• 한국재료학회지
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• 제18권3호
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• pp.153-158
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• 2008

Fe-aluminides have the potential to replace many types of stainless steels that are currently used in structural applications. Once commercialized, it is expected that they will be twice as strong as stainless steels with higher corrosion resistance at high temperatures, while their average production cost will be approximately 10% of that of stainless steels. Self-propagating, high-temperature Synthesis (SHS) has been used to produce intermetallic and ceramic compounds from reactions between elemental constituents. The driving force for the SHS is the high thermodynamic stability during the formation of the intermetallic compound. Therefore, the advantages of the SHS method include a higher purity of the products, low energy requirements and the relative simplicity of the process. In this work, a Fe-aluminide intermetallic compound was formed from high-purity elemental Fe and Al foils via a SHS reaction in a hot press. The formation of iron aluminides at the interface between the Fe and Al foil was observed to be controlled by the temperature, pressure and heating rate. Particularly, the heating rate plays the most important role in the formation of the intermetallic compound during the SHS reaction. According to a DSC analysis, a SHS reaction appeared at two different temperatures below and above the metaling point of Al. It was also observed that the SHS reaction temperatures increased as the heating rate increased. A fully dense, well-bonded intermetallic composite sheet with a thickness of $700\;{\mu}m$ was formed by a heat treatment at $665^{\circ}C$ for 15 hours after a SHS reaction of alternatively layered 10 Fe and 9 Al foils. The phases and microstructures of the intermetallic composite sheets were confirmed by EPMA and XRD analyses.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.77.1-77.1
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• 2013

Atomic layer deposition (ALD) is known for its self-limiting reaction, which offers atomic-level controllability of the growth of thin films for a wide range of applications. The self-limiting mechanism leads to very useful properties, such as excellent uniformity over a large area and superior conformality on complex structures. These unique features of ALD provide promising opportunities for future electronics. Although the ALD of Al2O3 film (using trimethyl-aluminum and water as a metal precursor and oxygen source, respectively) can be regarded as a representative example of an ideal ALD based on the completely self-limiting reaction, there are many cases deviating from the ideal ALD reaction in recently developed ALD processes. The nonconventional aspects of the ALD reactions may strongly influence the various properties of the functional materials grown by ALD, and the lack of comprehension of these aspects has made ALD difficult to control. In this respect, several dominant factors that complicate ALD reactions, including the types of metal precursors, non-metal precursors (oxygen sources or reducing agents), and substrates, will be discussed in this presentation. Several functional materials for future electronics, such as higher-k dielectrics (TiO2, SrTiO3) for DRAM application, and resistive switching materials (NiO) for RRAM application, will be addressed in this talk. Unwanted supply of oxygen atoms from the substrate or other component oxide to the incoming precursors during the precursor pulse step, and outward diffusion of substrate atoms to the growing film surface even during the steady-state growth influenced the growth, crystal structure, and properties of the various films.

• 전기화학회지
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• 제25권2호
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• pp.51-68
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• 2022

리튬금속전지는 높은 에너지 밀도를 구현시킬 수 있음에도 불구하고, 단락, 낮은 쿨롱 효율, 용량 손실, 사이클 성능 감소 등의 문제를 초래하는 덴드라이트 성장을 억제시키는 기술은 아직 학술연구 단계에 머물러 있다. 본 논문에서는 최근까지 발표된 리튬금속전극에서 덴드라이트 성장을 억제시킬 수 있는 방법을 4가지로 분류하여 분석해보았다. 즉, 리튬금속전극의 부피 팽창에 대응할 수 있는 유연한 SEI (solid electrolyte interface) 층, 덴드라이트 성장을 물리적으로 억제시킬 수 있는 SEI 지지층, 균일한 리튬 확산을 유도하여 리튬 성장을 조절하는 SHES (self-healing electrostatic shield) 메커니즘, 그리고 리튬의 균일한 전착을 유도하는 마이크로패터닝 등에 대해 연구된 사례들의 장단점을 분석하여, 리튬금속전극의 실용화 연구에 도움을 주고자 한다.

• Bulletin of the Korean Chemical Society
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• 제35권5호
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• pp.1469-1478
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• 2014

Use of acetonitrile in electrolytes promotes better operation of supercapacitors. Recent efforts show that electrolytes containing acetonitrile can also function in a wide range of operating temperatures. Therefore, this paper addresses the dielectric relaxation processes, structure and dynamic properties of the bulk acetonitrile at various temperatures. Systems of acetonitrile were modeled using canonical ensemble and simulated by employing Molecular Dynamics method. Results show that interactions among the molecules were correlated within a cut-off radius while parallel and anti-parallel arrangements are observed beyond this radius at relatively high and low temperatures respectively. Furthermore, effects of C-C-N and C-H bending modes were greatly appreciated on the power spectral density of time rate change of dipole-dipole correlations whereas frequency shifts were observed on all modes at the lowest temperature under consideration. Linear variations with temperature were depicted for reorientation times and self-diffusion coefficients. Shear viscosity was also computed with a good accuracy within a certain range of the temperature as well.

• 한국디지털정책학회:학술대회논문집
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• 한국디지털정책학회 2005년도 춘계학술대회
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• pp.13-28
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• 2005

The purpose of this study is to explore conquest plans of the barrier and resistance in innovation management. This paper focuses to understand the model of innovation that reflects adoption process stages and identify the factors that drive the resistance of consumers. Whenever organizations try to plan and implement some kind of innovation in organizations, they confront resistance in many ways. By understanding innovation resistance, organizations can not only design better innovations but can develop strategies to reduce resistance. Thus they accelerate innovation. Understanding the factors that drive the innovation resistance has important implications for both theoretical development and managerial action. These results indicate that people resist innovation strongly when it betrays their value, needs and beliefs or when they felt the pressure on self-conviction and mental risk, loss, and lack of knowledge.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.243-244
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• 2014

The opposed flow flame in a mesoscale channel was constructed to observe the flame stabilization behaviors at low strain rate conditions (<$10s^{-1}$). The purpose of this study is to get the overall flame behaviors of partially premixed flames with oxygen enhanced conditions at low strain rates. The oxygen ratio in oxidizer was changed from 18 to 30 %. Conclusively, the flame extinction limit approached to about $1s^{-1}$, and divided into three representative regimes corresponding to self propagating flame, transitional flame, quenching flame regimes.

• 한국의류학회지
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• 제21권1호
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• pp.67-81
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• 1997

The main purpose of this study was to compare the characteristics of male innovators and of male opinion leaders across product categories in terms of personality, attitudes, social participation, media usage patterns and demographic aspects. Six product categories such as clothing, cosmetics, small electronic appliances, medium-large electronic appliances, interior supplies and sports-leisure goods was used. A valid and reliable self-report scale was used to measure innovativeness and opinion leadership for 423 male adults living in social area Analyses showed that venturesomeness is the most common characteristics between innovators and opinion leaders across product categories. Innovators showed higher tendency of narcissism while opinion leadership showed higher cosmopolitainsm. Common charateristics of innovators and of opininion leaders of both clothing and cosmetics are cosmopolitanism, narcissism, exhibitionism, venturesomeness. The degrees of social participation and media usage patterns were different according to product categories for both innovators and opinion leaders. The implications of these findings for diffusion theory and merchandising were discussed.

• 한국진공학회지
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• 제2권4호
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• pp.474-479
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• 1993

Submicron contact hole filling with aluminum alloys has been achieved with a multistep metallization method, which utilizes a metal " flow" or self-diffusion process at elevated temperatures after the metal was sputter-deposited. A multi-chamber, modular sputtering system was employed to deposit aluminum alloys and subsequently to anneal the deposited metal films under vacuum at high temperatures. The film were deposited on 200 mm wafers with planar, dc magnetron sputtering sources without anysubstrate bias. The basic process steps studied for the multistep metallization include an initial layer deposition at low temperatures less than $100^{\circ}C$, and an annealin gstep at elevated temperatures, between 450 and $550^{\circ}C$. The degree of planarization or step coverage was dependent strongly upon the temperature and time of the flow step and complete filling of the submicron contacts with aluminum alloys was achieved. Responsible mechanisms for the enhancement in step coverge and factros determining uniform and reproducible flow of aluminum alloys during the high temperauture step are discussed.discussed.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2017년도 춘계학술발표대회
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• pp.1228-1231
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• 2017

The development of ICT brings the change in daily life and the digitized data are increasing in usage. The combination between GPS and internet results in extensive diffusion of space related information by way of smartphone, sensor and SNS. Jeju Island is only one special self-governing province in Republic of Korea and deserves to be proud of the unique culture, having those designated Intangible Cultural Heritage from UNESCO such as Culture of Jeju Haenyeo or Women Divers and Jeju Chilmeoridang Yeongdeunggut or Exorcism of Praying big Catch. In this paper, I suggest how to preserve fadable tradition economically and technically and expect to develop Haenyeo fitted portable sensors and IoT platform.

• Journal of Advanced Marine Engineering and Technology
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• 제34권3호
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• pp.369-375
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• 2010

The two-dimensional finite element formulation for the basic field equations governing electrochemical responses of ionic conducting polymer-metal composite(IPMC) actuators is proposed in the present study. Biaxial deformation of a platinum plated Nafion actuator having 4 electrodes is dominated by electro-osmosis of hydrated ions and self-diffusion of free water molecules. Some numerical studies for IPMC actuators with electric field are carried out in order to show the validity of the proposed formulation and electric field analysis for the initial condition of total charge distribution are conducted using commercial code ANSYS/Emag.