• 대한화학회지
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• 제29권1호
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• pp.52-60
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• 1985

본 연구는 대기중의 질소산화물(이하 NO$_x$로 약기)을 신속 정확하게 측정하기 위해 현 방법을 개선한 것으로써, 대기중의 NO$_x$를 0.03${\%}$ 과산화수소(H$_2$O$_2$)를 함유한 0.1N수산화나트륨의 알칼리성 흡수액에 흡수 시킴으로써, 정량이 가능했다. 완전한 흡수를 위해서는 100ppm정도의 NO$_x$인 경우 흡수액과 2분간의 진탕이 필요했으나, 고농도의 NO$_x$ (>200 ppm 이상)인 경우에는 산화제로 공기나 산소기체를 첨가시켜 반응물을 맹렬히 진탕시켜 줌으로써 30분이내에 완전한 산화흡수가 가능했다. 남아있는 여분의 H$_2$O$_2$는 흡광도에 미치는 영향이 매우 크지만 아연분말 0.5g으로서 완전히 분해할 수 있었으며, 시료용액은 질산이온에서 아질산이온으로의 환원이 가능하도록 완충용액으로 액성이 pH 6.1~6.6으로 조정되어야 했다. 흡수된 NO$_x$는 sulfanilamide와 NEDA로서 diazo coupling 반응시켜 비색 정량하였다. 이상의 방법은 몰흡광계수가 크며(4.48 ${\times}$ 10$^4$), 한국공업규격에 채택된 O$_3$산화-아연 환원 NEAD 법보다 훨씬 신속, 간편할 뿐 아니라. 측정값의 재현성이 우수한 배기가스중의 NO$_x$분석법임이 확인되었다.

• Journal of Electrical Engineering and Technology
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• 제11권6호
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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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• 제30권8호
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• pp.1877-1880
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• 2009

• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.489-492
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• 2009

• 대한전자공학회논문지SD
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• 제43권3호
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• pp.48-58
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• 2006

본 논문은 가산기 기반 DA(Distributed Arithmetic: 분산 산술연산)구조로서 ROM과 같은 일반적인 메모리가 사용되지 않는 8x8의 2차원 DCT(Discrete Cosine Transform)/IDCT(Inverse DCT) 프로세서를 제안 설계하였다. 제안된 논문은 DCT와 IDCT의 계수 행렬에서 하드웨어를 줄이기 위해 계수 행렬의 홀수 부분을 공유하였고, 2차원 DCT/IDCT 프로세서의 계수 연산을 위해 단지 29개의 가산기만을 사용하였다. 이는 8x8 1차원 DCT NEDA(NEw DA)구조에서의 가산기 수 보다 48.6%를 감소 시켰다. 또한, 기존의 전치메모리와는 다른 새로운 전치네트워크 구조를 제안하였다. 제안된 전치네트워크 구조에서는 전치메모리 블록 대신 하드웨어를 줄이기 위해 레지스터 형태의 새로운 레지스터 블록 전치네트워크 형태를 제안하였다. 제안된 전치네트워크 블록은 64개의 레지스터를 사용하며, 이는 일반적인 메모리를 사용하는 기존의 전치메모리 구조에 사용된 트랜지스터 수 보다 18%가 감소하였다. 또한 처리율 향상을 위해 새롭게 적용되고 있는 방식으로, 입력 데이터에 대해 매 클럭 주기마다 8개의 화소데이터를 받아서 8개의 화소데이터를 처리하도록 하여 출력하는 비트 병렬화 구조로 설계하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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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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• 제32권5호
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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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• 제53권5호
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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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• 제15권6호
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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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• 제7권1호
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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($2^{52.3}$).