluorescence analysis. The assumption of this study was that photosynthetic efficiency was changed by de-icing agents applied onto highways in winter by altering the concentration of the de-icier, types of de-icer and leaf surface coating liquid application. The practical purpose of this study was to investigate the de-icing gents stresses on Pinus strobus by the highway area where de-icing agents were used frequently and to discover out minimizing stratages to prevent further damages. or this simulation study, a sample plot was established in Bogae-myeon, Anseong, Gyeonggi-do and Pinus strobus and Pinus thunbergii were planted for the examination in April, 2005. Five types of de-icing agents - NaCl, $CaCl_2$, T product(NS40:low cWoride de-icer type), NaCl+$CaCl_2$ and T product+$CaCl_2$ - were selected and the their concentration was altered to 0%, 5%, and 9%. Five types of de-icing agents were applied to both trees treated by a leaf surface coating liquid and trees not treated by leaf surface coating liquid. For the fluorescence analysis, the leaf surface coating liquid, which was diluted by 10 times, was sprkinkled onto the two tree species three days prior to gathering samples. Sample leaves from the two tree species were gathered at 10 o'clock in the morning of mid-August, 2006 and brought to the laboratory within three hours to be dipped in different concentrations (0%, 5%, or 9%) of the five de-icing agents for two minutes. Then the eaves were placed on the filter paper dipped in each solution on a petri dish, sealed with polyethylene film and kept in a growth chamber at $22^{\circ}C$ for 72 hours. Out of the growth chamber, the leaves were treated with a chorophyll fluorescence reaction analyzer for 30 minutes to measure the initial light acceptance rate(Fo), maximum light acceptance ate(Fv/Fm), light acceptance usage(F' q/F' m) and optical electron delivery coefficient(qP). As a result, Pinus strobus' initial light acceptance rate(Fo) decreased as T product and NaCl increased in concentration, and $Cal_2$ did not reduce much with the eaf surface coating liquid application. Maximum light acceptance rate(Fv/Fm) and light acceptance usage(F' q/F' m) decreased sharply as T product and NaCl increased in concentration and NaCl+$CaCl_2$ and T product+$CaCl_2$ did not reduce much with leaf surface coating liquid application. Optical electrons delivery coefficient (qP) decreased as T product increased in concentration on trees without the leaf surface coating liquid application and all other de-icing agents did not show much reduction. As for Pinus thunbergii, the initial light acceptance rate(Fo) decreased as T product increased in concentration, but the maximum light acceptance rate(Fv/Fm) was not reduced much by changes in concentration. light acceptance usage(F' q/F' m) decreased as NaCl increased in concentration and optical electron delivery coefficient(qP) decreased as NaCl increased in concentration in both with and without leaf surface coating liquid application. In conclusion, it was possible to plant Pinus strobus if spraying leaf surface coating liquid or cleaning deicing salt to prevent the damage caused by deicing agents was more economical than replacing the trees. If not, it was better to plant Pinus thunbergii. Another way to decrease the deicing gents stresses of landscape plants would be planting the trees further away from the roads even though it might take longer period to display its planting functions.

• 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.

• Journal of the Korean Society of Food Culture
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• v.2 no.1
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• pp.33-43
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• 1987

The cooking processes of Yackwa writen in 27 Korean books were reviewed. The changes of the names, shapes, materials and methods of dough, and the methods of frying, the materials and methods of soaking, garnishes were reviewed based on the historical literatures. 1. The changes of names of Yackwa were Yackwa, Kwajul, Chokwa and the shapes were bird, animal, round or cubic. The diameter was about 3.5cm, and thickness was from 0.5cm to 1.5cm. 2. The major ingredients of Yackwa were flour, honey, sesame oil and alcohol beverages. Sometimes, soybean powder and rice powder were used instead of flour, and chochung, sugar water, sugar syrup were used instead of honey. Sesame oil was usually used but salad oil were used occasionally. Usually pure liquor, distilled spirits, rice wine, cloudy and coarse rice wine, whisky were used as alcoholic ingredient and water was used at boiling state. Sesame and sesame salt, ginger and ginger juice, pepper powder, pine nuts powder, salt were used as minor ingredients. 3. Though the flour was kneaded extensively or gently, the latter was peculier since 1940. 4. The dough was fried in oil at $120{\sim}160^{\circ}C$ for $5{\sim}15$ minutes. at that time, The shape will be broken if temperature of oil is too low and too harden if temperature is too high. 5. Fried dough was soaked in honey before 1940, but thereafter other sweeteners, such as chochung, syrup were also used. Ginger juice, dried ginger, citron juice were used for flavor. 6. For enhancing the flavor and softening excess oil was removed from the fried Yackwa, and then it was soaked in honey. 7. The garnishes of Yackwa were pine nuts powder, cinnamon powder, sugar, etc.

• Korean journal of food and cookery science
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• v.19 no.2
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• pp.165-173
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• 2003

This study was carried out to develop a better fruit-dressing than previous mayonnaise in terms of calories, salt content and color, using kiwis, oranges, strawberries, and apples. This study was aimed to identify the perception, physico-chemical and sensory characteristics of the 4-kinds of fruits dressing. The results were as follows: The perception of the fruit dressings received the highest score (3.90) for 'It's convenience foods'. The misture in the dressings ranged from 49.3 to 59.4%, and was highest in apple dressing, followed by the kiwi, strawberry, and orange dressings, in that order. The crude ash for the dressings ranged from 0.8 to 1.4%, and was highest in the orange dressing. The L value was highest in the apple dressing, the a(-) value in the kiwi dressing, the a(＋) value in the strawberry dressing and the b value in the orange dressing. The Ca/ P ratio was about 1.17 : 1. The results of mineral contents analyses were also examined. The calcium, magnesium and potassium levels were highest in the orange dressing. The mineral contents of fruit dressings were 6.7 to 20.4mg/100g for calcium, 6.5 to 20.5mg/100g for magnesium and 67.2 to 182.6mg/100g for potassium. The sodium content of the fruit dressings were lower than in the previous mayonnaise, especially for the kiwi-dressing, which was 30% that in the mayonnaise. As a result of the sensory evaluations of the 4-kinds of fruits dressing, the kiwi dressing received the highest scores (3.50) of all the fruit-dressings in relation to the taste and palatability. Fruit are good for producing dressings that are low in calories and salt, with kiwi dressing proving to be the best of those fruits tested.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.90-104
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• 2001

This study is aimed to analyze and to evaluate the revegetation and soil conservation technology in desertification-affected sandy land, resulting from the project of "Studies on the desertification combating and sand industry development". Main native plants for combating desertification : The general characteristics of vegetation distribution in desertified regions are partially concentrated vegetation distribution types including the a) desert plants in low zone of desert or sanddune of depressed basin, b) salt-resistant plants around saline lakes, c) grouped vegetation with Poplar and Chinese Tamarix of freshwater-lakes, saline-lakes and river-banks, d) gobi vegetation of gravel desert and e) grassland and oasis-woods around the alluvial fan of rivers, etc. Generally, Tamarix ehinensis Lour., Haloxylon ammodendron Bunge., Calligonum spp., Populus euphratica Oliver., Elaeagnus angustifolia L., Ulmus pumila L., Salix spp., Hedysarum spp., Caragana spp., Xanthoceras sorbifolia Bunge., Nitraria tangutorum Bobr., Lespedeza bicolor, Alhagi sparsifolia Shap., Capparis spinosa L., Artemisia arenaria DC., etc. are widely distributed in desertified regions. It is necessary for conducting research in the native plants in desertified regions. Analysis of intensive revegetation technology system for combating desertification : In the wind erosion region, the experimental research projects of rational farming systems (regional planning, shelterbelts system, protection system of oasis, establishment of irrigation-channel networks and management technology of enormous farmlands, etc.), rational utilization technology of plant resources (fuelwood, medicinal plants, grazing and grassland management, etc.), utilization technology of water resources (management and planning of watershed, construction of channel and technology of water saving and irrigation, etc.), establishment of sheltetbelts, control of population increase and increased production technology of agricultural forest, fuelwood and feed, etc. are preponderantly being promoted. And in water erosion region, the experimental research projects of development of rational utilization technology of land and vegetation, engineering technology and protection technology of crops, etc. are being promoted in priority. And also, the experimental researches on the methods of utilization of water (irrigation, drainage, washing and rice cultivation, etc.), agricultural methods (reclamation of land, agronomy, fertilization, seeding, crop rotation, mixed-cultivation and soil dressing works, etc.) and biological methods (cultivation of salt-resistant crops and green manure and tree plantation, etc.) for improvement of saline soil and alkaline soil in desertified-lands are actively being promoted. And the international cooperations on the revegetation technology development projects of desertified-lands are sincerely being required.

• Korean Journal of Remote Sensing
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• v.22 no.6
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• pp.495-505
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• 2006

In order to classify aerosol type, Aerosol Optical Thickness (AOT) and Fine mode Fraction (FF), which is the optical thickness ratio of small particles$(<1{\mu}m)$ to total particles, data from MODIS (MODerate Imaging Spectraradiometer) aerosol products were analyzed over North-East Asia during one year period of 2005. A study area was in the ocean region of $20^{\circ}N\sim50^{\circ}N$ and $110^{\circ}E\simt50^{\circ}E$. Three main atmospheric aerosols such as dust, sea-salt, and pollution can be classified by using the relationship between AOT and FF. Dust aerosol has frequently observed over the study area with relatively high aerosol loading (AOT>0.3) of large particles (FF<0.65) and its contribution to total AOT in spring was up to 24.0%. Pollution aerosol, which is originated from anthropogenic sources as well as a natural process like biomass burning, has observed in the regime of high FF (>0.65) with wide AOT variation. Average pollution AOT was $0.31{\pm}0.05$ and its contribution to total AOT was 79.8% in summer. Characteristic of sea-salt aerosol was identified with low AOT (<0.3), almost below 0.1, and slightly higher FF than dust and lower FF than pollution. Seasonal analysis results show that maximum AOT $(0.33{\pm}0.11)$ with FF $(0.66{\pm}0.21)$ in spring and minimum AOT $(0.19{\pm}0.05)$, FF $(0.60{\pm}0.14)$ in fall were observed in the study area. Spatial characteristic was that AOT increasing trend is observed as closing to the eastern part of China due to transport of aerosols from China by the prevailing westerlies.

• Journal of Life Science
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• v.23 no.9
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• pp.1147-1154
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• 2013

This study was conducted to evaluate the antioxidation activity of Jeju crossbred horse (Jeju native horse ${\times}$ thoroughbred) leg bone extracts (HLBE) and its enzyme hydrolysates by determination of 1,1-diphenyl-2picryl-hydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzo thiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity, ferric reducing/antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC). HLBE was extracted with hot water for 24 hr and lyophilized. The lyophilized HLBE was hydrolyzed using multifect PR6L (MP), pepsin (PS), and a pepsin and pancreatin mixture (PSPC) for 4 hr at 60, 50, and $50^{\circ}C$, respectively. The hydrolysates were separated by a molecular weight of 3 kDa more or less. When the yield of HLBE was 100%, the yield of hydrolysates less than 3 kDa of MP, PS, and PSPC was 10.86, 3.26, and 8.00%, respectively. Enzyme hydrolysates with low molecular weight less than 3 kDa in MP and PSPC showed significantly higher DPPH, ABTS radical scavenging activity, and ORAC compared to HLBE and its hydrolysates with more than 3 kDa. However, the FRAP of the hydrolysates less than 3 kDa in PS was significantly higher than in MP. These results suggest that low molecular weight enzyme hydrolysates less than 3 kDa have more powerful antioxidation activity, especially when they are hydrolyzed by MP and PSPC rather than PS. Therefore, low molecular weight enzyme hydrolysates of HLBE hydrolyzed with MP and PSPC have significant potential as antioxidants in the food industry. Further in vivo studies are required to support the antioxidation activities of the hydrolysates in vitro.

• Journal of Soil and Groundwater Environment
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• v.12 no.2
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• pp.27-36
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• 2007

A recent study showed that MTBE can be degraded by Fenton's Reagent (FR). The treatment of MTBE with FR, however, has a definite limitation of extremely low pH requirement (optimum pH $3{\sim}4$) that makes the process impracticable under neutral pH condition on which the ferrous ion precipitate forming salt with hydroxyl anion, which result in the diminishment of the Fenton reaction and incompatible with biological treatment. Consequently, this process using only FR is not suitable for in-situ remediation of MTBE. In order to overcome this limitation, modified Fenton process using NTA, oxalate, and acetate as chelating reagents was introduced into this study. Modified Fenton reaction, available at near neutral pH, has been researched for the purpose of obtaining high performance of oxidation efficiency with stabilized ferrous or ferric ion by chelating agent. In the MTBE degradation experiment with modified Fenton reaction, it was observed that this reaction was influenced by some factors such as concentrations of ferric ion, hydrogen peroxide, and each chelating agent and pH. Six potential chelators including oxalate, succinate, acetate, citrate, NTA, and EDTA were tested to identify an appropriate chelator. Among them, oxalate, acetate, and NTA were selected based on their remediation efficiency and biodegradability of each chelator. Using NTA, the best result was obtained, showing more than 99.9% of MTBE degradation after 30 min at pH 7; the initial concentration of hydrogen peroxide, NTA, and ferric ion were 1470 mM, 6 mM, and 2 mM, respectively. Under the same experimental condition, the removal of MTBE using oxalate and acetate were 91.3% and 75.8%, respectively. Optimum concentration of iron ion were 3 mM using oxalate which showed the greatest removal efficiency. In case of acetate, $[MTBE]_0$ decreased gradually when concentration of iron ion increased above 5 mM. In this research, it was showed that modified Fenton reaction is proper for in-situ remediation of MTBE with great efficiency and the application of chelatimg agents, such as NTA, was able to make the ferric ion stable even at near neutral pH. In consequence, the outcomes of this study clearly showed that the modified Fenton process successfully coped with the limitation of the low pH requirement. Furthermore, the introduction of low molecular weight organic acids makes the process more available since these compounds have distinguishable biodegradability and it may be able to use natural iron mineral as catalyst for in situ remediation, so as to produce hydroxyl radical without the additional injection of ferric ion.