• Korean Journal of Soil Science and Fertilizer
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• v.32 no.2
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• pp.132-139
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• 1999

A field experiment was conducted at Cheju from early March 1998 to early March 1999 to evaluate the effects of foliar applied urea on leaf N content and N recovery in satsuma mandarins (Citrus unshiu Marc.). Seven years old 'Okitsu Wase' trees received foliar spray of urea (22 or 43 g N $tree^{-1}yr^{-1}$) or soil application of urea (86 g N $tree^{-1}yr^{-1}$). 56% of N was applied in spring, 11% in summer and 33% in fall. There were seven trees per N treatment and two trees per N treatment received $^{15}N$-labeled urea in spring and summer to determine N recovery. There were no differences between the treatments for fruit yield and its quality. Nitrogen content of spring flush leaf blades up to early September was greater for trees received foliar spray comparing with soil application but was not greatly affected by any treatment after mid-November. The recovery of fertilizer N in various parts of trees receiving foliar spray of 22 g N $tree^{-1}yr^{-1}$ was greatest, followed by receiving foliar spray of 43 g N and soil application of 86 g N. The recovery of fertilizer N in tree was 29.2 and 17.7% for foliar spray of 22 and 43 g N $tree^{-1}yr^{-1}$, respectively and 8.0% for soil application of 86 g N $tree^{-1}yr^{-1}$. The recovery of fertilizer N in the upper 40 cm of soil was 50.3, 45.6, and 51.8% for foliar spray of 22 and 43 g N $tree^{-1}yr^{-1}$, and soil application of 86 g N $tree^{-1}yr^{-1}$ respectively. The total (tree, fallen leaves, winter weeds, and soil) recovery of fertilizer N was 81.8, 65.1, and 60.6% for foliar spray of 22 and 43 g N $tree^{-1}yr^{-1}$, and soil application of 86 g N $tree^{-1}yr^{-1}$, respectively.

• Applied Biological Chemistry
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• v.37 no.4
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• pp.277-286
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• 1994

The pot experiment using $^{15}N$ isotope dilution technique was carried out to calculate the balance of nitrogen of surface applied urea in the rice-soil system. The $^{15}N$ concentration was determined by stable isotope ratio mass spcetrometer (model: VG ISO-GAS MM622). In the pots with $^{15}N$ labeled urea application at the rates of 15 and 30 kg N/10a, the percentage of nitrogen derived from fertilizer (NDFF) in rice was higher at the rate of 30 kg N/10a (average 89%) than at the rate of 15 kg N/10a (average 64%). However, the recovery as percentage of fertilizer N by rice was higher at the rate of 15 kg N/10a (65.5%) than at the rate of 30 kg N/10a (54.2%). The percentage of the fertilizer N remained in extractable inorganic N form at the rates of 15 and 30 kg N/10a were $13.5%\;(NH_4-N\;5.53%,\;NO_3-N\;7.99%)$ and $16.5%\;(NH_4-N\;7.49%,\;NO_3-N\;8.98%)$ in unplanted soil, and $2.0%\;(NH_4-N\;0.63%,\;NO_3-N\;1.32%)$ and$2.3%\;(NH_4-N\;0.87%,\;NO_3-N\;1.40%)$ in soil planted to rice, respectively. The dominant form of inorganic-N in soil after harvest was $NO_3-N$ form rather than $NH_4-N$ form regardless of urea application rate or rice cultivation. The percentage of the fertilizer N remained in organic N form at the rates of 15 and 30 kg N/10a were 65.0 and 41.8% in unplanted soil, and 23.7 and 26.9% in soil planted to rice, respectively. In conclusion, the efficiency of surface-applied urea was greater at the rate 15 kg N/10a than at the rate of 30 kg N/10a.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.2
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• pp.123-133
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• 2011

Purpose: The present study was conducted to analyze any difference in the movement of aspheric RGP lens by the amounts of keratometiric astigmatisms using keratometer and corneal topography. Methods: Corneal curvatures in thirty six eyes of males and females of with-the-rule keratometric astigmatisms in their twenties were measured by a keratometer and worn aspheric RGP lenses. Then, lens rotations, vertical and horizontal movements of lens by blinking were measured to compare with lens movements when aspheric RGP lenses were fitted by total keratometric astigmatisms using corneal topography. Results: The case having higher amount of central keratometric astigmatism was 61.1% of subjects, however, 36.1% of subjects showed higher total keratometric astigmatism indicating that central keratometric astigmatism was not always bigger than total keratometric astigmatism. Since over 0.25 diopter difference between total and central keratometric astigmatisms was shown in 19 eyes (52.8% of subjects), the prescription for lens fitting could be changed. Significant difference in horizontal movement was detected with increase of astigmatism when it compared based on the amount of keratometric astigmatism measured by a keratometer. However, there was no significant difference in lens rotation, horizontal and vertical movements by comparison with the amount of total keratometric astigmatism using a corneal topography. When central keratometric astigmatism measured by keratometer was bigger than total keratometric astigmatism estimated by corneal topography, bigger lens rotation was shown compared with opposite case. Also, the tendency of bigger lens rotation was measured with the increase of keratomatric astigmatism in the case of same prescription having same base curves with same amount of keratometric astigmatism but different curvatures. Conclusions: From the present study, we concluded that lens movements on cornea were not totally different when aspheric RGP lens fitted on with-the-rule astigmatism by keratometer and corneal topography. However, there was some difference in certain lens movements. Therefore, we concluded that further study on the relationship between the prescriptions for lens fitting should be conducted for improving the rate of successful lens fitting by keratometer or for the proper application of corneal topography for lens fitting.

• Journal of Sericultural and Entomological Science
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• v.32 no.2
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• pp.89-93
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• 1990

Mulberry, damaged by a late frost on April 27, received a foliar spray of 0.5% Urea or Jambi(a foliar fertilizer). The sprays were applied once every 3 days from May 16 for 12 days. The results were : 1. Approximately 70 auxillary buds per tree sprouted after the frost. The difference between the lowest and highest number of buds was 3 to fold. 2. For the 25 days beginning May 18, shoot length increased 5.4 fold, leaf number 2.1 fold, and shoot weight 9.6 fold. 3. Yield from latent buds was about 5% of total yield. 4. Length of new shoots decreased 26% due to frost. Urea spray and Jambi increased shoot length 10% and 1%, respectively, compared to control. 5. Leaf number decreased by 5.2 due to frost. Urea spray and Jambi increased leaf number 18% and 5%, respectively, compared to control. 6. Weight of new shoot was decrease 43% by frost. Urea and Jambi spray increased shoot weight 7% and 6%, respectively, compared to control. 7. Net leaf yield decreased 47% due to frost. Urea spray and Jambi increased left yield 7% and 5%, respectively, compared to control. 8. Yield in an undamaged plot was 1,587kg, damaged 932kg, 1,070kg in urea spray, and 1,033kg/10a in Jambi spray. Yield of frost damaged plots was 59% of undamaged. Foliar spray increased this to 68% of undamaged. 9. Yield increased 3.5% daily by with postponement of harvest. Yield of four days postponement was expected 73% of undamaged. Urea spray with 4 days postponement expected to be increased this to 82% of undamaged.

• Journal of Wetlands Research
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• v.11 no.3
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• pp.61-70
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• 2009

Seasonal changes of flora, vegetation structure, and primary production for the vascular plants were investigated in the disturbed bank, Daedaejae, one of the reinforced bank of Upo wetland, in Changnyeong-gun, Gyeongsangnam-do, Korea from October 2005 to October 2006. The flora of the whole study area, the fabricated and the non-fabricated bank area were composed of 78, 72, 75 taxa, respectively. Among all of them, hydrophytes, hygrophytes, and mesophytes were 3, 33, and 42 taxa, respectively. The naturalized plants were 20 taxa, which was 25.6% of 78 taxa distributed in the study area. Dominant species of the fabricated and the non-fabricated bank area was Equisetum arvense and Trifolium repens, respectively. Importance values of the naturalized plants such as Erigeron annuus, Humulus japonicus, Astragalus sinicus and Ambrosia artemisiifolia var. elatior were relatively high in both area. The species diversity indices(H') were 1.010~1.450, and those were relatively high in October and low in March in both area. Those of the non-fabricated bank area was higher than the fabricated bank area during the whole study period. The similarity indices(CCS) between two kinds of banks were 0.359~0.456, and was lowest in March and highest in August, the culmination period of the vascular plants. Net primary production in the fabricated bank area was $417.1\;g/m^2$, and those of Phragmites communis, Oenothera odorata, Miscanthus sacchariflorus were 179.5, 84.0, and $66.1\;g/m^2$, respectively. Net primary production in the nonfabricated bank area was $392.7\;g/m^2$, and those of Erigeron canadensis, Miscanthus sacchariflorus, and Phragmites communis were 102.5, 87.4, and $81.6\;g/m^2$, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1043-1048
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• 2012

We have researched the changes of paddy soil properties and rice yield by several different methods to treated with liquid pig manure(LPM). In the execution of this experiment, rice was cultivated to full maturity at a paddy field in Jeollabuk-do in 2011. Field experiment was designed with surface application on dry field condition+jet hose spray(Tr. 1), surface application on dry field condition+incorporation with irrigation water(Tr. 2), surface application on dry field condition+application device of fertilizer through irrigation(Tr. 3), submerged application on irrigated field condition+jet hose spray(Tr. 4), submerged application on irrigated field condition+incorporation with irrigation water(Tr. 5) and submerged application on irrigated field condition+application device of fertilizer through irrigation(Tr. 6) plot. Total N, P, K contents in used LPM were 0.44%, 0.07% and 0.14%, respectively. After the experiment, soil properties were not significant difference both several treated plots. But $NO_3$ and $NH_4$ contents at incorporation with irrigation water plots in paddy soil were higher than other plots. The yield was 602 kg $10a^{-1}$ in Tr. 2 plot compared Tr. 6 plot, which showed a value of 9.6% higher.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.5
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• pp.253-263
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• 2002

To test for the effect of applied fertilizer and nutrients on uptake and transport for paddy rice, two paddy field trials were conducted with Dongjinbyeo in degenerated salt paddy field of Jeonbuk series from 1999 to 2000. After experiment, soil acidity, content of organic matter phosphate, silicate, potassium, calcium, and total nitrogen was increased by application of fresh cattle manure(FCM). Content of Nitrogen in soil layer leached inorganic nitrogen $NO_3$ was higher that that of $NH_4$ and was high in treatment of FCM. Content of $PO_4$ was higher in FCM than other treatments. But content of potassium was in high control. During the growth of rice plant, the amount of water consumption was 477mm. The amount of supplied nitrogen was high in treatment of no nitrogen(NN), 20% reduced application of LCU(LCU-20%), and no fertilizer. In case of phosphate, the supplied amount was more than the consumed amount with the exception of treatment "no phosphate(NP) and no fertilizer(NF)". In case of potassium, the consumed amount was more than the supplied amount in all treatments. The amount of applied nitrogen in the nutrient infiltrated water was high in treatment soil test(ST), C+FCM+Si(Silicate) and the ratio of recovered nitrogen was high in 20% reduced application of LCU. The amount of applied phosphate in the nutrient infiltrated water was high in FCM and that of applied potassium was high in 20% reduced application of LCU. Nitrogen use efficiency of paddy rice was high in 20% reduced application of LCU and use efficiency of phosphate and potassium was high in C+Si(Silicate). Grain yield of rice was high in order of 20% reduced application of LCU>C+Si=C+FCM+Si>C+FCM.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.298-298
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• 2009

유기농업 토양에서 합리적인 유기물 관리를 위한 기초자료로 활용하기 위하여 밭토양에서 동일한 유기물을 9년간 연용하면서 옥수수의 건물량의 연차간 변화량을 조사하였다. 처리는 무비구(WF)를 비롯하여 화학비료 단용처리(CF), 화학비료 및 돈분왕겨퇴비 혼용(CF+CPR) 두었으며, 유기자원별로는 돈분왕겨퇴비(CPR), 채종유박(RC), 볏짚퇴비(CRS), 녹비(GM) 등 7처리를 두었고, 작물의 생산성은 줄기와 알곡을 포함한 총 건물량에 대하여 화학비료 단용구를 대조로 하여 상대비교하였다. 옥수수의 생육은 파종후 52일 및 수확기에 볏짚퇴비구와 녹비처리구에서 가장 양호하였다. 9년차 옥수수 총 건물량은 화학비료구 1,226kg/10a 대비 녹비처리구에서 121%로 높았으나 볏짚퇴비구 97%, 채종유박 92% 돈분왕겨퇴비 80%로 낮았으며, 무비구의 경우 24%의 수량을 보였다. 양분의 흡수량은 녹비처리구에서 11.8kg/10a로 화학비료구에 비하여 낮았으나 다른 유기자원 처리구보다 높았다. 질소 이용율은 녹비처리구 61.1%로 화학비료구 61.6%와 동일한 수준을 보였다. 화학비료구에 대한 상대적인 수량은 녹비처리구에서 5년차까지 증가하다가 6년차부터 점차 감소하는 경향(y=$-2.044x^2$+25.302x+51.402, $R^2$=0.8571)이었으며, 볏짚퇴비구도 7년차까지는 수량이 증가하다가 8년차부터 감소하는 경향(y=$-1.0621x^2$+13.091x+63.59, $R^2$=0.6643)을 보였다. 유기질비료구와 돈분왕겨퇴비구는 완만한 감소경향을 보였으나 무비구는 급격히 감소하는 경향이지만 점차 감소폭이 좁아지는 경향(y=$0.4584x^2$-9.5544x+69.221, $R^2$=0.8777)을 보였다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.2
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• pp.23-30
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• 1980

Experiments were conducted to know N, P, and K top dressing effects on yield and other agronomic characters of rice plants grown in 5-year differently fertilized soils. Four levels of nitrogen, 0, 1.2, 2.4, and 3.6kg/10a, were applied 32 days before heading in 5-year non-fertilized and PK applied plots. Four levels of P_2 $O_{5}$ and K_2 O of 0, 4, 8 and 12kg/l0a were applied 40 days before heading in 5-year NK and NP applied plots, respectively. 1. Heading was delayed by seven days in 5-year non-fertilized and PK applied plots compared to NK, NP, or NPK applied plots where nitrogen was applied as basal. However, in 5-year non-fertilized and PK applied plots heading was delayed from 1 to 4 days as amounts of nitrogen top dressing increased. Phosphorus and potassium did not affect heading date of rice plants. 2. In 5-year non-fertilized plot grain yield increased as amounts of nitrogen top dressing increased up to 2.4kg/l0a due to both increased number of panicles per hill and spikelets per panicle. However, in 5-year PK applied plot amounts of nitrogen top dressing did not affect grain yield; the number of panicle per hill increased, but the percentage of ripened grains and grain weight tended to decrease as nitrogen levels increase. 3. The number of panicle/maximum tillers ratio in percentage increased markedly as amounts of nitrogen top dressing increased in 5-year non-fertilized and PK applied plots with maximum value of 130% on the basis of maximum tillers at vegetative stage. 4. Top dressing of phosphorus and potassium did not affect yield and other agronomic characters in NK and NP applied plots.

• Journal of Korean Orthopaedic Sports Medicine
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• v.1 no.1
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• pp.15-20
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• 2002

Purpose: The purpose of this study is to evaluate diagnosis and treatment of acetabular labral tears in sports injuries. Materials and Methods: From March 1995 to January 2000, We treated 15 patients with acetabular labral tear by sports injuries. There were 6 men and 9 women. Mean age was 41 years old. Running injuries are 5 cases, fighting 3, aerobic exercise 3, swimming 2, climbing 1, bicycle 1. For conservative treatment, we performed medication and observation at least for 1 year. For the patients with arthroscopic surgery, we performed Harris Hip Score (pain and function) preoperatively and postoperatively at 6, 12 months, and evaluated patient’s pain by JOA pain scoring system and postoperative subjective satisfaction. Results: The mean score of HHS improved 15 points with conservative treatments and 32 points with hip arthroscopy. In 4 cases of conservative treatment, there was 1 scale improvement of JOA pain scoring system. In arthroscopic partial labrectomy, all cases were improved to more than 2 scale. Conclusion: We considered that acetabular labral tears occurred associated with sports injuries. So it is important to be interested in enthusiastic diagnosis and appropriate treatment for hip pain caused by sports injuries, especially about acetabular labral tears.