• 반도체디스플레이기술학회지
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• 제2권2호
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• pp.9-15
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• 2003

This paper proposes a thickness measurement method of silicon-oxide and poly-silicon film deposited on 12" silicon wafer for spin etcher. Halogen lamp is used as a light source for generating a wide-band spectrum, which is guided and focused on the wafer surface through a optical fiber cable. Interference signal from the film is detected by optical sensor to determine the thickness of the film using spectrum analysis and several signal processing techniques including curve-fitting and adaptive filtering. Test wafers with three kinds of priori-known films, polysilicon(300 nm), silicon-oxide(500 nm) and silicon-oxide(600 nm), are measured while the wafer is spinning at 20 Hz and DI water flowing on the wafer surface. From experiment results the algorithm presented in the paper is proved to be effective with accuracy of maximum 0.8% error.rror.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.3085-3089
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• 2008

In order to reduce NOx and Soot emissions simultaneously, characteristics of diesel spray and combustion were investigated by numerical simulation with StarCD in this paper. This work focuses on effect of Spin Injection. A simulation model of combustion, spray and emissions is developed for heavy duty marine diesel engine application. Simulation is performed with change of spray angle between first and second directions at fixed engine speed, injection timing, injection duration and etc. The results show that Spin Spray Injection method can reduce NOx emission. And the results show that the 1st injection considerably interfere with 2nd injection characteristics.

• 한국항공우주학회지
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• 제40권8호
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• pp.726-736
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• 2012

본 논문은 KC-100 소형민항기의 스핀시험을 위해 장착될 스핀회복장치의 설계 및 지상활주 전개 시험에 대해 기술하였다. 스핀회복장치에 대한 상세 설계 단계에서 공력, 구조, 안정성, 조종성 등에 대한 해석적 결과를 토대로 낙하산 단위면적당 라이저 길이, 낙하산 다공성, 낙하산 펼침 시간, 및 전개방법 등의 설계 변수를 결정했다. 본 시스템의 검증을 위해 항공기에 스핀회복장치를 장착한 상태에서 기능점검 후 KC-100 고속활주 중 스핀슈트 전개를 수행했다.

• Journal of Magnetics
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• 제19권3호
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• pp.227-231
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• 2014

We fabricated textured polycrystalline $CoFe_2O_4$ thin films on $Pt(111)/TiO_2/SiO_2/Si$ substrate through a sol-gel method. We varied the thickness of the films, by using precursor solutions with different concentrations of 0.1, 0.2, and 0.3 M, and by depositing 5, 8, or 10 layers on the substrate by spin-coating. X-ray diffraction spectra indicated that when the precursor concentration of the solution was higher than 0.1 M, the spin-coated films were preferentially oriented in the <111> direction. Inspection of the surface morphology by scanning electron microscopy revealed that $CoFe_2O_4$ thin films prepared with 0.2 M solution and 5-time spin-coatings had smoother surface, as compared to the other conditions. Each coating had an average thickness of about 50 nm. The magnetic properties measured by vibrating sample magnetometer showed magnetic anisotropy, as evidenced from the difference in the in-plane and out-of-plane hysteresis loops, which we attributed to the textured orientation of the $CoFe_2O_4$ thin films.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 춘계학술발표강연 및 논문개요집
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• pp.19-19
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• 2003

The injection of spins into nonmagnetic semiconductors has recently attracted great interest due to the potential to create new classes of spin-dependent electronic devices. A recent strategy to achieve control over the spin degree of freedom is based on dilute ferromagnetic semiconductors. Ferromagnetism has been reported in various semiconductor groups including II-Ⅵ, III-V, IV and II-IV,-V$_2$, which will be reviewed. On the other hand, to date the low solubility of magnetic ions in non-magnetic semiconductor hosts and/or low Curie temperature have limited the opportunities. Therefore the search for other promising ferromagnetic semiconducting materials, with high magnetic moments and high Curie temperatures (Tc), is of the utmost importance. In this talk, we also introduce new pure ferromagnetic semiconductors, MnGeP$_2$ and MnGeAs$_2$, exhibiting ferromagnetism and a magnetic moment per Mn at 5K larger than 2.40 ${\mu}$B. The calculated electronic structures using the FLAPW method show an indirect energy gap of 0.24 and 0.06 eV, respectively. We have observed spin injection in MnGeP$_2$ and MnGeAs$_2$ magnetic tunnel junctions through semiconducting barriers.

• 반도체디스플레이기술학회지
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• 제17권3호
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• pp.27-30
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• 2018

In this study, ZnO film was deposited on polycarbonate substrate by spin-spray method at low substrate temperature of $85^{\circ}C$. Surface morphology of ZnO films was changed by adding citrate from rod to dense structure. As-deposited ZnO film indicated high transmittance above 80%. In case of the resistivity, as-deposited ZnO film had high resistivity due to the existence of organic substance in the film. However, organic substance was removed and resistivity was decreased to $3.9{\times}10^{-2}{\Omega}{\cdot}cm$, after UV irradiation.

• 한국국방경영분석학회지
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• 제36권3호
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• pp.15-27
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• 2010

민군 겸용기술은 민간부문은 물론 군사부문에도 이용되는 기술로 이러한 기술은 산업의 경쟁력 확보와 안보 역량을 동시에 충족한다는 측면에서 볼 때 저비용 고효율의 기술이라 할 수 있다. 따라서 이러한 민군 겸용기술 개발을 활성화하기 위한 기술 기획 방법 및 이와 관련된 연구의 필요성은 제기되어 왔으나 실제 이와 관련된 연구는 부족한 실정이다. 본 연구는 민군 겸용기술 개발을 활성화하기 위한 기술 기획에 있어 기술의 겸용성과 이전을 고려한 보다 구체적이고 정량적인 절차를 제시하는데 목적이 있다. 이를 위해 특허와 특허 인용 그리고 특허와 산업 연관관계를 바탕으로 한 기술 개발 우선 순위 도출 과정을 체계적으로 제시하였으며 이 과정에서 계층분석 기법을 적용하였다. 제안한 방법의 유용성을 검증하기 위하여 국방 기술분야 중 항공기 무기체계를 대상으로 사례연구를 수행하였으며, 본 연구 결과는 국방 분야 기술 수요 도출시 민수화 가능성이 높은 기술을 제시함으로써 민군 겸용기술을 발굴하는데 기여할 것으로 기대된다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.127-131
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• 2006

There are being a lot of studies for achievement of high speed Dehydration, high-strength and Lightweight of washing machine in the latest washing machine business. It is essential that Press-joining Strength of Spin Drum Seaming division is improved .to attain that target. Generally, we are using Mechanical press-joining by Seaming and T.I.G (Tungsten Inert Gas) welding among part joint method. Mechanical press-joining method that is mainly using for Stainless Steel (STS430) Drum have lots of merit that consumption of energy is low more than welding and production costs cut down and generation of the corrosion is solved by removing weld zone defect and materials having different properties are enable to join without special equipment. But, it is difficult to realize joint strength required at high speed operation because joint strength of mechanical press-joining method is low remarkably in comparison with welding. Also, there are a lot of analysis difficulties and very limited research is under way due to the dynamic factor such as multistage plastic working, elastic recovery, residual stress etc. The results of this study show optimal joining condition for mechanical press-joining by performing lots of tensile joining strength test with various specimen under multi-change of important design factor such as seaming width, bead area and bead depth etc.

• 전기학회논문지
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• 제58권11호
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• pp.2214-2218
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• 2009

Dye-sensitized solar cell (DSC) has been considered as a possible alternative to current silicon based p-n junction photovoltaic devices due to its advantages of high efficiency, simple fabrication process and low production cost. Numerous researches for high efficient DSC in the various fields are under way even now. Among them, the compact layer, which prevents the back electron transfer between transparent conductive oxides and the redox electrolyte, is fabricated by various methods such as a ZnO dip-coating, $TiCl_4$ dip-coating, and Ti sputtering. In this study, we tried to fabricate the $TiO_2$ compact layer by the spin-coating method using aqueous $TiCl_4$ solution. The effect of the spin-coating method was checked as compared with conventional dip-coating method. As a result, DSC with a spin-coated compact layer had 33.4% and 6% better efficiency than standard DSC and DSC with a dip-coated compact layer.

• Bulletin of the Korean Chemical Society
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• 제16권6호
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• pp.547-552
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• 1995

As an extension to the Kramers' restricted Hartree-Fock (KRHF) method [J. Comp. Chem., 13, 595 (1992)], we have implemented the Kramers' restricted configuration interaction (KRCI) program in order to calculate excited states as well as the ground state of polyatomic molecules containing heavy atoms. This KRCI is based on determinants composed of the two-component molecular spinors which are generated from KRHF calculations. The Hamiltonian employed in the KRHF and KRCI methods contains most of all the important relativistic effects including spin-orbit terms through the use of relativistic effective core potentials (REP). The present program which is limited to a small configuration space has been tested for a few atoms and molecules. Excitation energies of the group 14 and 16 elements calculated using the present KRCI program are in good accordance with the spectroscopic data. Calculated excitation energies for many Rydberg states of K and Cs indicate that spin-orbit terms in the REP, which are derived for the ground state, are also reliable for the description of highly excited states. The electronic states of the polyatomic molecule CH3I are probed from the molecular region to the dissociation limit. Test calculations demonstrate that the present KRCI is a useful method for the description of potential energy surface of polyatomic molecules containing heavy atoms.