• Proceedings of the KWS Conference
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• 2003.11a
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• pp.141-143
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• 2003

• Communications of Mathematical Education
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• v.21 no.1 s.29
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• pp.65-79
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• 2007

In this paper we study various aspects of Catalan number with its focus on creative output. As a result we we develop teaching and learning materials for the gifted students which can lead to creative output at the middle school level.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05a
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• pp.191-196
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• 1996

이 논문에서는 Gadolinia, Erbia, IFBA를 비교평가 대상 독물질로 선정하여, 영광 3/4호기 노심을 대상으로 주기길이별 독봉장전노심을 구성하여 노심핵특성인자들을 비교평가하였다. 주기길이측면에서 Gd 장전노심과 IFBA 장전노심이 비슷하게 예측되었으며 Erbia 장전노심이 약 10∼13일 정도 작게 예측되었다. 냉각재 온도계수 측면에서는 Erbia 장전노심의 타 독물질 장전노심에 비해 우수하게 평가되었다. 최대 Fr 인자 측면에서는 Erbia 장전노심과 IFBA 장전노심이 거의 비슷한 수준에서 우수하게 평가되었으며 Gd 장전노심은 이 측면에서 취약한 것으로 평가되었다.

• 한국연소학회:학술대회논문집
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• 2007.05a
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• pp.86-91
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• 2007

A study was performed to understand self-excited pressure fluctuations in the lean premixed flames and to evaluate the effect of Helmholtz resonator on the pressure fluctuations. As low-frequency pressure fluctuations have been reported to cause fatal damage to the combustor and the entire system, Helmholtz-type resonators, which reduce the damage by low-frequency pressure fluctuation in the combustor, are attached to the channel of unburned mixture flow. It is found that the range of low-frequency pressure fluctuations of flame mode 2 is narrowed by the attachment of Helmholtz resonators. From this result, if Helmholtz-type resonators are applied to actual gas turbine combustor, it is confirmed that Helmholtz resonators attached on the fuel discharge hole are also effective for narrowing the range of flame mode 2

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.275-278
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• 2003

The crop coefficient of rice were investigated using the Penman-Monteith method in Cheongju, in central South Korea. The mean actual evapotranspiration of rice was 4.8 mm/d, and highest evapotranspiration of rice was 6.6 mm/d in late August in 2001. The crop coefficient of rice showed 1.0 in early irrigation season, but over 1.5 in late irrigation season. The mean crop coefficient of rice in central area(1.16) was lower than that in southern area(1.49)

• Journal of ILASS-Korea
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• v.27 no.1
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• pp.26-35
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• 2022

Electrospray is a method of atomizing fluid using high voltage supply and capable of generating continuous flow and coherent size of droplets. Electrical system and properties of fluids has enabled electrospray to have various spray modes. However, its studies have been confined only in Cone jet, which is more stable and easier to manipulate droplets' size than other spraying modes. Therefore, it is necessary to investigate and compare other spraying modes based on experimental parameters and physical properties of fluids. This research paper identified nine different spray modes. It was found out that Sauter Mean Diameter (SMD) is proportional to flow rate of fluids and maximum difference among spray modes was 1.7 times. On the other hand, SMD standard deviation had low variations on specific flow rates of fluids. Pulsed jet mode recorded the largest SMD standard deviation, while Spindle recorded the lowest.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.05a
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• pp.199-202
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• 2005

본 연구는 cytochrome B 유전자의 PCR-RFLP 분석기법을 이용하여 다양한 가금류 식육자원 및 각종 가공 육제품의 원료육에 대한 정확하고 재현성 높은 축종 및 육종 감별기술을 개발하기 위하여 수행되었다. 국내에서 유통되고 있는 종간 근연관계가 높은 3종의 가금육(닭, 칠면조 및 오리)의 육류에서 분리한 DNA 시료를 대상으로 cytochrome B 유전자의 특정 염기서열을 포함하는 primer를 설계 제작하여 PCR-RFLP 분석을 실시하였다. 각 축종의 근육조직으로부터 genomic DNA를 추출하고 PCR 증폭 반응을 수행한 후 얻어진 PCR 증폭산물(359 bp)을 두 종류의 제한효소(HaeШ 및 Hinf I)로 각각 절단한 결과 특히, HaeШ 제한효소에서 가금류의 축종 간 그리고 제한효소 간에 명확한 차이를 보이는 종 특이적인 PCR-RFLP marker를 검출하였다. 따라서, 본 연구에서 개발한 cytochrome B 유전자의 가금류 종 특이적 PCR-RFLP marker는 가금류의 식육 및 가공 육제품의 육종 및 축종 판별에 매우 유용한 DNA marker로 이용될 수 있을 것이다.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.10a
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• pp.123-126
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• 2005

본 연구는 고등동물의 불포화지방산 생합성의 핵심 효소로 알려져 있는 Stearoyl-CoA desaturase(SCD) 유전자의 특정한 단일염기다형(single nucleotide polymorphism; SNP)이 한우의 도체 및 육질형질에 미치는 영향을 분석하기 위해 SCD 유전자의 Intron 7번 영역의 특정부위를 포함하는 primer를 제작하고, 염기서열 분석을 통하여 유전자 구조를 해석한 결과 총 211bp 크기를 갖는 염기서열의 122번째에서 아데닌(A)${\leftrightarrow}$구아닌(G) 염기치환으로 발생한 단일염기다형(SNP) 부위를 발견하였다. 이들 단일염기다형 염기서열 부위를 PCR-SSCP(single-strand conformation polymorphism) 기법을 이용하여 분석한 결과 3종류의 SNP 유전자형(A/A, A/G 및 G/G)을 검출하였다. 이 가운데 A/G 유전자형이 한우의 근내지방도와 등지방두께와 고도의 유의적 연관성이 있다는 새로운 사실을 발견하였다. 따라서, 본 연구를 통해 개발된 한우 SCD 유전자의 특정한 단일 염기다형 표지인자는 한우의 연령 및 성별에 관계없이 육질이 우수한 고급육을 생산하는 우량 한우의 조기식별에 매우 유용한 DNA 표지인자로 활용할 수 있을 것으로 기대된다.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.8 no.3
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• pp.239-242
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• 2015

In this paper, we propose a walking assisting system for blind people using Android smartphone and Arduino board. In our proposed system, we use an Android smartphone case and an external ultrasonic sensor to detect the obstacles ahead. In this manner, blind people is able to aware unexpected objects by smartphone speakers or vibration functionality. In addition, the walking assisting system is also designed a notice system which will be triggered by built-in smartphone camera flash when blind people walk in some darkness place. The experimental results from real experiments on blind people have demonstrated the applicability of our walking assisting system, when it not only efficiently helps blind people avoid obstacles ahead but also possible traffic collisions in darkness condition.

• Applied Chemistry for Engineering
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• v.25 no.5
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• pp.447-454
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• 2014

Organic solar cells (OSCs) have intensively studied in recent years due to their advantages such as cost effectiveness and possibility of applications in flexible devices. In spite of the high power conversion efficiency (PCE) of 10 %, the OSCs still have a draw back of their low environmental stability due to the oxidization of aluminum cathode and etching of transparent conducting oxide as electrode. To solve these problems, the inverted structured OSCs (I-OSCs) having greatest potential for achieving an improvement of device performances are suggested. Therefore, there are a lot of studies to develope of interface layer based on organic/inorganic materials for the electron transport layer (ETL) and passivation layer, significant advancements in I-OSCs have driven the development of interface functional materials including electron transport layer. Recent efforts to employing 2D/3D zinc oxide (ZnO) based ETL into I-OSCs have produced OSCs with a power conversion efficiency level that matches the efficiency of ~9 %. In this review, the technical issues and recent progress of ZnO based ETL in I-OSCs to enhancement of device efficiency and stability in terms of materials, process and characterization have summarized.