• Journal of the Korean Magnetics Society
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• v.22 no.3
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• pp.79-84
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• 2012

Nano-magnetic materials such as iron-nitrides have been actively studied as an alternative to the application of high density, high performance needs for next generation information storage and also alternative to the rare earth and neodymium magnet. $Fe_4N$ is the basic materials for magnetic storage media and is one of the important magnetic materials in focus because of its higher magnetic recording density and chemical stability. Single phase ${\gamma}^{\prime}-Fe_4N$ nanoparticles have been prepared by a PAD (Plasma Arc Discharge) method and nitriding in a $NH_3-H_2$ mixed gases at temperature, $400^{\circ}C$ for 4 hrs. Also $Fe_{17}Sm_2N_x$ powders were synthesized by nitriding after reduction/diffusion of $Fe_{17}Sm_2$ to compare the magnetic properties with nano-sized $Fe_4N$ particles. The saturation magnetization of $Fe_4N$ and $Fe_{17}Sm_2N_x$ were 149 and 117 emu/g, respectively, but the coercive force was considerably smaller than that of bulk or acicular $Fe_4N$.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.629-637
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• 2000

A two-phase anaerobic reactor with a submerged microfiltration system was tested for its ability to produce methane energy from organic wastewater. A membrane separation system with periodic backwashing with compressed air was submerged in the acidogenic reactor. The cartridge type of microfiltration (MF) membrane with pore size of $0.5{\mu}m$ (mixed esters of cellulose) was tested. An AUBF (Anaerobic Upflow Sludge Bed Filter: 1/2 packed with plastic media) was used for the methanogenic reactor. Soluble starch was used as a substrate. The COD removal was investigated for various organic loading with synthetic wastewater of 5,000 mg starch/L. When the hydraulic retention time (HRT) of the acidogenic reactor was changed from 10 to 4.5 days, the organic loading rate (OLR) varied from 0.5 to $1.0kg\;COD/m^3-day$. When the HRT of the methanogenic reactor was changed from 2.8 to 0.5 days, the OLR varied from 0.8 to $5.8kg\;COD/m^3-day$. The acid conversion rate of the acidogenic reactor was over 80% in the 4~5 days of HRT. The overall COD removal efficiency of the methanogenic reactor showed over 95% (effluent COD was below 300 mg/L) under the highly fluctuating organic loading condition. A two-phase anaerobic reactor showed an excellent acid conversion rate from organic wastewater due to the higher biomass concentration than the conventional system. A methanogenic reactor combined with sludge bed and filter, showed an efficient COD and SS removal.

• Journal of the Korean Chemical Society
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• v.44 no.6
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• pp.526-532
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• 2000

Cation exchange separation and inductively coupled plasma atomic emission spectrometric(ICP-AES) determination of ruthenium in HCl solutions were studied to quantitatively determine ruthenium in spent nuclear fuels. Ruthenium-bearing samples were dissolved with the mixed acid solution(9 : 1 mole ratio, HCl-HNO$_3$) using an acid digestion bomb. Based on the absorption spectra and ion exchange behaviour of ruthenium in hydrochloric acid media, its possible chemical species were discussed. On a cation exchange column (0.7 ${\times}$ 8.0 cm) packed with AG 50W ${\times}$ 8(100~200 mesh) and equilibrated with 0.5 M HCl, ruthenium was eluated with 0.5 M HCl while uranium was retained on the column. The established separation method was applied to a simulated spent nuclear fuel and resulted in the recovery of 98.5% with a relative standard deviation of 0.7%.

• Journal of Korean Academy of Nursing
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• v.7 no.1
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• pp.30-38
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• 1977

Breast cancer is one of the most feared health problems in women ; Recent studies revealed that it had come up to be the second most in this country and high prevalent disease in the western countries among breast disease in women. However, early detection of the cancer mass is known to be easier than in many other malignancies. This study was performed to investigate the various characteristics of patients of breast cancer ; by the structural variables, menstrual, marital, and child bearing, and also their understandings and attitude towards the disease. A hundred any in- and out- patients of 51. Mary's Hospital and National Atomic Institute, Seoul were sampled. Data were gathered through direct interview by the researcher from February 1976 to January 1977 and the clinical records were used as references. Results are as follows ; 1. Breast cancer revealed to be most prevalent in the forties ; average age of 45.2 years. 2. The average age of menarche revealed to be 15.4 years ; the largest group were the 16-20 years (N=75, 68.2%). In 55 cases (50%) menstruation were normal, 38 (34.5%) postmenopausal and only in 17 (15.5%), menstruation revealed irregularity. 3. The average marital age revealed to be 22.3 years ; the largest group were 21-25 group (N=43, 39.1%). The average duration of marital life revealed to be 24.7 years ; 11-20 years group were the largest (M=34, 30.9%). 4. Most of the patients revealed to have pregnancy experiences(N=100, 90.9%) ; the average rate of experience were 5, 3 times the largest group were 3.4 times group(N= 32, 29.1%). 54 patients (49.1%) revealed to have had abortion experience ; the average were 3.4 times. 5. The largest group(N=77, 70%) had been breast feeding : followed by mixed feeding (N=12, 10.9%) and artificial feeding(N=10, 9.1%). 6. Personal health history revealed that in 20 patients (18.2%) revealed to have the past history of Purulent mastitis, 5 patients(4.5%) of breast cancer and 3 patients(2.7%) of uttering cancer family history. 7. In the one half (N=56, 50.9%, they had some information about breast cancer :27 (24.5%) by mass media, 12 (10.9%) through personal contacts and 17 (15.5%) were not able to classify the source of information. 8. In 55 cases (50%) the canoe, mass were discovered incidentally, in 39 cases (35.5%) by manual detection by self, in 10 cases (9%) by others and in 6 cases(5.5%) by observing subjective symptoms. 9. The average duration lapsed between the discovery of cancer mass and the visit to the hospital revealed to be 9.4 month. Chief reason for the delay revealed to be the non-chaplaincy due to the absence of pain(N=50, 45.5 %) followed by the administration of herb and commercial medication (N=19, 17.3%). 10. The left side breast was more affected than the right side breast, represent by 60 cases in the left and 39 cases in the right. The most frequent site of the breast cancer was the upper- outer quadrant in 53 cases (47.7%), and followed by the center in 20 cases(18 %), and the upper inner quadrant, in 19 cases (17.1%). There was / cases of bilateral carcinoma. The most prominent symptom was painless mass.

• Korean Journal of Agricultural Science
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• v.19 no.2
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• pp.153-160
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• 1992

To investigate the potential of paper mill sludge and briquet ash as cultural media in turfgrass, zoysiagrass was grown in the mixtures prepared with paper mill sludge and briquet ash. The mixtures were consisted of sludge and briquet ash in the ratio by volume 3:1, 2:1, 1:1, 1:2, and 1:3 in the order. To compare the growth responses, some plants were grown in the medium containing sand(3), field soil(1) and peatmoss (1) by volume anti regarded as control. 1. Activated sludge mixed with sand increased plant height, fresh weight, and dry weight more than 1.5-2.0 times compared to those of the control. The highest plant growth was shown in mixtures containing 67% activated sludge. 2. Plant density per $100cm^2$ and chlorophyll content were higher in all mixtures containing activated sludge than control. 3. The growth of zoysiagrass was reduced along with the increase of non-activated sludge ratio, but no difference was found in chlorophyll content. 4. Plant height, fresh weight and dry weight were greater in activated sludge combined with sand compared to the briquet ash mixtures, but the difference of shoot density between two mixtures was not shown. 5. Even though non-activated sludge appeared not to be appropriate to the growth of seedlings, the number of tillers of plant propagated with rhizome was more increased compared to control when briquet ash content was less than 75%.

• Journal of Korea Port Economic Association
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• v.28 no.3
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• pp.127-150
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• 2012

A survey showed that the public perception of the shipping industry's overall image and economic role was relatively positive. The survey revealed that public perception was mixed with respect to the multifaceted role of the shipping industry. Based on the results of this survey, this paper proposes three approaches to improving the public perception of the shipping industry. The organization contact approach includes establishing shipping institutes for city people, holding various events targeted at the public, establishing a shipping memorial hall, developing a shipping-related culture and tourism, reinventing the image of the shipping industry through a shipping-culture movement, and creating new views of the shipping industry by conducting formal education. The goods and services contact approach includes building a brand image for shipping services, providing B2C services, utilizing the national image for the shipping industry, and participating in international cooperation projects. The text contact approach includes B2B advertising, advertisements focused on the national economic and multifaceted role of the shipping industry, package advertisements for the shipping industry and related industries, the Internet and high-technology media, government-initiated PR activities regarding the multifaceted role of the shipping industry, and funding for advertising the shipping industry.

• The KIPS Transactions:PartC
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• v.18C no.3
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• pp.167-178
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• 2011

As the growth of ubiquitous services, various types of ad hoc networks have emerged. In particular, wireless sensor networks (WSN) and mobile ad hoc networks (MANET) are widely known ad hoc networks, but there are also other kinds of wireless ad hoc networks in which the characteristics of the aforementioned two network types are mixed together. This paper proposes a variant of the Low Energy Adaptive Cluster Hierarchy (LEACH) routing protocol modified to be suitable in such a combined network environment. That is, the proposed routing protocol provides node detection and route discovery/maintenance in a network with a large number of mobile sensor nodes, while preserving node mobility, network connectivity, and energy efficiency. The proposed routing protocol is implemented with a multi-hop multi-path algorithm, a topology reconfiguration technique using node movement estimation and vibration sensors, and an efficient path selection and data transmission technique for a great many moving nodes. In the experiments, the performance of the proposed protocol is demonstrated by comparing it to the conventional LEACH protocol.

• The Korean Journal of Mycology
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• v.26 no.3 s.86
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• pp.380-386
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• 1998

To obtain basic data for mass production of Isaria japonica, cultural characteristics of japonica were investigated by using liquid, solid media and silkworms pupa. Mycelia grew favorably at the temperature of $23{\sim}28^{\circ}C$ on MYG medium with pH 7.0. The fruiting-body of I. japonica was induced below $20^{\circ}C$ in MYG liquid medium (Malt yeast glucose) under fluorescent light. In MYG basal medium mixed with pupal powder of silkworms, the fresh weight of fruiting-bodies was increased with increasing concentration of pupal powder. The highest yield of fruiting bodies was obtained in carbon-rich medium supplemented with pupal powder of silkworm. Also, fruiting-bodies of I. japonica were produced massively on the silkworm pupa placed on the stainless tray in the shortest time. The structure and shape of fruiting-bodies were coral-like, many-branched types with numerous conidiospores.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.5
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• pp.369-376
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• 2007

This experiment was carried out to investigate optimum conditions of coir-based substrates for the red pepper plug seedlings. Eleven different coir based substrates prepared by mixing of coir, vermiculite, rice hull, perlite, zeolite, mixed at different ratios were tested. The physical and chemical properties of the substrates were analyzed by the CEN (European committee for standardization) method. Fresh and dry weights of shoot and root, leaf area, root length, and T/R ratio (dry shoot weight/dry root weight) were determined at 55 days after sowing. The results showed that the growing media CRZ 8(coir:rice hull: vermiculite=8:1.9:0.1) and CVSZ 6(coir:silver vermiculite: zeolite=6:3.9:0.1) can successfully be used for pepper plug seedlings judging from dry weight and T/R ratio of the plug seedlings. The optimal range of total pore space, water volume, air volume, easily available water content and water buffering capacity of the coir-based growing substrates for pepper plug seedlings were in the range of 92~94%, 52~60%, 32~43%, 18~21%, and 0.9~8%, respectively.

• The Journal of the Korea Contents Association
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• v.19 no.2
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• pp.424-437
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• 2019

The purpose of this study is to analyze the characteristics and stigma of children and adolescents, and the message types for them in NPO's fundraising advertisement videos in Korea. The subjects are 152 children and adolescents in 147 videos from seven major non-profit organizations. The analysis tools were constructed based on prior studies, and it was carried out after preliminary study. The results are as follows. First, the characteristics of children and adolescents indicated that the ratio of children and infants, main-role, poverty situation, one-parent family, and ward-role appeared the most. Second, 'general' was the highest in the stigma format, and 'hazard' and 'mark' was high in the challenge format. Third, the stigma message was the highest in message type. Finally, as of 2014, the ratio of stigma message and value-exclusion message increased, and the ratio of challenge message and mixed message decreased. The research suggests that a paradigm shift in the format of NPO's typical fundraising advertisement videos is necessary, as the videos may not protect the human rights of children and adolescents and may have negative effects such as stigma.