• 제목/요약/키워드: WH

검색결과 855건 처리시간 0.028초

Eddy Kinetic Energy in the East Sea Estimated from Topex/Poseidon Altimeter Measurements

  • Cho Kwangwoo;Cho Kyu-Dae
    • Fisheries and Aquatic Sciences
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    • 제5권3호
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    • pp.219-228
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    • 2002
  • Based on the five-year (October 1992 through September 1997) Topex/Poseidon altimeter measurements, we describe the statistical characteristics of the eddy variability in the East Sea in terms of sea surface height anomaly, slope variability, and eddy kinetic energy (EKE). The sea surface height anomalies in the East Sea are produced with standard corrections from Topex/Poseidon measurements. In order to eliminate the high frequency noise in the sea surface height anomaly data, the alongtrack height anomaly data was filtered by about 40 km low-pass Lanczos filter based on Strub et al. (1997) and Kelly et a1. (1998). We find that there exists a distinct spatial contrast of high eddy variability in the south and low eddy energy in the north, bordering the Polar Front. In the northwestern area $(north\;of\;39^{\circ}N\;and\;west\;of\;133^{\circ}E)$ from the Polar Front where the eddies frequently appear, the EKE is also considerabel. The high kinetic energy in the southern East Sea reveals a close connection with the paths of the Tsushima Warm Current, suggesting that the high variability in the south is mainly generated by the baroclinic instability process of the Tsushima Warm Current. This finding is supported by other studies (Fu and Zlontnicki, 1989; Stammer, 1997) wh.ch have shown the strong eddy energy coupled in the major current system. The monthly variation of the EKE in both areas of high and low eddy variability shows a strong seasonality of a high eddy kinetic energy from October to February and a relatively low one from March to September. The sequential pattern of wind stress curl shows resemblance with those of monthly and seasonal EKE and the two sequences have a correlation of 0.82 and 0.67, respectively, providing an evidence that wind stress curl can be the possible forcing for the monthly and seasonal variation of the EKE in the East Sea. The seasonality of the EKE also seems to correlate with the seasonality of the Tsushima Warm Current. There also exists the large spatial and interannual variabilities in the EKE.

융합 비즈니스 모델링 프레임워크에 관한 연구 (A Study on Modeling Framework of Convergence Business)

  • 김덕현
    • 한국전자거래학회지
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    • 제17권4호
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    • pp.175-196
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    • 2012
  • 정부와 산업에서 융합 내지 융합 비즈니스에 대한 정책과 전략이 광범위하게 확산되고 있음에 반해 이를 성공적으로 구현하는데 필요한 이론적 기반과 효과적 방법론은 매우 부족한 상태이다. 특히, 융합 비즈니스 모델(BM)의 '이상적(ideal)유형' 즉, 이론적 유형에 대한 연구는 국내/외를 막론하고 아직까지 주목할 만한 결과가 없는 것으로 파악된다. 본 논문은 BM의 개념적 프레임워크로 '4W1H 모형'을 제안하고 이를 통해 융합 BM의 이론적 유형, BM 유형별 전략과 설계 수순 등을 정의할 수 있음을 보이기 위한 것이다. 4W1H 모형은 BM의 구성요소를 고객가치(why), 가치제안(what), 운영방식(how), 목표시장(whom), 공급역량(who) 등 5개로 정의한 것으로서 이를 통해 가치혁신형, 상품혁신형, 운영혁신형, 시장혁신형, 역량혁신형 등의 융합 BM 유형을 도출하였다. BM 구성요소와 유형(즉, 구조적 특성) 정의에 이어 BM 구성 요소간 상호작용(즉, 행위적 특성)에 대한 정의를 통해 BM이 기업전략과도 연계될 수 있음을 보였다.

Regions in China identification and quality control of radix Codonopsis by chemical fingerprint: Evaluation of lobetyolin from different cultivated

  • Chou, Gui X;Gao, Qiu T;Li, Jun;Duan, Ran;Cheung, Anna WH;Chu, Glanice KY;Jiang, Zhi Y;Dong, Tina TX;Tsim, Karl WK
    • Advances in Traditional Medicine
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    • 제6권4호
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    • pp.293-299
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    • 2006
  • By using high-performance liquid chromatography-photodiode array detection, a simple and accurate chromatographic fingerprint method was developed for the identification of Radix Codonopsis (roots of Codonopsis) from different sources. Eighteen herbs of Codonopsis at different habitats in China, including roots from Codonopsis pilosula, Codonopsis pilosula var. modesta and Codonopsis tangshen were analyzed by the fingerprint. The amount of lobetyolin was calibrated, which was found to be more consistent in roots of Codonopsis pilosula as compared to that of Codonopsis pilosula var. modesta and Codonopsis tangshen. Having the fingerprint results, hierarchical clustering analyses were performed to classify the eighteen herbs into three groups: Codonopsis pilosula, Codonopsis pilosula var. modesta and Codonopsis tangshen. This clustering analysis agrees very well with the pharmacognostic identification result, and which could be used as a tool in the quality control of Radix Codonopsis.

UTrustDisk: An Efficient Data Protection Scheme for Building Trusted USB Flash Disk

  • Cheng, Yong;Ma, Jun;Ren, Jiangchun;Mei, Songzhu;Wang, Zhiying
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권4호
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    • pp.2276-2291
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    • 2017
  • Data protection of removable storage devices is an important issue in information security. Unfortunately, most existing data protection mechanisms are aimed at protecting computer platform which is not suitable for ultra-low-power devices. To protect the flash disk appropriately and efficiently, we propose a trust based USB flash disk, named UTrustDisk. The data protection technologies in UTrustDisk include data authentication protocol, data confidentiality protection and data leakage prevention. Usually, the data integrity protection scheme is the bottleneck in the whole system and we accelerate it by WH universal hash function and speculative caching. The speculative caching will cache the potential hot chunks for reducing the memory bandwidth pollution. We adopt the symmetric encryption algorithm to protect data confidentiality. Before mounting the UTrustDisk, we will run a trusted virtual domain based lightweight virtual machine for preventing information leakage. Besides, we prove formally that UTrustDisk can prevent sensitive data from leaking out. Experimental results show that our scheme's average writing throughput is 44.8% higher than that of NH scheme, and 316% higher than that of SHA-1 scheme. And the success rate of speculative caching mechanism is up to 94.5% since the access pattern is usually sequential.

경쟁학습 신경망과 퍼지추론법을 이용한 움직임 분석 (Motion Analysis Using Competitive Learning Neural Network and Fuzzy Reasoning)

  • 이주한;오경환
    • 한국지능시스템학회논문지
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    • 제5권3호
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    • pp.117-127
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    • 1995
  • 본 논문에서는 ART-II 경쟁학습 신경망과 퍼지추론을 이용하여 동일한 물체를 연속적인 영상열에서 정합 시킴으로서 움직임을 분석하는 방법을 제시한다. 영상분할을 통해 얻을 수 있는 영역의 크기가 평균광도를 이용하여 영역단위의 정합을 수행하고, 영역의 모양을 표현하기 위한 특징점을 선택하기 위하여 입력패턴들의 위상을 나타날 수 있는 ART-II 경쟁학습 신경망을 사용하였다. 선택된 특징점들의 정합을 통해 각 물체에 대한 움직임 벡터를 구한다. 그러나 3차원적 실제세계의 사영인 2차원 영상은 영상 자체의 불완전성과 물체에 대한 정보를 얻기 위하여 사용되는 영상분할의 잘목스오 인한 오류 때문에 움직임 추정 과정에서 모호성이 발생한다. 이러한 움직임 분석과정에서 나타나는 불확실성을 처리하기 위하여 퍼지추론을 사용하여 신뢰도를 표현함으로써 이동 물체와 음직임 벡터를 추출하였다.

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청오경(靑烏經)의 문헌적 연구 (A philological Study on Qingwujing(靑烏經))

  • 장성규
    • 건축역사연구
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    • 제18권2호
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    • pp.27-45
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    • 2009
  • This study was to analyze the philological character of Qingwujing(靑烏經). Qingwujing is the oldest and representative documents of FengShui, especially famous for FengShui XingQi(形氣) theories. In spite of is fame, a systematic research for Qingwujing was not yet fulfilled up to now in Korea. In is the main reason why have to research the philological character of Qingwujing. The results from this research were described as following. Qingwujing(靑烏經) as knows of Qingwujing's writer is very famous already in Han 한(漢) dynasty for his accurate FengShui methods. His FengShui thories getting more powerfyl from WeiChen(魏晉) to Tang(唐) dynasty. In Tang(唐) dynasty Qingwujing was abolished by government rulers, but it recovered and retouched by some scholars from Tang(唐) and Song(宋) dynasty. In the process, the block book of Qingwujing were changed for four or five kinds. Qingwujing's block books of Ming(明) dynasty are Yimenguangdu(夷門廣牘), Xiaoshisanjing(小十三經), Jujiabibei(居家必備), and Shuofu(說郛). It's block books of Qing(淸) dynasty are Gujintushujicheng(古今圖書集成), Sikuquanshu(四庫全書), Xuejintaoyuan(學津討原), and Ershierziquanji(二十二子全集). It's block book of Choson(朝鮮) dynasty is KyujangKak(奎章閣). Among them distinctive characters been founded, but the basic contents and theories are almost same. In Korea, Qingwuzi's FengShui theories were confirmed in Silla(新羅) dynasty, and it recoreded in Soongboksa inscription written by Choi-CheeWon. Qingwu(靑烏) or Qingwuzi were known for a great FengShui master of a FengShui standing theories in Koryeo(高麗) and Choson dynasty among royal families and the aristocratic classes. And Qingwujing was a representative FengShui theory book in wh0.1ole period of Choson dynasty. Now for understanding traditional FengShui theories, we have to understand the main FengShui theories on Choson dynasty at first. For understanding Choson FengShui, the study on philological character of Qingwujing is the basic works. If those works fulfilled successfully, we can understand FengShui theories and FengShu itself more correctly.

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Volumetric Capacitance of In-Plane- and Out-of-Plane-Structured Multilayer Graphene Supercapacitors

  • Yoo, Jungjoon;Kim, Yongil;Lee, Chan-Woo;Yoon, Hana;Yoo, Seunghwan;Jeong, Hakgeun
    • Journal of Electrochemical Science and Technology
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    • 제8권3호
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    • pp.250-256
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    • 2017
  • A graphene electrode with a novel in-plane structure is proposed and successfully adopted for use in supercapacitor applications. The in-plane structure allows electrolyte ions to interact with all the graphene layers in the electrode, thereby maximizing the utilization of the electrochemical surface area. This novel structure contrasts with the conventional out-of-plane stacked structure of such supercapacitors. We herein compare the volumetric capacitances of in-plane- and out-of-plane-structured devices with reduced multi-layer graphene oxide films as electrodes. The in-plane-structured device exhibits a capacitance 2.5 times higher (i.e., $327F\;cm^{-3}$) than that of the out-of-plane-structured device, in addition to an energy density of $11.4mWh\;cm^{-3}$, which is higher than that of lithium-ion thin-film batteries and is the highest among in-plane-structured ultra-small graphene-based supercapacitors reported to date. Therefore, this study demonstrates the potential of in-plane-structured supercapacitors with high volumetric performances as ultra-small energy storage devices.

Self Charging Sulfanilic Acid Azocromotrop/Reduced Graphene Oxide Decorated Nickel Oxide/Iron Oxide Solar Supercapacitor for Energy Storage Application

  • Saha, Sanjit;Jana, Milan;Samanta, Pranab;Murmu, Naresh Chandra;Lee, Joong Hee;Kuila, Tapas
    • Composites Research
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    • 제29권4호
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    • pp.179-185
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    • 2016
  • A self-charging supercapacitor is constructed through simple integration of the energy storage and photo exited materials at the photo electrode. The large band gap of $NiO/Fe_3O_4$ heterostructure generates photo electron at the photo electrode and store the charges through redox mechanism at the counter electrode. Sulfanilic acid azocromotrop/reduced graphene oxide layer at the photo electrode trapped the photo generated hole and store the charge by forming double layer. The solar supercapacitor device is charged within 400 s up to 0.5 V and exhibited a high specific capacitance of ~908 F/g against 1.5 A/g load. The solar illuminated supercapacitor shows a high energy and power density of 33.4 Wh/kg and 385 W/kg along with a very low relaxation time of ~15 ms ensuring the utility of the self charging device in the various field of energy storage and optoelectronic application.

Development of Cobalt Sulfide-graphene Composite for Supercapacitor Applications

  • Jana, Milan;Samanta, Pranab;Murmu, Naresh Chandra;Kim, Nam Hoon;Kuila, Tapas;Lee, Joong Hee
    • Composites Research
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    • 제29권4호
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    • pp.167-172
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    • 2016
  • $Co_9S_8/reduced$ graphene (CSRG) has been prepared by a facile two step hydrothermal method and used as a supercapacitor electrode material. It is anticipated that the $Co_9S_8$ and reduced graphene oxide (RGO) would serve as a spacer material to each other to stop the agglomeration and simultaneous contribution of electrical double layer capacitance (RGO) and pseudocapacitance ($Co_9S_8$) would provide high electrochemical properties. The chemical analysis has been done by Fourier transform infrared spectroscopy and the morphology is characterised by field emission scanning electron microscopy. CSRG shows a high electrical conductivity of $98S\;m^{-1}$. The symmetric supercapacitor shows a specific capacitance of ${\sim}728F\;g^{-1}$ with a current density of $2A\;g^{-1}$. CSRG also showed an energy density of $25.2Wh\;kg^{-1}$ with a power density of $1000W\;kg^{-1}$.

Diagnosis of Graft-Versus-Host Disease after Bone Marrow Transplantation by in vivo Proton MR Spectroscopy of the Liver: Correlation with Pathologic Results

  • Cho, Soon-Gu;Lee, Moon-Hee;Suh, Chang-Hae
    • 대한자기공명의과학회:학술대회논문집
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    • 대한자기공명의과학회 2001년도 제6차 학술대회 초록집
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    • pp.135-135
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    • 2001
  • Purpose: To know the differences of the proton MR spectroscopic features of the liver between th patients with graft-versus-host disease (GVHD) and without GVHD (non-GVHD) after to marrow transplantation (BMT), and to evaluate the possibility to discriminate GVHD fro non-GVHD by analysis of the in vivo proton MR spectra. Method: We evaluated the in vivo proton MR spectra from the livers of 37 patients wh underwent BMT. Our series included 14 cases with GVHD and 23 without GVHD in the liver. Nineteen men and 18 women were included in our series. All cases of GVHD and 2 o non-GVHD were confirmed by liver biopsy and remaining of non-GVHD by evaluation clinical follow up. Proton MR spectroscopy (1H-MRS) was performed at 1.5T GE Sign Horizon (GE Medical System, Milwaukee, USA) system using localized proton STEAM sequence and body coil in all cases with subjects were located in supine position. N respiratory interruption was required during the spectroscopic signal acquisition. Paramete using in MRS were: TR = over 3000ms, TE = 30ms, number of scans = 128, voxel size = ($2{\times}2{\times}2$)$cm^3$, and one NEX. We evaluated the spectra with an attention to the differences o patterns of the peaks between GVHD and non-GVHD groups. The ratio of peak area of peaks at 1.6-4.1ppm to lipid (0.9-1.6ppm) [P(1.6-4.1ppm)/P(0.9-1.6ppm)] was calculated in GVHD and non-GVHD group, and compared the results between these groups. We als evaluated the sensitivity and specificity for discriminating GVHD from non-GVHD by anal of 1H-MRS.

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