• Journal of the Korean Electrochemical Society
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• v.4 no.2
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• pp.58-64
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• 2001

YSZ ($8mol\%$ yttria-stabilized zirconia)-modified LSM $(La_{0.85}Sr_{0.15}MnO_3)$ composite cathodes were fabricated by formation of YSZ film on triple phase boundary (TPB) of LSM/YSZ/gas. The YSZ coating film greatly enlarged electrochemical reaction sites from the increase of additional TPB. The composite cathode was formed on thin YSZ electrolyte (about 30 Um thickness) supported on an anode and then I-V characterization and AC impedance analyses were performed at temperature between $700^{\circ}C\;and\;800^{\circ}C$. As results of the impedance analysis on the cell at $800^{\circ}C$ with humidified hydrogen as the fuel and air as the oxidant, R1 around the frequency of 1000 Hz represents the anode Polarization. R2 around the frequency of 100Hz indicates the cathode polarization, and R3 below the frequency of 10 Hz is the resistance of gas phase diffusion through the anode. The cell with the composite cathode produced power density of $0.55\;W/cm^2\;and\;1W/cm^2$ at air and oxygen atmosphere, respectively. The I-V curve could be divided into two parts showing distinctive behavior. At low current density region (part I) the performance decreased steeply and at high current density region (part II) the performance decreased gradually. At the part I the performance decrease was especially resulted from the large cathode polarization, while at the part H the performance decrease related to the electrolyte polarization.

• Korean Journal of Food Science and Technology
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• v.45 no.6
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• pp.682-692
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• 2013

We investigated out the effect of cultivation region on the physicochemical characteristics of starch in six sweetpotato cultivars. The following sweetpotato cultivars were analyzed: Daeyumi, Shingeonmi, Jinhongmi, Shinyulmi, Yulmi, and Yeonhwangmi. Samples were cultivated in Muan, Iksan, Nonsan, Boryeong and Hamyang. The soil texture was found to be sandy loam in Muan, Iksan, and Boryeong, sandy clay loam in Nonsan, and loam in Hamyang. The starch content of the sweetpotato was higher in Muan than in Hamyang. The amylose content was 22.3-30.9%, and the highest amylose content was found in samples from Iksan. Rapid viscosity analysis showed that the samples from Hamyang had the lowest values of pasting temperature, while samples of the Daeyumi cultivar had the highest values. Thermal analysis with a differential scanning calorimeter showed that the Muan samples had the highest values of onset temperature, maximum peak temperature, and completion temperature, and the samples from Hamyang had the lowest values. There was no difference between the cultivation regions or the cultivar in the X-ray pattern of the starch or its appearance in scanning electron micrographs. Therefore, the results of this study confirm that cultivation region and cultivar play an important role in determining the quality of sweetpotato and the physicochemical characteristics of sweetpotato starch.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1995.06b
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• pp.77-96
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• 1995

To obtain basic informations for the improvement of seed potato production in Korea, some etiological properties of potato virus Y(PVY) distributed in the major seed potato production area(Daekwanryeong) were characterized, and the nucleotide and amino acid sequences of the coat protein gene of the PVY strains isolated were analyzed. PVY strains in Daekwonryeong, an alpine area, were identified to be two strains, PVYo and PVYN by symptoms of indicator plants, and their distribution in potato fields was similar. Major symptom on potato varieties by PVY was grouped as either mosaic alone or mosaic accompanied with veinal necrosis in the lower leaves. The symptom occurrence of the two symptoms was similar with Irish Cobbler, but Superior showed a higher rate of mosaic symptom than the other. The PVY strain which was isolated from potato cv. Superior showing typical mosaic symptoms produced symptoms of PVY-O on the indicator plants of Chenopodium amaranticolor, Nicotiana tabacum cv. Xanthi nc and Physalis floridana, but no symptom o Capsicum annum cv. Ace. Moreover, results from the enzyme-linked immunosorbent assay with monoclonal and polyclonal antibodies showed that the isolated PVY reacts strongly with PYV-O antibodies but does not react specifically with PVY-T antibodies. The purified virus particles were flexious with a size of 730$\times$11nm. On the basis of the above characteristics, the strain was identified to be a PVY-O and named as of PVY-K strain. The flight of vector aphids was observed in late May, however, the first occurrence of infected plants was in mid June with the bait plants surrounded with PVY-infected potato plants and early July with the bait plants surrounded with PVY-free potato plants. PVY infection rates by counting symptoms on bait plants (White Burley) were 1.1% with the field surrounded with PVY-free potato plants and 13.7% the fields surrounded with PVY-infected potato plants, showing the effect of infection pressure. The propagated PVY-K strain on tobacco(N. sylvestris) was purified, and the RNA of the virus was extracted by the method of phenol extraction. The size of PVY-K RNA was measured to be 9, 500 nucleotides on agarose gel electrophoresis. The double-stranded cDNAs of PVY-K coat protein(CP) gene derived by the method of polymerase chain reaction were transformed into the competent cells of E. coli JM 109, and 2 clones(pYK6 and pYK17) among 11 clones were confirmed to contain the full-length cDNA. Purified plasmids from pYK17 were cut with Sph I and Xba I were deleted with exonuclease III and were used for sequencing analysis. The PVY-K CP gene was comprised of 801 nucleotides when counted from the clevage site of CAG(Gln)-GCA(Ala) to the stop codon of TGA and encoded 267 amino acids. The molecular weight of the encoded polypeptides was calculated to be 34, 630 daltons. The base composition of the CP gene was 33.3% of adenine, 25.2% of guanine, 20.1% of cytosine and 21.4% of uracil. The polypeptide encoded by PVY-K CP gene was comprised of 22 alanines, 20 threonines, 19 glutamic acids and 18 glycines in order. The homology of nucleotide sequence of PVY-K CP gene with those of PVY-O(Japan), PVY-T(Japan), PVY-TH(Japan), PVYN(the Netherlands), and PVYN(France) was represented as 97.3%, 88.9%, 89.3%, 89.6% and 98.5%, respectively. The amino acid sequence homology of the polypeptide encoded by PVY-K CP gene with those encoded by viruses was represented as 97.4%, 92.5%, 92.9%, 92.9%, and 98.5%, respectively.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.4
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• pp.205-210
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• 2006

Purpose: FDG uptake on positron omission tomography (PET) has been considered a prognostic indicator in non-small cell lung cancer (NSCLC). The aim of this study was to assess the clinical significance of maximum value of SUV (maxSUV) in recurrence prediction in patients with surgically resected NSCLC. Materials & methods: NSCLC patients (n=42, F:M =14:28, age $62.3{\pm}12.3$ y) who underwent curative resection after FDG-PET were enrolled. Twenty-nine patients had pathologic stage 1, and 13 had pathologic stage II. Thirty-one patients were additionally treated with adjuvant oral chemotherapy. MaxSUVs of primary tumors were analyzed for correlation with tumor recurrence and compared with pathologic or clinical prognostic indicators. The median follow-up duration was 16 mo (range, 3-26 mo). Results: Ten (23.8%) of the 42 patients experienced recurrence during a median follow-up of 7.5 mo (range, 3-13 mo). Univariate analysis revealed that disease-free survival (DFS) was significantly correlated with maxSUV (<7 vs. $\geq7$, p=0.006), tumor size (<3 cm vs. $\geq3$ cm, p=0.024), and tumor tell differentiation (well/moderate vs. poor, p=0.044). However, multivariate Cox proportional analysis identified maxSUV as the single determinant for DFS (p=0.014). Patients with a maxSUV of $\geq7$(n=10) had a significantly lower 1-year DFS rate (50.0%) than those with a maxSUV of <7 (n=32, 87.5%). Conclusion: MaxSUV is a significant independent predictor for recurrence in surgically resected NSCLC. FDG uptake can be added to other well-known factors in prognosis prediction of NSCLC.

• Journal of radiological science and technology
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• v.33 no.1
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• pp.19-24
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• 2010

The aim of this study was to evaluate the change of bone mineral density according to distal radius rotation and the correlations of the lowest BMD measured by DXA at the lumba versus distal radius. The eleven males were projected distal radius by DR X-ray and the measurement of BMD by DXA of the appropriate position of the forearm were performed on 21 males. The healthy 11 and 21 volunteers without any history of operations, anomalies, or trauma were enrolled. The experiment was performed by two methods. First, The DR X-ray was measured distal radius of 11 males in pronation and supination with three, six and nine degrees, including a neutral position. The ROI was measured by the m-view program on the PACS monitor. Second, The DXA was measured distal radius of 21 males in pronation and supination with five and ten degrees, including a neutral position to evaluate the changes of BMD according to the rotation. A correlation of the BMD in the distal radius with BMD that lumbar spine was performed, along with analysis of the data by SPSS 12.0v. The mean rotation angle of the distal radius about eleven males DR X-ray measured $7^{\circ}$ of pronation (82%, n = 9), $6^{\circ}$ of supination and $0^{\circ}$ of neutral of (9%, n = 1), The total average rotation angle in 11 male was $5.1^{\circ}$ of pronation. The rotation angle of the distal radius about twenty one males on DXA measured $7.2^{\circ}$ of pronation (43%, n = 9), $7^{\circ}$ of supination (24%, n = 5), and $0^{\circ}$ of neutral (33%, n = 7), The total average rotation angle in 21 people was $4.1^{\circ}$ of pronation. The correlation of the analysis of lumba and distal radius were r = 3.0, p = 0.18. consequently, The correlation was not significance. Because BMD of lumba was not coverd for BMD of the distal radius, with a neutral position, Pronation is needed for BMD in the distal radius with the rotation angle measuring at the lowest BMD. the rotation angle about five degrees of pronation of the distal radius is recommended.

• Journal of Korean Society of Transportation
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• v.25 no.5
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• pp.125-133
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• 2007

Through open-sky policy, USA and European selected market principle of multiuser. However, in Asian case, major airlines monopolize airports. It is purpose that analyzes fare competition of Asian Hub Airport and the position of Incheon airport in Asia. Passengers required longer time and distance to go to the destination because direct flights decreases. But passengers increased in airport every year. Because of routes that decrease, airlines provide more services of flights. So airlines prefer to Hub Airports. As a result, both passengers and airlines are profitable by various routs and the increased frequency. On the assumption that distance and fare are related, the final formula is as following that defined the air fare from hub(H) to destination(Z) by logarithm. Analysis showed that log Rdist is not 1 but 0.08. As distance increases, fare doesn't increase. If distance from hub to destination airports is longer, Log dist_HZ is negative. It is that fare decreases from origin to destination via hub or that fare increases from hub to destination. HHI_HZ and HHI_AZ are negative. It means that if the degree of monopolization of hub and origin airports is lager, fare decreases from origin to destination via hub. Or fare increases from hub to destination. And it compares the Incheon airport with the other Asian hub airports and it examines the competitive fare by market division. As compared with the Incheon airport, Singapore, Beijing and Narita airports are higher fares. They compete with the other ones by Asian hub airports. But Hong Kong and Taipei airports must have more passengers through fare competition yet.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.1
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• pp.62-72
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• 2007

The purpose of present study was to determine whether different kinds of curing lights can alter microtensile bond strength(MTBS) of class I cavity pulpal and axial wall specimens in primary molar. Thirty clean mandibular 2nd primary molar's occlusal enamel were removed and class I cavity, size of $2{\times}4{\times}2mm$ was prepared. Dentin bonding agent was applied according to manufacturer's manual. Each group was cured with Halogen Curing Unit, Plasma Curing Unit and LED Curing Unit. Composite resin was bulk filled and photo cured with same curing unit. MTBS specimens which size is $0.7{\times}0.7{\times}4mm$ were prepared with low speed saw. Specimens were coded by their curing lights and wall positions (Halogen - Axial wall group, Halogen - Pulpal wall group, Plasma - Axial wall group, Plasma - Pulpal wall group, LED - Axial wall group, LED - Pulpal walt group). MTBS were tested at 1 mm/min cross Head speed by Universal Testing Machine. Fractured surface and bonding surface was observed with SEM. T-test between axial and pulpal specimens in each curing lights, one-way ANOVA among different curing light specimens in each wall positions were done. Weibull distribution analysis was done. The results were as follows : Mean MTBS of pulpal wall specimens were significantly greater than that of axial wall specimens at each curing units(p<.05). There was no significant difference in the MTBS among three curing units at axial wall and pulpal wall. In Weibull distribution, pulpal wall specimens were more homogeneous than axial wall specimens.

• Tuberculosis and Respiratory Diseases
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• v.53 no.3
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• pp.309-318
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• 2002

Background : Usual interstitial pneumonia (UIP) is a fatal progressive fibrotic disorder of the lung with unknown etiology and characterized by a poor response to conventional immunosuppressive therapy. The histologic hallmark of UIP is parchy distribution of subpleural fibrosis and fibroblastic foci(FBF) with interposed normal appearing lung. Because FBF is a collection of actively proliferating myofibroblasts, it can be a marker of activity and prognosis of UIP. However, there were contradictory reports about the correlation between the degree of FBF and survival. Therefore we performed this study to investigate the value of FBF as prognostic marker of UIP. Methods : This was a retrospective study on the 46 patients(M:F=33:13, mean age:$59{\pm}12$ years) with UIP diagnosed by the surgical lung biopsy at the Asan Medical Center, Seoul, Korea between 1990 and 2000 and had follow-up of more than a year. All the biopsy specimens were reevaluated and diagnosed as UIP according to the ATS/ERS classification. Semiquantitative grading of FBF(absent, 0; mild 1; moderate 2; marked 3) by the experienced pathologists who did not know the clinical findings were compared to the clinical data and the follow up course. Results : Thirteen patients(28.2%) died of UIP progression during the study period. The median survival time of all the subjects was 26 months after the biopsy. At the univariate analysis, FVC, $D_Lco$, smoking history and the grade of FBF were significantly related to the survial. The survival was longer in subjects with lesser degrees of FBF, higher DLco, higher FVC and history of smoking. However the multivariate analysis with Cox regression test showed the extent of FBF was the only independent prognostic marker of UIP. Conclusion : These data suggested that the extent of FBF on the surgical lung biopsy can be used as a prognostic marker of UIP.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.4
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• pp.1-14
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• 2017

In Korea, the soil series derived from sedimentary rocks are classified into seven soil series of coarse loamy soil such as Dain, Danbug, Dongam, Imdong, Jeomgog, Maryeong, and Yonggog; seventeen soil series of fine loamy soil such as Angye, Anmi, Banho, Bigog, Deoggog, Dogye, Dojeon, Gamgog, Gugog, Jincheon, Maji, Mungyeong, Oggye, Samam, Yanggog, Yeongwol, and Yulgog; six soil series of fine silty soil such as Goryeong, Bonggog, Juggog, Gyeongsan, Yuga, and Yugog; and four soil series of clayey soil such as Mitan, Pyeongan, Pyeongjeon, and Uji. All thirty-four soil series have different drainage rates and topography. However, the soil texture depends on the parent rock. The buffer functions in GIS (Geographic Information System) techniques were used to calculate adjacent soil series from a soil series. The length of the adjacent soil series was adjusted because a side of the buffer area was one meter long. The cluster analysis was conducted using the CCC (Cubic Clustering Criterion) method, in which the number of clusters is calculated based on the individual soil series ratio. Soil survey has been carried out since 1964 as "The reconnaissance soil survey", and 1:5,000 detailed soil survey was completed in 1999 with a five-years plan in Korea. Today, all the soil survey information has been computerized. GIS techniques were used to establish a digital soil map; however, there have not been any studies to interpret pedogenesis using the GIS technique. In this study, the area of the adjacent soil series were obtained using the GIS technique. The area of the adjacent soil series can be calculated based on the information area. The similarities of soil originated from sedimentary rocks were estimated using the length. As a result, the distribution of grain size was different based on the types of sedimentary rocks and the location. The clusters were distinguished into limestone, sandstone, and shale. In addition, the soil derived from shale was divided into red shale and gray shale. This means that quantitative interpretation of the catena and this established method can be used to interpret the relationship between soil series.

• Korean Journal of Environment and Ecology
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• v.15 no.4
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• pp.361-368
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• 2002

The valley forests located at the east-facing slope and the west facing slope in Hambaeksan area were studied to investigate forest structure in relation to aspect and altitude of the slope. There was little difference in density. mean DBH and basal area of the tree layer between east-facing slope and west-facing slope. The importance percentages of Tilia amurensis and Betula costata in west-facing slope were higher than those in east-facing slope. However, the importance percentages of Quercus mongilica and Fraxinus rhynchophylla in the west facing slope were lower than those in east-facing slope. Species diversity of the west-facing slope was 1.415 and that of the east-facing slope was 1.328. Elevation trends were also found for forest structure. As elevation Increased basal area and mean height of the tree layer decreased in both of east-facing slope and west-facing slope. There was a tendency that number of species, species diversity and evenness decreased with increasing elevation. The importance percentage of Quercus mongolica increased with increasing elevation while those of Betula costata and Maackia amurensis decreased. The result of cluster analysis for the tree and subtree layer indicated that the studied forests were classified into the mixed forest community of broad-leaved tree species at west-facing slope and the low and middle elevation belts of east-facing slope and Quercus mongolica community at the high elevation belt of east-facing slope. Quercus mongolica was significantly and positively correlated with Symplocos chinensis for. pilosa, Acer tschonoskii var. rubripes and deutzia glabrata. Betula costata was significantly and negatively correlated with Quercus mongolica and Acer pseudo-sieboldianum.