• Title/Summary/Keyword: property ($D_k$)

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Discharge Characteristics of Plasma Jet Doping Device with the Atmospheric and Ambient Gas Pressure (플라즈마 제트 도핑 장치의 대기 및 기체의 압력 변화에 대한 방전 특성)

  • Kim, J.G.;Lee, W.Y.;Kim, Y.J.;Han, G.H.;Kim, D.J.;Kim, H.C.;Koo, J.H.;Kwon, G.C.;Cho, G.S.
    • Journal of the Korean Vacuum Society
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    • v.21 no.6
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    • pp.301-311
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    • 2012
  • Discharge property of plasma jet devices is investigated for the application to the doping processes of crystalline solar cells and others. Current-voltage characteristics are shown as the typical normal-glow discharge in the various gas pressure of plasma jets, such as in the atmospheric plasma jets of Ar-discharge, in the ambient pressure of atmospheric discharge, and in the ambient Ar-pressure of Ar-discharge. The discharge voltage of atmospheric plasma jet is required as low as about 2.5 kV while the operation voltage of low pressure below 200 Torr is low as about 1 kV in the discharge of atmospheric and Ar plasma jets. With a single channel plasma jet, the irradiated plasma current on the doped silicon wafer is obtained high as the range of 10~50 mA. The temperature increasement of wafer is normally about $200^{\circ}C$. In the result of silicon wafers doped by phosphoric acid with irradiating the plasma jets, the doping profiles of phosphorus atoms shows the possibility of plasma jet doping on solar cells.

Light Emission and Plasma Property in the External Electrode Fluorescent Lamps (외부전극 형광램프의 발광 및 플라즈마 특성)

  • Ahn, S.;Lee, M.;Jeong, J.;Kim, J.;Yoo, D.;Koo, J.;Kang, J.;Hong, B.;Choi, E.;Cho, G.
    • Journal of the Korean Vacuum Society
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    • v.16 no.3
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    • pp.172-180
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    • 2007
  • A new diagnostics of plasma electron temperature and plasma density is introduced with the observation of the light emission along the tube of external electrode fluorescent lamps. With two different methods operating an external electrode fluorescent lamp of outer diameter 4.0 mm and length 860 mm for the back-light source of 37-inch LCD-TVs, the lighting modes and the plasma properties are investigated. In the center balance operation, the light-emission propagates simultaneously from both sides of the high voltage electrodes to the center of the lamp, while in conventional operation the light-emission propagates from the one end of a high voltage to the other ground electrode. In the operation value of luminance $10,000{\sim}15,000cd/m^2$, the electron plasma thermal energy $(kT_e)$ is about $1.3{\sim}2.7eV$ with the electron density $(n_e)$ is about $(1.6{\sim}3.6){\times}10^{16}m^{-3}$.

Electro-Optical Characteristics and Analysis of 1×1 mm2 Large-Area InGaN/GaN Green LED (1×1 mm2 대면적 녹색 LED의 전기 광학적 특성 분석)

  • Jang, L.W.;Jo, D.S.;Jeon, J.W.;Ahn, Tae-Young;Park, M.J.;Ahn, B.J.;Song, J.H.;Kwak, J.S.;Kim, Jin-Soo;Lee, I.H.;Ahn, H.K.
    • Journal of the Korean Vacuum Society
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    • v.20 no.4
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    • pp.288-293
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    • 2011
  • We investigated the effects of piezoelectric field on the electro-absorption characteristics in InGaN/GaN multiple-quantum well (MQW) green light emitting diodes (LED). Double crystal X-ray diffraction measurement was performed to study the crystalline property and indium (In) composition in the MQW active layer. To measure the electro-luminescence and electro-reflectance (ER) spectroscopy, we fabricated the $1{\times}1\;mm^2$ large-area green LED chip. The piezoelectric field inside the LED structure was evaluated from the Vcomp in active layer by the ER spectra. Finally, we analyzed the electro-absorption characteristics of the green LED by using the photo-current spectroscopy.

Social Tagging-based Recommendation Platform for Patented Technology Transfer (특허의 기술이전 활성화를 위한 소셜 태깅기반 지적재산권 추천플랫폼)

  • Park, Yoon-Joo
    • Journal of Intelligence and Information Systems
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    • v.21 no.3
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    • pp.53-77
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    • 2015
  • Korea has witnessed an increasing number of domestic patent applications, but a majority of them are not utilized to their maximum potential but end up becoming obsolete. According to the 2012 National Congress' Inspection of Administration, about 73% of patents possessed by universities and public-funded research institutions failed to lead to creating social values, but remain latent. One of the main problem of this issue is that patent creators such as individual researcher, university, or research institution lack abilities to commercialize their patents into viable businesses with those enterprises that are in need of them. Also, for enterprises side, it is hard to find the appropriate patents by searching keywords on all such occasions. This system proposes a patent recommendation system that can identify and recommend intellectual rights appropriate to users' interested fields among a rapidly accumulating number of patent assets in a more easy and efficient manner. The proposed system extracts core contents and technology sectors from the existing pool of patents, and combines it with secondary social knowledge, which derives from tags information created by users, in order to find the best patents recommended for users. That is to say, in an early stage where there is no accumulated tag information, the recommendation is done by utilizing content characteristics, which are identified through an analysis of key words contained in such parameters as 'Title of Invention' and 'Claim' among the various patent attributes. In order to do this, the suggested system extracts only nouns from patents and assigns a weight to each noun according to the importance of it in all patents by performing TF-IDF analysis. After that, it finds patents which have similar weights with preferred patents by a user. In this paper, this similarity is called a "Domain Similarity". Next, the suggested system extract technology sector's characteristics from patent document by analyzing the international technology classification code (International Patent Classification, IPC). Every patents have more than one IPC, and each user can attach more than one tag to the patents they like. Thus, each user has a set of IPC codes included in tagged patents. The suggested system manages this IPC set to analyze technology preference of each user and find the well-fitted patents for them. In order to do this, the suggeted system calcuates a 'Technology_Similarity' between a set of IPC codes and IPC codes contained in all other patents. After that, when the tag information of multiple users are accumulated, the system expands the recommendations in consideration of other users' social tag information relating to the patent that is tagged by a concerned user. The similarity between tag information of perferred 'patents by user and other patents are called a 'Social Simialrity' in this paper. Lastly, a 'Total Similarity' are calculated by adding these three differenent similarites and patents having the highest 'Total Similarity' are recommended to each user. The suggested system are applied to a total of 1,638 korean patents obtained from the Korea Industrial Property Rights Information Service (KIPRIS) run by the Korea Intellectual Property Office. However, since this original dataset does not include tag information, we create virtual tag information and utilized this to construct the semi-virtual dataset. The proposed recommendation algorithm was implemented with JAVA, a computer programming language, and a prototype graphic user interface was also designed for this study. As the proposed system did not have dependent variables and uses virtual data, it is impossible to verify the recommendation system with a statistical method. Therefore, the study uses a scenario test method to verify the operational feasibility and recommendation effectiveness of the system. The results of this study are expected to improve the possibility of matching promising patents with the best suitable businesses. It is assumed that users' experiential knowledge can be accumulated, managed, and utilized in the As-Is patent system, which currently only manages standardized patent information.

Distribution and Behavior of Soil CO2 in Pohang area: Baseline Survey and Preliminary Interpretation in a Candidate Geological CO2 Storage Site (포항 지역 토양 CO2의 분포 및 거동 특성 연구: CO2 지중저장 부지 자연 배경 조사 및 예비 해석)

  • Park, Jinyoung;Sung, Ki-Sung;Yu, Soonyoung;Chae, Gitak;Lee, Sein;Yum, Byoung-Woo;Park, Kwon Gyu;Kim, Jeong-Chan
    • Journal of Soil and Groundwater Environment
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    • v.21 no.1
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    • pp.49-60
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    • 2016
  • Distribution and behavior of baseline soil CO2 were investigated in a candidate geologic CO2 storage site in Pohang, with measuring CO2 concentrations and carbon isotopes in the vadose zone as well as CO2 fluxes and concentrations through ground surface. This investigation aimed to assess the baseline CO2 levels and to build the CO2 monitoring system before injecting CO2. The gas in the vadose zone was collected using a peristaltic pump from the depth of 60 cm below ground surface, and stored at gas bags. Then the gas components (CO2, O2, N2, CH4) and δ13CCO2 were analyzed using GC and CRDS (cavity ringdown spectroscopy) respectively in laboratory. CO2 fluxes and CO2 concentrations through ground surface were measured using Li-COR in field. In result, the median of the CO2 concentrations in the vadose zone was about 3,000 ppm, and the δ13CCO2 were in the wide range between −36.9‰ and −10.6‰. The results imply that the fate of CO2 in the vadose zone was affected by soil property and vegetations. CO2 in sandy or loamy soils originated from the respiration of microorganisms and the decomposition of C3 plants. In gravel areas, the CO2 concentrations decreased while the δ13CCO2 increased because of the mixing with the atmospheric gas. In addition, the relation between O2 and CO2, N2, and the relation between N2/O2 and CO2 implied that the gases in the vadose zone dissolved in the infiltrating precipitation or the soil moisture. The median CO2 flux through ground surface was 2.9 g/m2/d which is lower than the reported soil CO2 fluxes in areas with temperate climates. CO2 fluxes measured in sandy and loamy soil areas were higher (median 5.2 g/m2/d) than those in gravel areas (2.6 g/m2/d). The relationships between CO2 fluxes and concentrations suggested that the transport of CO2 from the vadose zone to ground surface was dominated by diffusion in the study area. In gravel areas, the mixing with atmospheric gases was significant. Based on this study result, a soil monitoring procedure has been established for a candidate geologic CO2 storage site. Also, this study result provides ideas for innovating soil monitoring technologies.

An Embedded Watermark into Multiple Lower Bitplanes of Digital Image (디지털 영상의 다중 하위 비트플랜에 삽입되는 워터마크)

  • Rhee, Kang-Hyeon
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.43 no.6 s.312
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    • pp.101-109
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    • 2006
  • Recently, according to the number of internet in widely use and the development of the related application program, the distribution and use of multimedia content(text, images, video, audio etc.) is very easy. Digital signal may be easily duplicated and the duplicated data can have same quality of original data so that it is difficult to warrant original owner. For the solution of this problem, the protection method of copyright which is encipher and watermarking. Digital watermarking is used to protect IP(Intellectual Property) and authenticate the owner of multimedia content. In this paper, the proposed watermarking algerian embeds watermark into multiple lower bitplanes of digital image. In the proposed algorithm, original and watermark images are decomposed to bitplanes each other and the watermarking operation is executed in the corresponded bitplane. The position of watermark image embedded in each bitplane is used to the watermarking key and executed in multiple lower bitplane which has no an influence on human visual recognition. Thus this algorithm can present watermark image to the multiple inherent patterns and needs small watermarking quantity. In the experiment, the author confirmed that it has high robustness against attacks of JPEG, MEDIAN and PSNR but it is weakness against attacks of NOISE, RNDDIST, ROT, SCALE, SS on spatial domain when a criterion PSNR of watermarked image is 40dB.

An Empirical Study on the Obstacle Factor of Standardization and Overcoming the Obstacles of Enterprises Using the Structural Equation Model (구조방정식 모형을 활용한 표준화 장애요인과 기업의 장애극복방안에 관한 실증연구)

  • Jeong, Myoung-Sun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.3
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    • pp.171-179
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    • 2018
  • In order to ensure the interoperability of products and technologies, companies apply standard technology in R&D but encounter various obstacles in this process, which they try to overcome through active standardization activities. Various studies have investigated the obstacles and coping strategies of companies in the R&D process. However, studies on the obstacles and coping strategies in the standardization process are insufficient, and the types of obstacles related to standardization, so a variety of studies are also needed on the types of activities. In this study, we tried to determine the types of obstacles related to standardization and to examine how these obstacles affect the standardization activities of companies. The analysis used the data from the 'National Standards Survey' which was conducted by the Korean Standards Association in Korea for companies engaged in the electrical, electronic, and information-related fields in Korea. The relationship between standard-related difficulties, needs and standardization activities was verified through structural equation modeling. The analysis results revealed that the standards-related disability issues have some influence on the standardization activities and the mediating effect by the necessity of the standard was investigated. We also found that many companies are making various efforts to overcome the barriers caused by standard activities. This suggests that a company can build a virtuous cycle structure by performing strategic actions to overcome obstacles by standardization activity and reducing the obstacles caused by standard-related research and development.

Study on Impact Properties of Polyamide 12 depending on Temperature by Selective Laser Sintering Process (선택적 레이저 소결 공정 적용 폴리아미드 12의 온도별 충격 특성에 관한 연구)

  • Kim, Moosun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.10
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    • pp.136-142
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    • 2018
  • Additive manufacturing process technology, known as the 3D printing process, is expanding its utilization from simple model realization to commercialized part production based on continuous material development. Recently, research and development have been actively carried out to fabricate lightweight and high-strength parts using polymers, such as polyamide (polyamide), which is a high-strength engineering plastic material. In this study, the Izod impact characteristics were analyzed for polyamide 12 (PA12) materials. For the specimen production, selective laser sintering process technology, which has excellent mechanical properties of finished products, was applied. In addition, PA12 and glass bead reinforced PA12 materials were produced. The specimens were classified according to the production direction on the production platform, and each specimen was subjected to an Izod test at test temperatures of $-25^{\circ}C$, $25^{\circ}C$, and $60^{\circ}C$. As a result, the impact strength of PA12 and glass bead-reinforced PA12 of vertical direction specimens were 48.8% and 16.3% lower than those of the parallel specimens at a $25^{\circ}C$ test temperature and the impact strength of parallel specimens was improved by 46.5% and 20.4% at a test temperature of $60^{\circ}C$ compared to that at $-25^{\circ}C$.

Research Trend of Soft Magnetic Composite Materials with High Energy Efficiency (고에너지효율 연자성 복합 분말 소재의 연구개발 동향)

  • Kim, Hwi-Jun
    • Journal of the Korean Magnetics Society
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    • v.21 no.2
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    • pp.77-82
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    • 2011
  • The use of soft magnetic materials have been increasing in the various industrial fields according to the increasing demand for high performance, automatic, miniaturing equipments in the recent our life. In this study, we investigated the effect of factors on the core loss and magnetic properties of electrical steel and soft magnetic composites. Furthermore, we reviewed the major efforts to reduce the core loss and improve the soft magnetic properties in the two main soft magnetic materials. Domain purification which results from reduced density of defects in cleaner electrical steels is combined with large grains to reduce hysteresis loss. The reduced thickness and the high electrical conductivity reduce the eddy current component of loss. Furthermore, the coating applied to the surface of electrical steel and texture control lead to improve high permeability and low core loss. There is an increasing interest in soft magnetic composite materials because of the demand for miniaturization of cores for power electronic applications. The SMC materials have a broad range of potential applications due to the possibility of true 3-D electromagnetic design and higher frequency operation. Grain size, sintering temperature, and the degree of porosity need to be carefully controlled in order to optimize structure-sensitive properties such as maximum permeability and low coercive force. The insulating coating on the powder particles in SMCs eliminates particle-to-particle eddy current paths hence minimizing eddy current losses, but it reduces the permeability and to a small extent the saturation magnetization. The combination of new chemical composition with optimum powder manufacturing processes will be able to result in improving the magnetic properties in soft magnetic composite materials, too.

Importance and Management of the Laboratory Notebooks in the Research Record (연구기록물 중 연구노트의 중요성과 관리 제도화)

  • Kim, Sang-Jnu
    • Journal of Information Management
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    • v.39 no.2
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    • pp.45-74
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    • 2008
  • The purpose of this study was to promote the understanding of laboratory notebook's record characteristics through getting a line on the importance of the notebooks which have record, information, communication, and proof functions. To improve the research ethics and cultures, this study was examined and investigated by literature references and survey results. This study analyzed the status of the notebooks in part of laboratory information system of the R&D institutes, paper notebooks for laboratory records management, and the introduction of ELN for digital record. For the notebook's institutionalization, more review is needed to the possibility of involvement in the conflict, evidential requisite and signature by inspector, the limitation of autonomous policy for the notebook's operation, the difficulty of preservation for 30 years, the introduction of ELN and utilization for the notebooks. To improve management and institutionalization for the notebooks, it is needed to the notebook's record for knowledge management and evidential values, support and budget for the notebook's management department, researcher's recognition conversion for the notebooks related to the intellectual property and technology transference, the record method train for the notebooks from the university classes, and the introduction of ELN related to the laboratory information management system or project management system.