• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.520-527
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• 2006

A realistic surface model is presented for prediction of various surface phenomena such as polymer deposition, suppression and sputtering as a function of incidence ion energy in high density fluorocarbon plasmas. This model followed ion enhanced etching model using the "well-mixed" or continuous stirred tank reactor (CSTR) assumption to the surface reaction zone. In this work, we suggested ion enhanced polymer formation and decomposition mechanisms that can capture $SiO_2$ etching through a steady-state polymer film on $SiO_2$ under the suppression regime. These mechanisms were derived based on experimental data and molecular dynamic simulation results from literatures. The model coefficients are obtained from fits to available beam and plasma experimental data. In order to show validity of our model, we compared the model results to high density fluorocarbon plasma etching data.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4549-4552
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• 2013

The incidence of gastric cancer worldwide, and in particular in developing countries, has shown a marked increase. Poor prognosis of gastric cancer patients occurs due to the rapid metastasis of the disease via the lymphatic and blood vessels. The aim of this study was to investigate the expression and the clinical significance of D2-40 and CD34 in human gastric cancer. D2-40 and CD34 expression wasdetected in 1,072 cases of Chinese patients with gastric carcinoma using immunohistochemistry. The lymphatic vessel density (LVD) and microvessel density (MVD) were calculated and analyzed and the correlation with the clinicopathological factors and prognosis was determined. The LVD and MVD of the gastric cancer cases were significantly higher compared to those of normal tissues (P < 0.05). The expression of D2-40-LVD and CD34-MVD in the malignancies were positively related to the age, tumor size, invasion depth, lymphatic metastasis and pathological tumor-node-metastasis (pTNM) (P < 0.05); However, no statistically significant difference was identified between them with the patient gender (P > 0.05). Up-regulation of D2-40 and CD34 expression was significantly correlated with the poor survival rate in univariate and multivariate analyses. The LVD marked by D2-40 and the MVD marked by CD34 were positively correlated to the clinicopathological factors of the malignancies and may play important role in the development and progression of gastric cancer.

• Journal of Preventive Medicine and Public Health
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• v.53 no.5
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• pp.342-352
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• 2020

Objectives: The aim of this retrospective cohort study was to investigate whether non-alcoholic fatty liver disease (NAFLD) was associated with incident bone mineral density (BMD) decrease. Methods: This study included 4536 subjects with normal BMD at baseline. NAFLD was defined as the presence of fatty liver on abdominal ultrasonography without significant alcohol consumption or other causes. Decreased BMD was defined as a diagnosis of osteopenia, osteoporosis, or BMD below the expected range for the patient's age based on dual-energy X-ray absorptiometry. Cox proportional hazards models were used to estimate the hazard ratio of incident BMD decrease in subjects with or without NAFLD. Subgroup analyses were conducted according to the relevant factors. Results: Across 13 354 person-years of total follow-up, decreased BMD was observed in 606 subjects, corresponding to an incidence of 45.4 cases per 1000 person-years (median follow-up duration, 2.1 years). In the model adjusted for age and sex, the hazard ratio was 0.65 (95% confidence interval, 0.51 to 0.82), and statistical significance disappeared after adjustment for body mass index (BMI) and cardiometabolic factors. In the subgroup analyses, NAFLD was associated with a lower risk of incident BMD decrease in females even after adjustment for confounders. The direction of the effect of NAFLD on the risk of BMD decrease changed depending on BMI category and body fat percentage, although the impact was statistically insignificant. Conclusions: NAFLD had a significant protective effect on BMD in females. However, the effects may vary depending on BMI category or body fat percentage.

• Korean Journal Plant Pathology
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• v.10 no.1
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• pp.54-60
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• 1994

Incidence of Rhizoctonia blight ranged from 22.2% to 100% in the golf courses at six geographical locations in Korea from 1989 to 1993. Rhizoctonia blight occurred more severly in southern area than in northern area. Fifty seven isolates of Rhizoctonia solani obtained from diseased parts of zoysiagrasses were grouped to AG2-2 by anastomosis test. Pathogenicity testes revealed that this pathogen was strongly pathogenic to Korean lawngrasses(Zoysia japonica, Z. matrella, Z. tenuifolia), but not pathogenic to creeping bentgrass(Agrostis palustris), bermuldagrass(Cynodon dactylon), Kentucky bluegrass(Poa pratensis), perennial ryegrass(Lolium prenne), and creeping red fescue(Festuca rubra subsp. rubra L.). The isolation frequency of R. solani AG2-2 fro sheaths of the infected plants was the highest by 91.67%, and that from stolons and roots was 11.13% and 5.63% respectively. The pathogen was not isolated from the leaves. Population density of R. solani in the lawn of large circular patch was highest on surface soils down to 1 cm deep with the value of 4.9$\times$104 (CFU/g soil), but below 1 cm population density decreased sharply down to 0.8~9.8$\times$103 (CFU/g soil). Horizontal distribution of propagules in turfgrass soil was higher in the margin than in center of patch, where the number of propagules was similar to these of healthy looking soils close to the margin of diseased patch. The meteorological factors influencing the outbreak of the disease were temperature, the number of rainy days and precipitation. Optimum temperature for disease development of Rhizoctonia blight in field was 20~22$^{\circ}C$, and that for hyphal growth of R. solani AG2-2 in vitro was 25~3$0^{\circ}C$. In Pusan area, Rhizoctonia blight first occurred in late April and rapidly developed in late June. The disease slightly decreased during July to August and developed again in late September in 1993. The monthly disease progress in Pusan area was similar to that in Kyeonggi province.

• Journal of fish pathology
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• v.6 no.2
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• pp.219-231
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• 1993

The author introduces the preventive and therapeutic methods of diseases in Japanese flounder which have been conducted by the Fish Disease Laboratory, the Mikamewan Fishery Cooperative Union, Ehime Prefecture, since 1982. Prevention 1. Addition of a sand substrate in the culture pond was effective to prevent ulcer disease. 2. Bathing in 0.5ppm of copper ion was effective to prevent some parasites. 3. Low stocking density of the fish reduced an incidence of edwardsiellosis or gliding bacterial disease. 4. Removal of the diseased fish prevented thd spread of lyphoeystis. 5. So-called $\pi$-water was effective to prevent the fry from some diseases. 6. Immersion of the juvenile in a sodium nifrusylate solution during transportation was effective to prevent gliding bacterial disease. Therapy 1. Sodium nifrustylate or oxytetracycline was effective to cure gliding bacterial disease. 2. Bathing in formalin(150ppm) or freshwater was effective to cure scuticociliatidosis. 3. Erythromycin was effective to cure $\beta$-hemolytic Streptococcus sp. infection. 4. Bathing in a hydrogen peroxide solution(1.5%) was effective to cure white spot disease.

• Journal of Plant Biotechnology
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• v.37 no.3
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• pp.269-274
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• 2010

As the capture fishing industry has declined, the aquaculture industry has become an important source of seafood. With this tendency all fish farming will be performed by large-scale farms where the fish are cultivated in much high density and as a result the incidence of infectious diseases increases. Therefore, vaccination has become an increasingly important part of aquaculture as a cost effective method of controlling various diseases. The early fish vaccines were the formalin inactivated bacteria or virus cultures, which were administered by either immersion or injection. Recombinant DNA biotechnology allowed us to develop orally administrated DNA and recombinant vaccines. In terms of the manufacturing process and cost, Lemna and Spirodela is the most efficient and reliable plant expression system for the production of edible vaccine.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.5-6
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• 2006

There are typically applied on both rear and front sides of electrical contacts to the solar cell. The front contact formation is particularly sensitive to many parameters. Accordingly patterning of front grid line is an important factor of solar cells. This paper describe the electrical conversion efficiency, inclusive of shading loss that gives various spacing between front metal grid lines. In experiments with variation of spacing. It was verified that the wide spacing of grid fingers could increase the series resistance, also the narrow spacing of grid fingers also implies a grid with a higher density of grid fingers. The sunlight of incidence was more of reflection by grid fingers. In result, the short circuit current, which contribute to conversion efficiency was decreased, because maximum power input was reduced and increase the series resistance.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.2
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• pp.60-66
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• 1994

The scattering problem by E-polarized plane wave with oblique incidence on a tapered resistive strip grating with infinite resistivity at strip-edges is analyzed by the method of moments in the spectral domain. Then the induced surface current density is expanded in a series of Ultraspherical polynomials of the zeroth order. The expansion coefficients are calculated numerically in the spectral domain, the numerical results of the geometricoptical reflection coefficient for the tapered resistivity in this paper are compared with those for the existing uniform resistivity. And the position of sharp variation points in the magnitude of the geometric-optical reflection coefficient can be moved by varying the incident angle and the strip spacing. It is found out that these sharp variation points are due to the transition of higher modes between the propagation mode and the evanescent mode.

• Journal of Korea Society of Industrial Information Systems
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• v.8 no.2
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• pp.1-6
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• 2003

A theoretical method for the TE polarized electromagnetic scattering on a periodic strip grating over a grounded dielectric slab is considered. The numerical results for an analysis of the plane wave scattering from the structure are presented such as normalized mode amplitude and relative reflected power against normalized dielectric slab height, relative reflected power against angle of incidence and distribution of strip current density. Detailed discussions on the Bragg blazing phenomena observed in the geometry are give.

• Earthquakes and Structures
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• v.9 no.5
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• pp.1115-1132
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• 2015

The study considers earthquake shake table testing of bending-torsion coupled structures under multi-component stationary random earthquake excitations. An experimental procedure to arrive at the optimal excitation cross-power spectral density (psd) functions which maximize/minimize the steady state variance of a chosen response variable is proposed. These optimal functions are shown to be derivable in terms of a set of system frequency response functions which could be measured experimentally without necessitating an idealized mathematical model to be postulated for the structure under study. The relationship between these optimized cross-psd functions to the most favourable/least favourable angle of incidence of seismic waves on the structure is noted. The optimal functions are also shown to be system dependent, mathematically the sharpest, and correspond to neither fully correlated motions nor independent motions. The proposed experimental procedure is demonstrated through shake table studies on two laboratory scale building frame models.