• 한국토양비료학회지
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• 제48권6호
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• pp.683-688
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• 2015

Nowadays, sustainable and environment-friendly agriculture has become an important issue all around the world, and repeated applications of mineral and/or organic fertilizer will probably affect mineral nutrient dynamics in soil in the long term but only a limited number of observations are available. This study was carried out to investigate whether there is any influence of different fertilizer management for red pepper (Capsicum annuum L.) cultivation on soil physicochemical properties, leaf mineral content, yield and fruit quality in the aspect of long-term practice in open field condition. NPK, NPK+compost, compost only, and unfertilized control plot were included in the treatments. The application of chemical fertilizer and/or compost repeated annually for 17 years from 1994 to 2011. Soil organic matter content was higher in compost treatments than in no-manure treatments. Available phosphate and the yield of red pepper were highest in NPK+compost treatment followed by NPK (chemical fertilizer), compost, and control. The results indicate that in the long term, nitrogen supply is still needed for increasing red pepper yield, but reduction in the use of chemical fertilizer could be also possible with the proper application of compost.

• Nuclear Engineering and Technology
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• 제53권1호
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• pp.344-350
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• 2021

As the High Flux Advanced Neutron Application Reactor (HANARO) has been recently required to support new R&D relevant to future nuclear systems requiring a much higher neutron fluence, the development of irradiation capsule technology for long-term irradiation testing was performed in three steps (3, 5, 10 dpa). At first, several design improvements of a standard capsule were suggested based on a failure analysis of the capsule and successfully applied for irradiation testing at HANARO at up to eight reactor operation cycles equivalent to 3 dpa. Based on a schematic stress analysis of the vulnerable parts of the previous capsule, an optimized design of the capsule was made for 5 dpa irradiation. The newly designed capsule was safely out-pile tested up to 450 days, which was equivalent to 5 dpa irradiation in the reactor. The test results were submitted to the Reactor Safety Review Committee of HANARO and irradiation testing for 5 dpa was approved. The capsule was also successfully out-pile tested to evaluate the possibility of irradiation testing for 10 dpa. For a higher neutron fluence exceeding 10 dpa, new capsule technologies, including a new capsule that has a different bottom design and neutron flux boosting capsule, were also suggested.

• 한국보건간호학회:학술대회논문집
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• 한국보건간호학회 2004년도 제1회 지역사회간호, 보건간호, 가정간호, 연합학술대회
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• pp.79-90
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• 2004

• 한국토양비료학회지
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• 제46권6호
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• pp.585-592
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• 2013

To estimate the effect of long-term fertilization on metabolically active bacterial communities in a rice field, RNA was extracted from endosphere (rice root), rhizosphere, and bulk soil that had been subjected to different fertilization regimes for 59 years, and the 16S rRNAs were analyzed using the pyrosequencing method. The richness and diversity of metabolically active bacteria were higher in bulk soil than in the endosphere and rhizosphere, and showed no significant difference between non-fertilized and fertilized plots. Weighted UniFrac analysis showed that each compartment had characteristic bacterial communities and that the effect of long-term fertilization on the structure of bacterial community was more pronounced in bulk soil than in the endosphere and rhizosphere. The 16S rRNAs affiliated with Alphaproteobacteria and Firmicutes were more abundant in the endosphere than in bulk soil while those affiliated with Chloroflexi and Acidobacteria were more abundant in bulk soil than in the endosphere. Several dominant operational taxonomic units (clustered at a 97% similarity cut-off) showed different frequencies between non-fertilized and fertilized plots, suggesting that the fertilization affected their activities in the rice field.

• 한국작물학회지
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• 제51권2호
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• pp.123-129
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• 2006

A long-term experiment was carried out to examine the effects of compost on the long-term trends and synergy effects with chemical fertilizer and saving the chemical fertilizers of paddy cropping. The experiment was conducted for the past 36 years with constant amounts of N, P, K and compost in a paddy field at Milyang, South Korea. Grain yield was significantly increased in the plots with compost application. Twenty five years after the compost treatment, grain yield was significantly increased and it reached almost 90% of NPK plots. The effect of rice straw compost on grain yield was not clear during the early cropping years about 60%, but it slightly increased there after about 95% during the late five years. In compost plots, soil organic matter content, K and $SiO_2$ was greater in the compost applied plots than with application of recommended doses of NPK. However, soil pH was reduced in compost applied plots and Ca, and Mg were remained unchanged when compared to the application of recommended doses NPK. Soil nutrient contents were less in compost applied plots than with the application of recommended doses of NPK along with compost but was found to be increased than that of un-fertilized plots. The present study indicated that the application of rice straw compost with NPK is the best of all and followed by NPK and Compost. However, treatment of Compost is time consuming and hard working desired and eventually non economical practice in mechanized agricultural systems, even though Compost is very useful source of improving the soil fertility and its physical characteristics and also the application of inorganic N and P are essential for sustaining high yield.

• Journal of the Optical Society of Korea
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• 제13권4호
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• pp.428-433
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• 2009

A photonic crystal fiber with two large air holes outside the holey cladding region is fabricated to induce an effective long periodic grating (LPG) in the core by an electric arc discharge. We believe that the two large air holes lead to the asymmetric perturbation in the core under the electric arc discharge, thereby introducing the coupling to the first higher-order mode. The transmission characteristics of the PCF with the LPG for the external perturbation such as strain, curvature, and temperature are also investigated. It was found that the shift of resonance peak in the transmission spectrum depends on the bending direction. The curvature of 8.55 $m^{-1}$ results in the center wavelength shifts of 1.8, 4.3, and 11 nm for a vertical, diagonal, and horizontal direction of the curvature to the large air-hole alignment, respectively.

• 대한원격탐사학회지
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• 제34권1호
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• pp.101-115
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• 2018

The Long Valley area and its surroundings are part of a major volcano system where inflation occurred in the resurgent dome in the 1990s. We used ENVISAT data to monitor surface deformation of the Long Valley area and its surroundings after the inflation, from 2003-2010. To retrieve the time series of the deformation, we applied the refined Small BAseline Subset (SBAS) algorithm which is improved using an iterative approach to minimize unwrapping error. Moreover, ascending and descending data were used to decompose the horizontal and vertical deformation in detail. To confirm refined SBAS results, we used GPS dataset. The InSAR errors are estimated as ${\pm}1.0mm/yr$ and ${\pm}0.8mm/yr$ from ascending and descending tracks, respectively. Compare to the previous study of 1990s over the Long Valley and its surroundings, Paoha Island and CASA geothermal area still subside. The deformation pattern in the Long Valley area during the study period (2003-2010) went through both subsidence (2003-2007) and slow uplift(2007-2010) episodes. Our research also shows no deformation signal near McGee Creek. Our study provided a better understanding of the surface changes of the indicators in the 1990s and 2000s.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1623-1626
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• 2005

The thiogallate phosphors which are well known for a long time as phosphor materials for CRT or EL device were reported. Those have high luminescent properties at long-wavelength region. Among those phosphors, the samples with divalent europium doped CaGa2S4 were prepared by a simple process under the reduction atmosphere $(5%\;H_2/\;95%\;N_2)$ without toxic gas such as H2S or CS2. The prepared phosphor shows a higher luminescent efficiency (about 120%) than that of $YAG:Ce^{3+}$ phosphor. Consequently, this phosphor is possible to be applicable to white LED lamp because of the high luminescent efficiency.

• Journal of Electrical Engineering and Technology
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• 제7권1호
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• pp.103-108
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• 2012

The present study describes the considerations on the long-term reliability of the on-line partial discharge (PD) ceramic sensor for thermal power generators. Voltage acceleration aging tests were carried out under continuous and impulsive thermal aging at more than $100^{\circ}C$, considering the practical service environment. Experimental results show that the sensors have a life that could last for more than 100 years, excellent dielectric characteristics, and insulation strength. In addition, the ceramic on-line PD sensors were installed in a thermal power generator in Korea for demonstration. The results of the PD calibration and test voltage application prove that the on-line ceramic sensors have satisfactory performances for on-line PD measurement.

• 식물병연구
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• 제25권2호
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• pp.89-93
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• 2019

Fire blight disease caused by the bacterium, Erwinia amylovora, was observed in apple and pear orchards in Korea in 2015. Since then, it has spread, sometimes over long distances to other orchards. Therefore, we examined the ability of E. amylovora to survive in soils and on the surfaces of common materials such as T-shirts, wrist bands, pruning shears, and rubber boots by both conventional PCR (cPCR) and quantitative PCR (qPCR) methods. E. amylovora was detected in all materials tested in this study and survived for sufficiently long periods to cause fire blight disease in new sites. Thus, based on the results of this study, sanitation protocols must be applied to equipment during orchard work.