• Journal of IKEEE
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• v.13 no.4
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• pp.23-27
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• 2009

Ohmic contact formation and etching processes for the fabrication of MBE (molecular beam epitaxy) grown GaSb-based p-channel HEMT devices on Si substrate have been studied. Firstly, mesa etching process was established for device isolation, based on both HF-based wet etching and ICP-based dry etching. Ohmic contact process for the source and drain formation was also studied based on Ge/Au/Ni/Au metal stack, which resulted in a contact resistance as low as $0.683\;{\Omega}mm$ with RTA at $320^{\circ}C$ for 60s. Finally, for gate formation of HEMT device, gate recess process was studied based on AZ300 developer and citric acid-based wet etching, in which the latter turned out to have high etching selectivity between GaSb and AlGaSb layers that were used as the cap and the barrier of the device, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5477-5482
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• 2012

Background: The HER-2/neu gene is altered in 15-20% of breast cancer patients. Immunohistochemistry (IHC) is considered to be the most cost-effective method for HER-2 detection in many countries. Approximately 8,000 new cases of breast cancer are observed annually in Iran. The aims of this study were to conduct a systematic review of the literature on the rate of HER-2-positive breast cancer diagnosed by IHC in Iran. Methods: A systematic search of the medical literature using the Medline/PubMed, ISI and SID databases revealed articles published in the English and Persian languages evaluating HER-2-positive breast cancer in Iran. Results: From 22 studies, 3,033 patients were evaluated, of whom 1,350 were diagnosed as HER-2-positive by IHC HER-2 testing. The mean percentage of HER-2-positive patients was 44.5%, which is higher than that recorded in international statistics. Results of this meta-analysis showed a significant heterogeneity between ratios. There was a statistically significant difference between the results of pre- and post implementation of 2007 American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) guideline. IHC HER-2 testing has been performed in Iran for over 10 years. Similar to many other countries, before establishment of an infrastructure for IHC diagnostic tests, HER-2 testing was routinely performed in Iran. Our study showed that the statistics reported from Iran varied widely; for instance, the rate of HER-2-positive cases varied from 23.3% to 81.0%. Conclusions: Our results demonstrate that the lack of standardization and harmonization of this test have led to marked variations in breast cancer diagnosis in Iran.

• Analytical Science and Technology
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• v.27 no.1
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• pp.22-26
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• 2014

1,4-Dioxane was classified as a Group 2B carcinogen by the International Agency for Research on Cancer. The compound was measured in surface water with a headspace gas chromatographic mass spectrometric detection. A 5 mL water sample was placed in a 10 mL headspace vial and saturated with NaCl, and the solution was spiked with 1,4-dioxane-d8 as an internal standard and sealed with a cap. Water samples were collected from twenty-two basins of Gum-River on June and September 2012, respectively. As a result, 1,4-dioxane was detected in the concentration range of $0.49-43.0{\mu}g/L$ (mean $2.0{\mu}g/L$) in the frequency of about 30% in surface water samples.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.1
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• pp.50-55
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• 2020

Porcelain insulators have been used for a long time in 154 kV power transmission lines. They are likely to be exposed to sudden failure because of product deterioration. This study was conducted to evaluate the quality of porcelain insulators. After stresses were applied, the damaged regions of aged insulators were investigated in terms of chemical composition, material structure, and other properties. For porcelain insulators that were in service for a long time, the mechanical failure load was 126 kN, whereas the average mechanical failure load was 167.3 kN for new products. It was also determined that corrosion occurred at the metal pin part due to the penetration of moisture into the gap between the pin and the ceramic. Statistical analyses of failure were performed to identify the portion of the insulators that were broken. Cristobalite porcelain insulators fabricated without alumina additives had a high failure rate of 54% for the porcelain component. In the case of the addition of Alumina (Al₂O₃) to the porcelain insulators to improve the strength of the ceramic component, a more frequent damage rate of the cap and pin of 73.3% and 27%, respectively, was observed. This study reports on the material component of SiO₂ and the percentage of alumina added, with respect to the mechanical properties of porcelain insulators.

• Journal of the Korean Geosynthetics Society
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• v.18 no.4
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• pp.193-204
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• 2019

Reliability analyses of sixteen domestic design cases of open cell caisson breakwaters against circular sliding failure were conducted in this study. For the reliability analyses, uncertainties of parameters of soils, mound, and concrete cap were assessed. Bishop simplified method was used to obtain load and resistance of open cell caisson breakwater for randomly generated open cell caisson breakwater. Sufficient number of Monte Carlo simulations were conducted for randomly generated open cell caisson breakwaters, and statistical analysis was conducted on loads and resistances collected from the large number of Monte Carlo simulations. Probability of failure produced from Monte Carlo simulation has a nonconvergence issue for very low probability of failure; therefore, First-Order Reliability Method (FORM) was conducted using the statistical characteristics of loads and resistances of open cell caisson breakwaters. In addition, effects of safety factor, uncertainties of load and resistance, and correlation between load and resistance on reliability of open cell caisson breakwaters against circular sliding failure were examined.

• Journal of the Korean Geosynthetics Society
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• v.18 no.4
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• pp.205-214
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• 2019

Load and resistance factor design of mound breakwater against circular failure was developed in this study. To achieve the goal, uncertainties of parameters of soils, mound, and concrete cap were determined. Eight design cases of domestic mound breakwaters were collected and analyzed. Monte Carlo Simulation was implemented to determine the most critical slip surfaces of the design cases. Using the results of Monte Carlo Simulation, First-Order Reliability Method (FORM) was used to perform reliability analyses. Optimal load and resistance factors were calculated using the reliability analysis results and final load and resistance factors were proposed based on the calculated optimal factors.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.3 no.2
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• pp.142-151
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• 1991

In the present investigation, it has been proposed to utilize a direct contact heat exchanger as an evaporator to solve the difficulties such as scaling, corrosion and law thermal efficiencies, associated with the conventional evaporator. Liquified nitrozen was utilized as a working fluid to investigate basic natures of bubble dynamics in the evaporator, and spray nozzles were adopted to inject liquified nitrozen into the spray column with varying flow rates of dispersed phase fluids. Experimentations were carried out in the range of $6.54{\times}10^{-4}kg/s$ - 0.030 kg/s for dispersed phase flow rates with one, three and five nozzle holes. Observing the bubble dynamics for the evaporator the feasibility of utilizing a direct contact heat exchanger as a LNG evaporator has been evaluated. The results show that no eruption phenomena was observed in the present investigation with $LN_2$ and the interface between $N_2$ bubbles and water was fully turbulent. It is believed that the high injection velocity of $LN_2$ through the spray nozzles provide good mixing effects for both heat and mass transfers between water and $N_2$ bubbles. Ice was formed on the surface of the spray nozzle for higher $LN_2$ flow rates. However, even in this case, it is observed that the ice was detached as soon as it was formed. Under the present experimental conditions, the shapes of $LN_2$ bubbles were in the spherical-cap region according to the Clift, Grace and Weber Graphs. The height of foam region caused by the breakup of larger bubbles keeps increasing with high injection velocities until it reaches it's maximum height.

• The Journal of Internal Korean Medicine
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• v.36 no.3
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• pp.297-307
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• 2015

Objectives: We aimed to evaluate the effect of Cervi Cornu and coenzymeQ10 on exercise and endurance capacity in rats and mice. Methods: The extract of Cervi Cornu was manufactured by the pharmacy department of Kyung Hee Oriental Medical Hospital, and CoQ10 soft cap (Ildong Pharmaceutical) was used. In total, 24 rats and 30 mice were divided into 3 groups: Control (rat=8, mouse=10), CoQ10 alone (rat=8, mouse=10), Cervi Cornu extract, and CoQ10 (rat=8, mouse=10). Ergogenic effect was evaluated by administering the Cervi Cornu extract and coenzymeQ10 to rats and measuring the time to exhaustion during treadmill running; endurance capacity was assessed by measuring cold water swimming time, serum lactate level, and serum corticosterone level in each group. At 1 week from the end of treatment, we recalculated time to exhaustion during treadmill running in rats to investigate the long-term effect of the Cervi Cornu extract and coenzymeQ10. Results: Cervi Cornu extract has long-term benefits in that it preserves the ergogenic effect caused by exercise. Cervi Cornu and coenzymeQ10 have no effect on increasing cold water swimming time in ICR mice. CoenzymeQ10 decreases the serum corticosterone level in ICR mice performing cold water swimming test. Conclusions: Cervi Cornu seems to preserve the ergogenic effect caused by exercise, but a larger study is needed to investigate effect of Cervi Cornu and coenzymeQ10 on improving endurance capacity. CoenzymeQ10 decreases serum corticosterone level and it is related with the anti-psychological fatigue effect.

• Journal of Environmental Policy
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• v.14 no.2
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• pp.101-131
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• 2015

A cap-and-trade program accounting for 60 percent of total national greenhouse gas emissions was launched in South Korea in 2015. Academic literature expects that the implementation of such a policy is likely to adversely impact income distribution among various socioeconomic groups in developed countries. South Korea is challenged by equity issues, as well circumstances, the distributional implications of carbon pricing policies need to be examined and reflected in the design of the program prior to implementation in order not to exacerbate social inequity. Using environmentally extended input-output analysis together with household expenditure data, this study finds that a carbon pricing policy will be regressive in South Korea, but the extent depends on whether relative burdens of a carbon pricing policy are measured based on current incomes or proxies of permanent incomes. Along with poor households, this paper finds that elderly and urban households will be more adversely impacted in South Korea. These burdens can be relieved if a small fraction of the revenue is redistributed to households.

• Korean Journal of Community Nutrition
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• v.10 no.3
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• pp.264-270
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• 2005

Breastfeeding has been known as the best feeding practice to prevent allergies including atopic dermatitis (AD) However, the benefit on the prevention of allergic disease is still controversial. The objectives of this study were to examine the rate of sensitization to the protein of eggs, cow's milk and soy in exclusively breastfed infants and to evaluate antigen-antibody reaction between breast milk and serum of AD infant. Data on feeding and food hypersensitivity were obtained for 62 AD infants (32 male, 30 female) aged < 6 month who had visited Samsung Medical Center from September 2001 to May 2003. Food hypersensitivity was determined by measuring specific IgE to egg, cow's milk and soy. Specific IgE levels > 0.7 kU/L by CAP assay (Pharmacia, Uppsala, Sweden) were considered positive. The rates of sensitization in breastfed infants were $41.9\%$ (26/62) to egg, $30.6\%$ (19/62) to milk and $18.0\%$ (11/62) to soy. Immunoblotting analyses were performed using breast milk with the matched serum of seven AD infants (4 male/3 female). Binding patterns of AD infant's IgE to breast milk extract showed visible specific band for immunoglobulin, especially in case of a lactating mother who did not completely restricted ingestion of egg, milk and soy. These results indicate that sensitization to food allergen develops via breast milk feeding. Breast milk feeding should be recommended in infants at risk of developing allergic disease, but maternal intake of highly allergenic food might be restricted for prevention and treatment of food allergy among the babies with AD.