• Title/Summary/Keyword: Layered method

Search Result 1,312, Processing Time 0.023 seconds

Magnetic Properties and Electronic Structure of $Pt_3Ni$ (001), (110) and (111) Surfaces: Density Functional Study

  • Kumar, Sharma Bharat;Kwon, O-Ryong;Odkhuu, Dorj;Hong, Soon-Cheol
    • Proceedings of the Korean Magnestics Society Conference
    • /
    • 2011.06a
    • /
    • pp.129-129
    • /
    • 2011
  • The limited understanding of the surface properties of $Pt_3Ni$ for the oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cell (PEMFC) has motivated the study of properties and electronic structures of seven layered $Pt_3Ni$ (001), (110), and (111) surfaces. The first principle method based on density functional theory (DFT) is carried out. It is found that the bulk $Pt_3Ni$ has a ferromagnetic ground state with the ordered fcc type L12 structure, which is in good agreement with other results. Non magnetic Pt has the induced magnetic moment due to the strong hybridization between 3d Ni and 5d Pt. The magnetic moment of Pt and Ni enhanced on the surface of each due to surface effect however the magnetic moment of surface Pt in the Pt-segregated Pt3Ni (111) decreased and the magnetic moment of Ni in Ni rich subsurface increased significantly. The calculated d band centers of Pt explain the possibilities for oxygen absorption and play the important roles in altering the catalytic properties. The spin polarized densities of states are presented in order to understand physical properties of Pt in different surfaces in detail.

  • PDF

Optimization of Lithium in Li1+x[Mn0.720Ni0.175Co0.105]O2 as a Cathode Material for Lithium Ion Battery

  • Kim, Jeong-Min;Jeong, Ji-Hwa;Jin, Bong-Soo;Kim, Hyun-Soo
    • Journal of Electrochemical Science and Technology
    • /
    • v.2 no.2
    • /
    • pp.97-102
    • /
    • 2011
  • Different amounts of excess lithium in the range of x = 0~0.3 were added to $Li_{1+x}[Mn_{0.720}Ni_{0.175}Co_{0.105}]O_2$ cathode materials synthesized using the co-precipitation method to investigate its microstructure and electrochemical properties. Pure layered structure without impurities was confirmed in the XRD pattern analysis and increasing peak intensity of $Li_2MnO_3$ was observed along with the addition of over 0.2 mol Li. The initial discharge capacity of the stoichiometric composition was determined to be 246 mAh/g, while the discharge capacity of the addition of 0.1 mol Li was obtained to be 241 mAh/g, which was not significantly different from that of the stoichiometric composition. However, the discharge capacities decreased dramatically after the addition of 0.2 and 0.3 mol Li to 162 mAh/g and 146 mAh/g, respectively. In the rate capability test, the active $Li_{1+x}[Mn_{0.720}Ni_{0.175}Co_{0.105}]O_2$ cathode material of the stoichiometric composition showed a dramatic decrease in its discharge capacity with increasing C-rate, as evidenced by the result that the discharge capacity at 5C was 13% compared with 0.1C. On the other hand, the discharge capacity of compositions containing excess lithium was improved at higher current rates. The cycling test showed that the composition containing an excess of 0.1 mol Li had the most outstanding capacity retention.

Study of Microwave Propagation Characteristics of Matching Liquids for the Microwave Cancer Detection System (유방암 진단 시스템을 위한 정합 액체의 전파 특성에 관한 연구)

  • Kim, Jang-Yeol;Minz, Laxmikant;Lee, Kwang-Jae;Son, Seong-Ho;Jeon, Soon-Ik
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.25 no.4
    • /
    • pp.442-450
    • /
    • 2014
  • This paper is a study of the propagation characteristic of matching liquids in the skin-covered breast model. In order to evaluate the matching liquids, we investigated six kinds of matching liquids applied to proposed 1-D breast model from frequency range of 3~6 GHz. A uniform plane wave is projected / transmitted inside the multi-layered breast model. Then the propagation characteristics inside the model and the transmission loss of each matching liquids were analyzed. The studying method presented in the paper can be used in the breast cancer detection system, the field of cancer detection using human tissue and the field of other medical devices. This paper was applied to the breast cancer detection system. Consequently, these studies could be used to determine the suitable type of matching liquids for breast cancer detection system and to apply useful for performance analysis.

An implementation of the mixed type character recognition system using combNET (CombNET 신경망을 이용한 혼용 문서 인식 시스템의 구현)

  • 최재혁;손영우;남궁재찬
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.21 no.12
    • /
    • pp.3265-3276
    • /
    • 1996
  • The studies of document recongnition have been focused mainly on Korean documents. But most of documents composed of Korean and other characters. So, in this paper, we propose the document recognition system that can recognize the multi-size, multi font and mixed type characters. We have utilized a large scale network model, "CombNET" which consists of a 4 layered network with combstructure. And we propose recognition method that can recognize characters without discrimination of character type. The first layer constitutes a Kohonen's SOFM network which quantizes an input feature vector space into several sub-spaces and the following 2-4 layers constitutes BP network modules which classify input data in each sub-space into specified catagories. An experimental result demonstrated the usefulness of this approach with the recognition rates of 95.6% for the training data. For the mixed type character documents we obtained the recognition rates of 92.6% and recognition speed of 10.3 characters per second.

  • PDF

Study on Virtual Fashion Coordination to Realize Magic Mirror -Focus on RFID Code Proposal- (매직미러 실현을 위한 가상 패션코디네이션 연구 -RFID 코드 제안 중심으로-)

  • Lee, Woon-Young
    • Journal of the Korean Society of Costume
    • /
    • v.56 no.8 s.108
    • /
    • pp.83-94
    • /
    • 2006
  • In this era of ubiquitous service, a computing device has functions similar with human beings. It influences all major fields of human life, such as clothing, dieting and housing. In order to use the coordination functions of the magic mirror, which might be a basic part of clothing in the era of ubiquitous service, this study concentrates on product information that should be inputted in RFID chip in detail in order to exercise virtual fashion coordination. Information should be inputted in RFID chip to use magic mirror for fashion coordination, a direction for doing this was also suggested. After coding the suggested clothing items, virtual fashion coordination was implemented as a fashion illustration. This study is as following, First, sorts standard code for suitable coordination in 4 images and presented to a proof. Code denoted by 10 characters. Each code literal special quality marks by two characters and divided by season, image, fabric, item, rotor, five items. Item middle of characters of 10 code, when agree on article more than 8, coordination is enabled. Secondely, It is presented by coordination to dressing action picture by suitable coordination classified apart in whole occasions, and coordination method by wearer inclination is remembered wearer's dressing action picture to Magic mirror including layered look. Thirdly, wardrobe of Magic mirror clothes that always buy newly in magic mirror, is washing and clothes that do not take to wardrobe did to be controlled. Fourth, Wealth and schedule is suggested firster than wearer's dressing action.

Characteristics of Eco-friendly Design Expressed in Issey Miyake's Fashion (이세이 미야케의 패션에 표현된 친환경적 디자인 특성)

  • Ha, Seung-Yeon;Lee, Yun-Hee
    • Journal of the Korean Society of Costume
    • /
    • v.62 no.3
    • /
    • pp.57-72
    • /
    • 2012
  • Interest in the environment is rising in all the sectors of industry and culture. Even in the fashion industry, fashion designers have recently begun delivering messages on the environment. In particular, $Issey$ $Miyake$ has been constantly interested in environmental issues, and has been deemed as a designer who values practicality and universality in clothing. This study seeks to examine Issey Miyake's fashion from the perspective of an eco-friendly design. This research analyzed collections of $Issey$ $Miyake$ from 1980 to 2010 through photo works and www.firstview.com. The research method was to study 8 people who have professionalism in fashion design and have analyzed 201 works of $Issey$ $Miyake$ from 1980s to 2000s that have the characteristics of eco-friendly design. The results showed the following characteristics of eco-friendly design in Issey Miyake's fashion : naturality, simplicity, sustainability and transformability. First, $Issey$ $Miyake$ preferred natural materials and used Japan traditional dyeing that integrated modern techniques for naturality. Second, he expressed simplicity in his fashion by applying the least cutting and sewing in geometric panels. Third, he pursued sustainability with comfortable clothing that anyone could wear regardless of trend, age and body shape. Finally, he developed the A-POC system that eliminated the usual needs for cutting and sewing and tried transformability on clothing using buttons, strings, belts, zippers, and layered styling.

A Study on the Characteristics of Mediation in Fashion Culture Contents Found in Transmedia - Focusing on Modern Fashion since the 20th Century - (트랜스미디어에 나타난 패션 문화 콘텐츠의 매개특성 연구 - 20세기 이후 현대 패션사를 중심으로 -)

  • Kim, Hyangja
    • Journal of the Korean Society of Costume
    • /
    • v.67 no.4
    • /
    • pp.131-152
    • /
    • 2017
  • The purpose of this study is to analyze modern fashion culture in the 20th century through changes in transmedia in order to better understand characteristics of fashion contents. The study also strived to identify the characteristics of remediation in modern fashion and media by exploring the cultural code, and use it to establish an integrated view. The subjects and the method of the study are as follows. First, the study analyzed the development of transmedia and fashion culture since the 20th century. Second, it identified the transitional characteristics of transmedia. Third, the study analyzed the characteristics of remediation in modern fashion culture by using the characteristics of mediation, which appeared with the transitional characteristics of transmedia. The study results are as follows. First, the types of remediation are 'borrowing,' 'Representation,' 'Expansion,' 'Refashion,' and 'Absorb.' In old and new media, each type can be aesthetically experienced in 'transparency,' opaqueness,' 'Hypermediacy,' and 'Immediacy.' Second, fashion culture can undergo a transformation from its original form to a second and a third iteration, and this process allows for possibility of an expansion of multiple plots and well-rounded character settings. This opens up the possibility for fashion consumer participation, and signifies a transition into an environment where expansion of time and space is possible. The third finding is the non-mediation of fashion objects. The mediating relationship between clothes and media is directly connected to the development of new media. The immersion of new media by fashion consumers has the characteristics of 'transparency'/'Non-mediation,' and the reinterpretation and reproduction of original fashion styles have the characteristics of 'opaqueness'/'Hyper-mediation.' Fourth, fashion culture has data variability. Through 'Borrowing,' 'Representation,' 'Expansion,' 'Remodeling,' and 'Absorption,' the cultural hierarchy of reproduced fashion forms a multi-layered integrated network. Mediation code, which repurposes fashion culture contents, also creates new media fashion through transmedia.

Scale Effects of Stability Parameters in the Hydraulic Model Tests of Rubble Mound Coastal Structures (사석구조물(捨石構造物)의 안정성(安定性)에 관한 수리모형(水理模型)의 축척효과(縮尺効果))

  • Ryu, Cheong Ro
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.7 no.3
    • /
    • pp.111-119
    • /
    • 1987
  • Scale effects of stability, run-up, run-down and reflection of layered coastal structures are investigated through the experiments with 7 kinds of hydraulic scale models. The occurrence mechanism and the control method of scale effects are also discussed. As a result, it is found that the similarity of permeability of inner layers plays an important role in the occurrence of scale effects, which has been neglected in the most of conventional model tests. To assure the best scale effects for permeable coastal structures, control of Reynolds numbers of the porous media flow in each layer is recommended. It is also found that Reynolds numbers in revetment, filter, and core layer must be greater than $2{\times}10^4$, $3{\times}10^3$, and $1{\times}10^3$, respectively.

  • PDF

Sound-Insulation Design of Aluminum Extruded Panel in Next-Generation High-Speed Train (차세대 고속철도 차량용 알루미늄 압출재의 차음 설계)

  • Kim, Seock-Hyun;Seo, Tae-Gun;Kim, Jeong-Tae;Song, Dal-Ho
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.35 no.5
    • /
    • pp.567-574
    • /
    • 2011
  • Aluminum extruded panels are widely used instead of corrugated steel panels for weight reduction in high-speed trains. Of the layers in the train body, it makes the largest contribution to the sound insulation. However, compared with that of a flat panel with the same weight, the TL of the aluminum extruded panel is remarkably lower in the local resonance frequency band. We study aluminum extruded panels for next-generation 400-km/h trains. We investigate the problem of sound insulation and propose a practical method to improve the sound-insulation performance. The local resonance frequency region is increased by a modification of the core structure, and urethane foam is placed in the core. The effect on the sound insulation is verified by experiments. Finally, the improvement for the entire sound-transmission loss is estimated for the layered floor panels of express trains.

Protection of Location Privacy for Spatio-Temporal Query Processing Using R-Trees (R-트리를 활용한 시공간 질의 처리의 위치 개인정보 보호 기법)

  • Kwon, Dong-Seop
    • The Journal of Society for e-Business Studies
    • /
    • v.15 no.3
    • /
    • pp.85-98
    • /
    • 2010
  • The prevailing infrastructure of ubiquitous computing paradigm on the one hand making significant development for integrating technology in the daily life but on the other hand raising concerns for privacy and confidentiality. This research presents a new privacy-preserving spatio-temporal query processing technique, in which location based services (LBS) can be serviced without revealing specific locations of private users. Existing location cloaking techniques are based on a grid-based structures such as a Quad-tree and a multi-layered grid. Grid-based approaches can suffer a deterioration of the quality in query results since they are based on pre-defined size of grids which cannot be adapted for variations of data distributions. Instead of using a grid, we propose a location-cloaking algorithm which uses the R-tree, a widely adopted spatio-temporal index structure. The proposed algorithm uses the MBRs of leaf nodes as the cloaked locations of users, since each leaf node guarantees having not less than a certain number of objects. Experimental results show the superiority of the proposed method.