• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.210-210
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• 2013

그래핀은 뛰어난 기계적, 화학적, 광학적, 전기적 특성을 가지고 있는 2차원 물질로, 대면적 합성법과 전사 공정을 통해 다양한 기판에서의 사용이 가능해지면서 차세대 전자 소자로 활용하기위한 활발한 연구가 이루어지고 있다. 디스플레이, 태양전지의 전극과 전계 효과 트랜지스터의 채널로 적용한 연구에서 우수한 결과들을 보이고 있다. 특히, 금속/금속 산화물 전극은 염료 감응형 태양전지와 유기 발광 다이오드 구조에서 화학적으로 불안정할 뿐 아니라 일함수가 고정되어 쇼트키 접촉이 형성되면 저항을 낮추기 어렵지만, 그래핀은 금속/금속 산화물 전극보다 화학적으로 안정하고 일함수의 조절이 가능해 옴 접촉 형성에 용이하다. 그래핀의 일함수를 조절하는 연구는 크게 공유결합과 비공유 결합을 이용한 방법이 시도된다. 공유 결합을 이용한 방법은 합성과정에서 그래핀의 구조에 내재된 결함 혹은 새로운 결함을 형성하여 다른 원소를 첨가하는 방법이다. 이러한 방법은 그래핀의 결함 영역에서 작용하기 때문에 그래핀 전자 구조의 높은 수준 조절을 위해선 그래핀 구조의 파괴가 동반된다. 반면, 비공유 결합을 이용한 방법은 전하 이동 도핑 효과를 이용해 그래핀의 전자 구조를 제어하는 방법으로, 금속/금속산화물/기능기와 그래핀의 적층으로 복합 구조를 형성하는 방법이다. 금속/금속 산화물과의 복합구조는 안정적인 p-형 도핑이 보고되었지만, n-형 도핑은 대기중의 수분, 산소 그리고 기판과의 상호작용에 의해 대기중에서 불안정해 추가적인 피막공정이 요구된다. 기능기를 이용한 적층 구조는 그래핀과 기판사이의 상호작용 혹은 그래핀 전자 구조를 다양한 기능기를 이용해 제어하는 것으로, 이극성을 가진 자기정렬 단일층(self-assembled monolayers)이 대표적인 방법이다. 공간기(spacer)의 길이나 말단기(end group)의 종류로 p-형과 n-형의 도핑 수준을 제어할 수 있지만, 흡착기(chemisorbing groups)의 반응성이 기판의 화학적, 물리적 표면상태에 의존하기때문에 기판 선택이 제약되며 전처리 공정이 요구될 수 있는 한계가 있다. 본 연구에서는 다양한 기판에 적용가능한 용액 공정을 이용해 그래핀과 고분자를 적층하였고, 안정적이고 효과적으로 일함수를 낮추는 구조를 확인하였다.

• Journal of the Korean Regional Science Association
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• v.33 no.3
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• pp.61-78
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• 2017

Among several policies for industrial decentralization introduced since the 1960s, business relocation grant policies put a heavy financial burden on central and local governments. This study investigates the change in the likelihood of manufacturing establishments' relocation to the non-SMA associate with the change in business relocation grant policies. Using the mining and manufacturing survey data from 1996 to 2014, manufacturing firms' relocation decision model in nested logit structure was estimated. The data showed that the proportion of movements from the SMA to the non-SMA significantly increased after the introduction of the grant policies. However, estimation results of firms' relocation decision model indicated that the likelihood of firms relocating from the SMA to the non-SMA decreased after the introduction of the grant policies. In particular, firms' likelihood to move into the rural regions is even lower in the period of the grant extension. This suggests that increasing rate of relocations toward the rural regions may have been driven by the growing advantage of rural locations, such as low land rent and improvement in market accessibility, rather than the grants per se. This implies that the alleviation of physical and environmental constraints of the rural regions and the creation of business friendly environment such as easy access to premises at reasonable prices and strengthened linkage with the SMA, rather than simple provision of business relocation grants, needed to attract businesses in the rural regions.

• Journal of Wetlands Research
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• v.18 no.3
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• pp.313-323
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• 2016

Water temperature affects physical and biological processes in ecologies on river system and is important conditions for growth rate and spawning of fish species. The objective of this study is to compare models for water temperature during the summer season for the Fourchue River (St-Alexandre-de-Kamouraska, Quebec, Canada). For this, three different models, which are CEQUEAU, Auto-regressive Moving Average with eXogenous input and Nonlinear Autoregressive with eXogenous input, were applied and compared. Also, future water temperature in the Fourchue river were simulated and analyzed its result based on the CMIP5 climate models, RCP 2.6, 4.5, 8.5 climate change scenarios. As the result of the study, the water temperature in the Fourchue river are actually changed and median water temperature will increase $0.2{\sim}0.7^{\circ}C$ in June and could decrease by $0.2{\sim}1.1^{\circ}C$ in September. Also, the UILT ($24.9^{\circ}C$) for brook trout are also likely to occurred for several days.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.9 no.10
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• pp.753-762
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• 2019

It is very important to use the raw material in a particular field of research or education. Research without raw materials are difficult to prove and often remain hypothesis. The use of the raw material is also important in area studies that study specific areas. However, research of area studies, especially Western history, raw material and historical archives are very important data, but it is difficult to obtain and refer to these data due to physical or spatial constraints. In order to solve this problem, there is a method of collecting and providing historical archives, but it is currently difficult to find a case of providing overseas historical archives as a web system in Korea. Accordingly, in this paper proposes the necessity of collecting historical archives, the method of collection, and the method of digital archiving of collected data structurally and systematically. In this regard, investigate the existing research cases on the archive system and database design, and it description the differentiation between the existing systems and the modeling method proposed in this study. Also, to improve the efficiency of the search, it proposes a method of adding a tag table when database modeling.

• Progress in Medical Physics
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• v.16 no.1
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• pp.24-31
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• 2005

The stereotactic radiosurgery (SRS) describes a method of delivering a high dose of radiation to a small tar-get volume in the brain, generally in a single fraction, while the dose delivered to the surrounding normal tissue should be minimized. To perform automatic plan of the SRS, a new method of multi-isocenter/shot linear accelerator (linac) and gamma knife (GK) radiosurgery treatment plan was developed, based on a physical lattice structure in target. The optimal radiosurgical plan had been constructed by many beam parameters in a linear accelerator or gamma knife-based radiation therapy. In this work, an isocenter/shot was modeled as a sphere, which is equal to the circular collimator/helmet hole size because the dimension of the 50% isodose level in the dose profile is similar to its size. In a computer-aided system, it accomplished first an automatic arrangement of multi-isocenter/shot considering two parameters such as positions and collimator/helmet sizes for each isocenter/shot. Simultaneously, an irregularly shaped target was approximated by cubic structures through computation of voxel units. The treatment planning method by the technique was evaluated as a dose distribution by dose volume histograms, dose conformity, and dose homogeneity to targets. For irregularly shaped targets, the new method performed optimal multi-isocenter packing, and it only took a few seconds in a computer-aided system. The targets were included in a more than 50% isodose curve. The dose conformity was ordinarily acceptable levels and the dose homogeneity was always less than 2.0, satisfying for various targets referred to Radiation Therapy Oncology Group (RTOG) SRS criteria. In conclusion, this approach by physical lattice structure could be a useful radiosurgical plan without restrictions in the various tumor shapes and the different modality techniques such as linac and GK for SRS.

• Geophysics and Geophysical Exploration
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• v.16 no.3
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• pp.171-179
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• 2013

An automated ultrasonic velocity measurement system adopting pulse-echo-overlap (PEO) method has been constructed, which is known to be a precise and versatile method. It has been applied to velocity measurements for 5 kinds of engineering plastic cores and compared to first arrival picking (FAP) method. Because it needs multiple reflected waves and waves travel at least 4 times longer than FAP, PEO has basic restriction on sample length measurable. Velocities measured by PEO showed slightly lower than that by FAP, which comes from damping and diffusive characteristics of the samples as the wave travels longer distance in PEO. PEO, however, can measure velocities automatically by cross-correlating the first echo to the second or third echo, so that it can exclude the operator-oriented errors. Once measurable, PEO shows essentially higher repeatability and reproducibility than FAP. PEO system can diminish random noises by stacking multiple measurements. If it changes the experimental conditions such as temperature, saturation and so forth, the automated PEO system in this study can be applied to monitoring the velocity changes with respect to the parameter changes.

• Geophysics and Geophysical Exploration
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• v.4 no.4
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• pp.124-132
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• 2001

Electrical resistivity survey has been conducted for delineating geological fault structure in Kaekok-ri near Kyungju. In general, electrical resistivity survey has an advantage of searching buried faults and its traces compared with other geophysical survey methods. Distribution of electrical conductivity in the ground is influenced by the ratio of pores, groundwater and clay minerals. These properties are evidenced indirectly to explain for weathering condition, faults and fracture Bones. Thus the electrical resistivity survey can be an effective method to find buried faults. We have carried out two dimensional (2-D) interpretation by means of smoothness-constrained least-squares and finite element method. Field data used in this paper was acquired at Kaekok-ri, Wuedong-eup, Kyungju-si, where is Ulsan Fault and is close to the region in which debatable quaternary fault traces were found recently. The dipole-dipole array resistivity survey which could show the 2-D subsurface electrical resistivity structure, was carried out in the area with three lines. The results showed good property of fault, fracture zone and fault traces which we estimated were congruous with the results. Through this study, 2-D electrical resistivity survey interpretation for fault is useful to apply.

• Korean Journal of Cognitive Science
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• v.29 no.2
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• pp.105-120
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• 2018

Current neuroscience views the mind-body problem from the monistic perspective which claims that the human mind is the result of brain activity and that the mind shuts down when the brain does. However, a considerable number of lay people still believe in the existence of the soul and the afterlife, concepts that are hard to explain from the monistic perspective. This study examines whether lay people think that the mind of the dead is capable of exceeding the physical constraints if they believe that such mind exists. After reading one of three vignettes which describes the state of the protagonist as alive, dead, or brain dead, the participants evaluated the protagonist's general mental capacity and transcendental ability to obtain new information. The participants rated that the dead protagonist had more 'transcendental ability to obtain new information' than the alive one if they evaluated high general mental capacity to the protagonist. In addition, unlike the alive condition, in the dead and the brain dead condition, there was a correlation between the general mind capacity rating and the transcendental ability rating. The results suggest that lay people expect the mind of the alive and the dead to be different, as they believe the latter's general mind capacity connotes transcendental ability. We also found that the participants' religiosity affected their beliefs about the transcendental ability of dead person.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.914-916
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• 2013

Renewable energy from the environment in a variety of ways to obtain various forms of energy. Recent functional polymer composites (EAP) to take advantage of the pressure and vibration of physical energy into electrical energy storage, to take advantage of current collector technology is attracting attention. EAP, a type of IPMC (Ionic exchange Polymer Composite) got a hydrophilic properties, marine power plants is being studied as a source of energy. Studies using IPMC marine power plant because there is a constraint on the time, IPMC in real time, which can measure the power generated by the system is required, Due to the nature of the power plant to be floating in the sea through the power cable and data transmission measurement system is hard drive self-generation and wireless data transmission system is required. In this study, IPMC marine power plant is to develop a system of monitoring. IPMC for several power plants to build individual current-voltage measurement system, CAN communication with the main system to collect all the information and wireless data transmission to occur, and Generation of electricity using solar energy to building systems in real-time without an external power supply to drive the measuring system is to develop a monitoring system.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.4
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• pp.284-288
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• 2009

With explosively growing PPI databases, the computational approach for a prediction and configuration of PPI network has been a big stream in the bioinformatics area. Recent researches gradually consider physicochemical properties of proteins and support high resolution results with integration of experimental results. With regard to current research trend, it is very close future to complete a PPI network configuration of each organism. However, direct applying the PPI network to real field is complicated problem because PPI network is only a set of co-expressive proteins or gene products, and its network link means simple physical binding rather than in-depth knowledge of biological process. In this paper, we suggest a protein functional flow model which is a directed network based on a protein functions' relation of signaling transduction pathway. The vertex of the suggested model is a molecular function annotated by gene ontology, and the relations among the vertex are considered as edges. Thus, it is easy to trace a specific function's transition, and it can be a constraint to extract a meaningful sub-path from whole PPI network. To evaluate the model, 11 functional flow models of Homo sapiens were built from KEGG, and Cronbach's alpha values were measured (alpha=0.67). Among 1023 functional flows, 765 functional flows showed 0.6 or higher alpha values.