• Title/Summary/Keyword: Principle component analysis

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Study on the Electromagnetic Wave Propagation In the Parallel-Plate Waveguide with the Metamaterial ENZ Tunnel Embedded (Metamaterial ENZ 터널이 포함된 평행 평판 도파관 내 전자기파의 전파 특성에 관한 연구)

  • Kahng, Sung-Tek
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.2
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    • pp.135-140
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    • 2009
  • This paper discusses how to change the electromagnetic waves' property in the cut-off causing discontinuity existing in the guiding structure of the RF passive component by using the metamaterial and elaborates on its principle. Particularly, we find and explain, from the viewpoint of electromagnetics and circuit theories, the so-called tunneling condition that when the segment with an extremely narrow cross-section leading to blockage in the parallel-plate waveguide is given the ENZ(Epsilon Near Zero) for its filling material, the wave starts to propagate through the segment. The analysis method as a transmission-line theory taking the discontinuity and material change into consideration is shown valid through the comparison with other methods for analyzing parallel-plate waveguides, and provides the illustration of the S-parameters and impedance describing the characteristics of the tunneling.

Effect of Repetitive Redox Transitions to Soil Bacterial Community and its Potential Impact on the Cycles of Iron and Arsenic (비소오염토양에서 반복적인 Redox 환경 변화가 토양 미생물 군집과 비소 및 철의 순환에 미치는 영향)

  • Park, Sujin;Kim, Sanghyun;Chung, Hyeonyong;Chang, Sun Woo;Moon, Heesun;Nam, Kyoungphile
    • Journal of Soil and Groundwater Environment
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    • v.25 no.1
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    • pp.25-36
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    • 2020
  • In a redox transition zone, geochemical reactions are facilitated by active bacteria that mediate reactions involving electrons, and arsenic (As) and iron (Fe) cycles are the major electron transfer reactions occurring at such a site. In this study, the effect of repetitive redox changes on soil bacterial community in As-contaminated soil was investigated. The results revealed that bacterial community changed actively in response to redox changes, and bacterial diversity gradually decreased as the cycle repeated. Proportion of strict aerobes and anaerobes decreased, while microaerophilic species such as Azospirillum oryzae group became the predominant species, accounting for 72.7% of the total counts after four weeks of incubation. Bacterial species capable of reducing Fe or As (e.g., Clostridium, Desulfitobacterium) belonging to diverse phylogenetic groups were detected. Indices representing richness (i.e., Chao 1) and phylogenetic diversity decreased from 1,868 and 1,926 to 848 and 1,121, respectively. Principle component analysis suggests that repetitive redox fluctuation, rather than oxic or anoxic status itself, is an important factor in determining the change of soil bacterial community, which in turn affects the cycling of As and Fe in redox transition zones.

Fast VQ Codebook Design by Sucessively Bisectioning of Principle Axis (주축의 연속적 분할을 통한 고속 벡터 양자화 코드북 설계)

  • Kang, Dae-Seong;Seo, Seok-Bae;Kim, Dai-Jin
    • Journal of KIISE:Software and Applications
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    • v.27 no.4
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    • pp.422-431
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    • 2000
  • This paper proposes a new codebook generation method, called a PCA-Based VQ, that incorporates the PCA (Principal Component Analysis) technique into VQ (Vector Quantization) codebook design. The PCA technique reduces the data dimensions by transforming input image vectors into the feature vectors. The cluster of feature vectors in the transformed domain is bisectioned into two subclusters by an optimally chosen partitioning hyperplane. We expedite the searching of the optimal partitioning hyperplane that is the most time consuming process by considering that (1) the optimal partitioning hyperplane is perpendicular to the first principal axis of the feature vectors, (2) it is located on the equilibrium point of the left and right cluster's distortions, and (3) the left and right cluster's distortions can be adjusted incrementally. This principal axis bisectioning is successively performed on the cluster whose difference of distortion between before and after bisection is the maximum among the existing clusters until the total distortion of clusters becomes as small as the desired level. Simulation results show that the proposed PCA-based VQ method is promising because its reconstruction performance is as good as that of the SOFM (Self-Organizing Feature Maps) method and its codebook generation is as fast as that of the K-means method.

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Gesture Recognition Using Zernike Moments Masked By Duel Ring (이중 링 마스크 저니키 모멘트를 이용한 손동작 인식)

  • Park, Jung-Su;Kim, Tae-Yong
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.10
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    • pp.171-180
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    • 2013
  • Generally, when we apply zernike moments value for matching, we can use those moments value obtained from projecting image information under circumscribed circle to zernike basis function. However, the problem is that the power of discrimination can be reduced because hand images include lots of overlapped information due to its special characteristic. On the other hand, when distinguishing hand poses, information in specific area of image information except for overlapped information can increase the power of discrimination. In this paper, in order to solve problems like those, we design R3 ring mask by combining image obtained from R2 ring mask, which can weight information of the power of discrimination and image obtained from R1 ring mask, which eliminate the overlapped information. The moments which are obtained by R3 ring mask decrease operational time by reducing dimension through principle component analysis. In order to confirm the superiority of the suggested method, we conducted some experiments by comparing our method to other method using seven different hand poses.

Effects of Organic Matter Application on Soil Microbial Community in a Newly Reclaimed Soil (신규 유기농경지 토양의 유기물 공급이 토양 미생물군집에 미치는 영향)

  • An, Nan-Hee;Ok, Jung-Hun;Cho, Jung-Lai;Shin, Jae-Hoon;Nam, Hong-Sik;Kim, Seok-Cheol
    • Korean Journal of Organic Agriculture
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    • v.23 no.4
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    • pp.767-779
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    • 2015
  • soil microbial activities and diversities in a newly reclaimed soil. Soil chemical properties, population of microbe, microbial biomass, and properties of microbial community were investigated under 4 different treatment (animal manure compost+green manure, chemical fertilizer, and without fertilizer). The experiment was conducted for 3 years from 2012 to 2014. The most of chemical properties in the animal manure compost+green manure treatment were increased continually compare to chemical fertilizer and without fertilizer. The population of bacteria and fungi were higher in the animal manure compost+green manure treatment, however, there was no difference on actinomyces. Soil microbial biomass C content was higher in the animal manure compost+green manure treatment than in chemical fertilizer and without fertilizer. Biolog examination showed that catabolic diversities of bacterial communities were higher in the treatment of animal manure compost+green manure. It was showed that principle component analysis of the Biolog data differentiated the organic matter amended soils from NPK and control. These results indicated that application of animal manure compost+green manure had a beneficial effect on soil microbial properties.

Sensibility Evaluation of Components of Middle and High-rise Apartment Facade in Aesthetic Old Town Districts of Kyoto - Extraction of Component Combinations Using Rough Set Theory - (쿄토시 구시가지형미관지구에서 중고층 집합주택 입면의 구성요소에 대한 감성평가 - 러프 집합을 이용한 구성요소 조합의 추출 -)

  • Shon, Dong-Hwa
    • Journal of the Korean housing association
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    • v.25 no.3
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    • pp.105-114
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    • 2014
  • Landscape zones have been designated as aesthetic old town districts across a wide range of Nakakyo-Ku and Shimokyo-Ku, city center of Kyoto, Japan. In these districts in which traditional structures and new buildings coexist, regulations of restriction on acts such as new building's heights, shapes, materials, and colors are carried out according to local governmental landscape ordinance based on Scenic Conservation Act. And yet, minimal fulfillment of the regulations according to different designer's subjective interpretation and principle of economy is rather creating abnormal shapes not harmonized with the traditional landscape. Thus, this study aims to extract combinations between form elements of middle and high rise apartment facade that affects 'harmony' and 'mismatch' in the districts by clarifying the social rules commonly implied based on intuitive judgments (sensibility evaluation) in which human experiential knowledge is involved. As research methods, the study first analyzes the form elements of the facade through a field survey, sets up a standard model through tasks of classification and segmentation and draws computer graphic images with 99 different patterns based on it. Based on these images, this study carries out sensibility evaluation and analyzes experimental data applying the rough set theory. As a result of the analysis, the combinations of form elements that affect harmony or mismatch act greatly when the colors and shapes of the pillars, positions and the patterns of the use of the first floor are combined.

Monthly Variation of n-alkanes concentration in PM2.5 of the Anmyeon Island (안면도 대기 중 PM2.5 내 n-alkanes의 월별 농도 분포 특성)

  • Kim, Ki Ae;Lee, Jong Sik;Kim, Eun Sil;Jung, Chang Hoon;Kim, Yong Pyo;Lee, Ji Yi
    • Journal of Korean Society for Atmospheric Environment
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    • v.34 no.1
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    • pp.166-176
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    • 2018
  • The n-alkanes which are stable compounds in the atmosphere are emitted by anthropogenic sources and biological sources. The goal of this study is to understand characteristics of n-alkane distributions in $PM_{2.5}$ of the Anmyeon Island which is one of background site in Korea. The concentration of n-alkanes in $PM_{2.5}$ was measured at Anmyeon Island for one year from June 2015 to May 2016. The average concentration of total n-alkanes (${\sum}$ n-alkanes) from C20 to C34 was $14.02{\pm}10.26ng\;m^{-3}$ and ranged from 1.77 to $47.65ng\;m^{-3}$. Various diagnostic parameters were used to identify the source. As a result, it is considered that Anmyeon Island had a large influence of biological sources during non-heating period, while the influence of anthropogenic emission during the heating period was significant. Principle Component Analysis (PCA) was performed and yielded three components that accounted for 93.6% of the total variance in n-alkanes. Factor 1, which accounted for 42.3% of the total variance, indicated anthropogenic source including fossil fuel and biomass combustion, while, Factor 3 was interpreted as the biological sources such as plant wax.

Selection of the high yield capacity of Hwangchil lacquer and identification of aromatic components in essential oil of Dendropanax morbifera Lev. (황칠수액 분비 우수개체 선발 및 방향성 정유성분 조사)

  • Ahn, Jun-Cheul;Kim, Min-Young;Kim, Ok-Tae;Kim, Kwang-Soo;Kim, Sung-Ho;Kim, Sea-Hyun;Hwang, Baik
    • Korean Journal of Medicinal Crop Science
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    • v.10 no.2
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    • pp.126-131
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    • 2002
  • We investigated the high yield capacity of Hwangchil lacquer for selection and identification of major aromatic components of the selected trees as well. The Hwangchil lacquer showed the difference yields by different habitat, tree ages and individual character. The selected trees showed high yield capacity of Hwangchil lacquer. We also investigated the essential oil contents and its the main components to analysis the potent of mass propagation. The major compounds were 1,6-atadiene-3-ol., ${\alpha}-terpinene,\;{\alpha}-cubebene,\;{\alpha}-ylangene,\;{\alpha}-copane,\;{\beta}-elemene,\;germacrene-D,\;{\beta}-selinene,\;{\alpha}-selinene,\;{\delta}-cadinene,{\gamma}-cardinene$, germacrene B, germacrene D-4-ol. The most principle component was germacrene D among them respectively. However, the difference of relative content ratio of each major compound was showed by individuals, population and native areas in the selected trees.

In-Situ Dry-cleaning (ISD) Monitoring of Amorphous Carbon Layer (ACL) Coated Chamber

  • Lee, Ho-Jae;Park, George O.;Hong, Sang-Jeen
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.183-183
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    • 2012
  • In the era of 45 nm or beyond technology, conventional etch mask using photoresist showed its limitation of etch mask pattern collapse as well as pattern erosion, thus hard mask in etching became necessary for precise control of etch pattern geometry. Currently available hard mask materials are amorphous carbon and polymetric materials spin-on containing carbon or silicon. Amorphous carbon layer (ACL) deposited by PECVD for etch hard mask has appeared in manufacturing, but spin-on carbon (SOC) was also suggested to alleviate concerns of particle, throughput, and cost of ownership (COO) [1]. SOC provides some benefits of reduced process steps, but it also faced with wiggling on a sidewall profile. Diamond like carbon (DLC) was also evaluated for substituting ACL, but etching selectivity of ACL was better than DLC although DLC has superior optical property [2]. Developing a novel material for pattern hard mask is very important in material research, but it is also worthwhile eliminating a potential issue to continuously develop currently existing technology. In this paper, we investigated in-situ dry-cleaning (ISD) monitoring of ACL coated process chamber. End time detection of chamber cleaning not only provides a confidence that the process chamber is being cleaned, but also contributes to minimize wait time waste (WOW). Employing Challenger 300ST, a 300mm ACL PECVD manufactured by TES, a series of experimental chamber cleaning runs was performed after several deposition processes in the deposited film thickness of $2000{\AA}$ and $5000{\AA}$. Ar Actinometry and principle component analysis (PCA) were applied to derive integrated and intuitive trace signal, and the result showed that previously operated cleaning run time can be reduced by more than 20% by employing real-time monitoring in ISD process.

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A Software Engineering Process for Safety-critical Software Application (Safety-critical 소프트웨어 적용을 위한 소프트웨어 개발 절차)

  • Kang, Byung-Heon;Kim, Hang-Bae;Chang, Hoon-Seon;Jeon, Jong-Sun;Park, Suk-Joon
    • Nuclear Engineering and Technology
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    • v.27 no.1
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    • pp.84-95
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    • 1995
  • Application of computer software to safety-critical systems is on the increase. To be successful, the software must be designed and constructed to meet the functional and performance requirements of the system. For safety reason, the software must be demonstrated not only to meet these requirements, but also to operate safely as a component within the system. For longer-term cost consideration, the software must be designed and structured to ease future maintenance and modifications. This paper present a software engineering process for the production of safety-critical software for a nuclear power plant The presentation is expository in nature of a viable high quality safety-critical software development. It is based on the ideas of a rational design process and on the experience of the adaptation of such process in the production of the safety-critical software for the Shutdown System Number Two of Wolsong 2, 3 & 4 nuclear power generation plants. This process is significantly different from a conventional process in terms of rigorous software development phases and software design techniques. The process covers documentation, design, verification and testing using mathematically precise notations and highly reviewable tabular format to specify software requirements and software design. These specifications allow rigorous, stepwise verification of software design against software requirements, and code against software design using static analysis. The software engineering process described in this paper applies the principle of information-hiding decomposition in software design using a modular design technique so that when a change is' required or an error is detected, the affected scope can be readily and confidently located. It also facilitates a sense of high degree of confidence in the ‘correctness’ of the software production, and provides a relatively simple and straightforward code implementation effort.

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