• Journal of the Korean Chemical Society
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• v.29 no.1
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• pp.52-60
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• 1985

Oxides of nitrogen (NO$_x$) in exhaust gases was determined by absorbing the gas in alkaline peroxide solution containing 0.03${\%}$ H2O2 and 0.1N NaOH. About 100 ppm of NO$_x$ was rapidly oxidized to NO$_2$ or N$_2$O$_5$ by H$_2$O$_2$ and required a contact time of 2 minutes with the absorbing solution for complete absorption. With vigorous shaking including air or oxygen gas, high concentration of NO$_x$ (>200 ppm) can be absorbed within 30 minutes. The remaining H$_2$O$_2$ affect the absorbance of color solution strongly. However, the excess H$_2$O$_2$ was completely decomposed by zinc powder 0.5g and the sample solution should be adjusted to the pH range 6.1∼6.6 before the reduction so that conversion of nitrate to nitrite ion is possible. The absorbed NO$_x$ is determined colorimetrically by the diazotization-coupling method with sulfonilamide and NEDA as the coupling agent. The sensitivity of the new method was 4.48 ${\times}$ 10$^4$ as molar absorptivity which was high sensitive compared with that obtained for the usual zinc reduction NEDA method with O$_3$. This method was far more rapid, brief and accurate than previously published O$_3$-NEDA method in Korean industrial standard.

• Journal of Electrical Engineering and Technology
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• v.11 no.6
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• pp.1610-1613
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• 2016

An analytical method for harmonic estimation of magnetization currents has been developed. The method is based on the results of the waveforms qualitative analysis. The calculation and the experimental results are compared. A good matching is observed.

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1877-1880
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• 2009

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.489-492
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• 2009

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.3 s.345
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• pp.48-58
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• 2006

This paper presents 8x8 two dimensional DCT/IDCT processor of adder-based distributed arithmetic architecture without applying ROM units in conventional memories. To reduce hardware cost in the coefficient matrix of DCT and IDCT, an odd part of the coefficient matrix was shared. The proposed architecture uses only 29 adders to compute coefficient operation in the 2-D DCT/IDCT processor, while 1-D DCT processor consists of 18 adders to compute coefficient operation. This architecture reduced 48.6% more than the number of adders in 8x8 1-D DCT NEDA architecture. Also, this paper proposed a form of new transpose network which is different from the conventional transpose memory block. The proposed transpose network block uses 64 registers with reduction of 18% more than the number of transistors in conventional memory architecture. Also, to improve throughput, eight input data receive eight pixels in every clock cycle and accordingly eight pixels are produced at the outputs.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8229-8237
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• 2014

Background: Organized cervical screening has decreased the incidence of cervical cancer. However, screening strategies vary in different countries. Objectives: We performed a systematic review to evaluate the economic aspects of different screening methods. Materials and Methods: We searched databases and then data were abstracted from each study. We evaluated articles based on different types of screening tests as well as screening age and intervals, and using incremental cost effectiveness ratio via calculating quality adjusted life years (QALY), or life years gained (LYG) per cost. We compared the incremental cost-effectiveness ratio (ICER) of each study using GDP per capita. Furthermore, we compared national guidelines with recommendations of cost-effectiveness studies in different countries. Results: A total of 21 articles met our criteria, of which 19 studies showed that HPV DNA testing, 13 suggested an age of 30 years or more, and 10 papers concluded that at least a 5-year or longer interval were the most cost-effective strategies. In some countries, the national guidelines did not match the recommendations of the cost-effectiveness studies. Conclusions: HPV testing, starting at age 30 years or older and repeated at 5-year or longer intervals, is the most cost-effective strategy in any setting. Closer collaboration with health economists is required during guideline development.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1703-1708
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• 2011

ZSM-5-$SO_3H$ efficiently catalyzed the one-pot three-component Mannich reaction of aldehydes, anilines, and ketones. ${\beta}$-Aminocarbonyl compounds were obtained in reasonable yields and excellent stereoselectivities when the reaction was carried out at room temperature under solvent-free conditions. Simple experimental conditions and product isolation procedure makes this protocol potential for the development of clean and environment-friendly strategy for the synthesis of ${\beta}$-amino-ketones. The catalyst was recovered and reused for subsequent runs.

• Structural Engineering and Mechanics
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• v.53 no.5
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• pp.1031-1049
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• 2015

This paper highlights the role of innovative vibration control system based on two promising properties in a parallel configuration. Hybrid device consists of two main components; recentering wires of shape memory alloy (SMA) and steel pipe section as an energy dissipater element. This approach concentrates damage in the steel pipe and prevents the main structural members from yielding. By regulation of the main adjustable design parameter, an optimum performance of the device is obtained. The effectiveness of the device in passive control of structures is evaluated through nonlinear time history analyses of a five-story steel frame with and without the hybrid device. Comparing the results proves that the hybrid device has a considerable potential to mitigate the residual drift ratio, peak absolute acceleration and peak interstory drift of the structure.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2461-2464
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• 2014

Background: Cancer accounts for 12.6% of total deaths in the world (just after heart disease). Materials and Methods: Frequency and age-specific incidence rates of breast and gynecologic cancers in Iran are calculated based on the dataset of the National Cancer Registry of Iran in 2005. Results: Gynecologic and breast cancer accounted for 7.6% and 25.6% of total cancer cases, respectively. Ovarian cancer was the most frequent gynecologic cancer followed by endometrium. Endometrial cancer revealed the highest age specific incidence rate followed by ovary (after 59 years). Conclusions: Regarding disease burden, breast and gynecologic cases account for 33.4% of total cancer patients. The age specific incidence rate is a useful guide in epidemiologic and future plans.

• Journal of Information Processing Systems
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• v.7 no.1
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• pp.151-158
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• 2011

Bivium is a simplified version of Trivium, a hardware profile finalist of the eSTREAM project. Bivium has an internal state size of 177 bits and a key length of 80 bits. In this paper, a guess and determine attack on this cipher is introduced. In the proposed method, the best linear approximations for the updating functions are first defined. Then by using these calculated approximations, a system of linear equations is built. By guessing 30 bits of internal state, the system is solved and all the other 147 remaining bits are determined. The complexity of the attack is O ($2^{30}$), which is an improvement to the previous guess and determine attack with a complexity of order O($2^{52.3}$).