• Title/Summary/Keyword: Cross-domain

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Time-Domain Modeling of Wavelength Conversion in Semiconductor Optical Amplifier Directional Coupler (반도체 광증폭기로 형성된 방향성결합기에서 파장 변환에 대한 시영역 모델링)

  • 정호연;정영철
    • Proceedings of the Optical Society of Korea Conference
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    • 2000.08a
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    • pp.24-25
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    • 2000
  • 파장변환 소자는 최근에 급격히 발전하는 광네트웍을 구축하기 위하여 필수적인 소자로서 여러 가지 형태에 대한 연구개발이 진행되고 있다. 그중에서도, 최근에는 반도체 광증폭기로 형성된 방향성 결합기구조(semiconductor optical amplifier directional coupler)에서의 상호 이득 포화(XPM : cross-phase modulation)에 의한 파장변환에 대한 개념이 제안되고 가능성이 실험적으로 입증된 바 있다. 이런 구조의 파장변환 소자는 입력 광신호의 파워가 작을때는 위상 정합이 되어 반도체 광증폭기의 광모드가 완전히 결합되어 cross state로 변환된 파장의 광파워가 많이 출력되고, 신호 입력 파워가 증가함에 따라 결합이 감소하게 되어 Cross state에서의 출력 파워는 감소하게 된다. 이와 같은 소자는 입력 신호광과 변환된 신호광이 역방향으로 진행하는 경우 광필터가 필요없이 파장변환이 가능하고, 변환 후의 소광비가 향상되기 때문에 향후 다양한 형태로 응용될 가능성이 있으며, 적정 설계 및 성능 예측을 위해서는 시영역에서 모델링할 수 있는 방법론을 구축하는 것이 필요하다. 본 논문에서는 연산자 분리 방법$^{(1)}$ 을 적용하여 상술한 파장변환기를 해석하기에 적당하도록 시영역 동적 모델을 구현하고, 파장변환 특성을 여러 가지 면에서 분석하여 보았다. (중략)

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Investigation of Typhoon Wind Speed Records on Top of a Group of Buildings

  • Liu, Min;Hui, Yi;Li, Zhengnong;Yuan, Ding
    • International Journal of High-Rise Buildings
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    • v.8 no.4
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    • pp.313-324
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    • 2019
  • This paper presents the analysis of wind speeds data measured on top of three neighboring high-rise buildings close to a beach in Xiamen city, China, during Typhoon "Usagi" 2013. Wind tunnel simulation was carried out to validate the field measurement results. Turbulence intensity, turbulence integral scale, power spectrum and cross correlation of recorded wind speed were studied in details. The low frequency trend component of the typhoon speed was also discussed. The field measurement results show turbulence intensity has strong dependence to the wind speed, upwind terrain and even the relative location to the Typhoon center. The low frequency fluctuation could severely affect the characteristics of wind. Cross correlation of the measured wind speeds on different buildings also showed some dependence on the upwind terrain roughness. After typhoon made landfall, the spatial correlation of wind speeds became weak with the coherence attenuating quickly in frequency domain.

Measurement of the Skin Blood Flow using Cross-Correlation (Cross-Correlation법에 의한 피부 혈류속도 측정)

  • Lee, Jeong-Taek;Im, Chun-Seong;Ryu, Jeom-Su;Lee, Jong-Su;Gong, Seong-Bae;Kim, Yeong-Gil
    • Journal of Biomedical Engineering Research
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    • v.19 no.4
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    • pp.379-384
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    • 1998
  • To measure precisely the blood velocity in the skin microcirculation, we have used time domain correlation (called Cross-Correlation) based on the processing of the backscattered RF signal obtained with a wideband echographic imaging transducer, although it is difficulties of adaptation of the pulsed wave system, because of the data processing in real time and the hardware problem. This dedicated technology based on a 20MHz echographic imaging system has been developed. We present how the experimental data, i.e. the backscattered RF signal, have to be analyzed. After RF lines realignment, stationary echo canceling procedure and correlation level control, a velocity profile has been obtained. In-vitro result show that velocity measurements as low as 0.1mm/sec attainable with a 80${\mu}m$ in axial resolution. We have also validated with in-vivo experimentation on the external ear of a rabbit using B-mode sector scanning image and M-mode image of a custom made 20MHz skin image system. The flow of the "auriculares caudales" vein, a microvessel of 600 m diameter, has been detected and studied. This technique will allow a more precise exploration of circulatory troubles in cutaneous pathologies.

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Measurement of the Propagation Constant of a Power Cable Using a Two-Port Time-Domain Reflectometry Technique (Two-Port Time Domain Reflectometry 방법을 이용한 XLPE 전력용 케이블의 전파 특성 측정)

  • Shin, Dong Sik;Cho, Hyeon Dong;Park, Wee Sang;Yi, Sang-Hwa;Sun, Jong-Ho
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.24 no.3
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    • pp.310-315
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    • 2013
  • This paper presents a two-port time-domain reflectometry(TDR) measurement technique for extracting the complex propagation constant of a cross-linked polyethylene(XLPE) cable. For the extraction, a short pulse transmitted through the cable is measured in the time domain and analyzed in the frequency domain. The propagation constant of a 22.9 kV XLPE cable with a conductor area of 325 $mm^2$ is extracted up to a frequency of approximately 2.14 GHz. The $S_{21}$ measured using a network analyzer and the two-port TDR technique are compared for verification. As a result compared with previous TDR method, the upper possible frequency limit for extracting the propagation constant increases and the measurement error decreases.

A Blockchain-enabled Multi-domain DDoS Collaborative Defense Mechanism

  • Huifen Feng;Ying Liu;Xincheng Yan;Na Zhou;Zhihong Jiang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.3
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    • pp.916-937
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    • 2023
  • Most of the existing Distributed Denial-of-Service mitigation schemes in Software-Defined Networking are only implemented in the network domain managed by a single controller. In fact, the zombies for attackers to launch large-scale DDoS attacks are actually not in the same network domain. Therefore, abnormal traffic of DDoS attack will affect multiple paths and network domains. A single defense method is difficult to deal with large-scale DDoS attacks. The cooperative defense of multiple domains becomes an important means to effectively solve cross-domain DDoS attacks. We propose an efficient multi-domain DDoS cooperative defense mechanism by integrating blockchain and SDN architecture. It includes attack traceability, inter-domain information sharing and attack mitigation. In order to reduce the length of the marking path and shorten the traceability time, we propose an AS-level packet traceability method called ASPM. We propose an information sharing method across multiple domains based on blockchain and smart contract. It effectively solves the impact of DDoS illegal traffic on multiple domains. According to the traceability results, we designed a DDoS attack mitigation method by replacing the ACL list with the IP address black/gray list. The experimental results show that our ASPM traceability method requires less data packets, high traceability precision and low overhead. And blockchain-based inter-domain sharing scheme has low cost, high scalability and high security. Attack mitigation measures can prevent illegal data flow in a timely and efficient manner.

효모시스템에서 Human Transglutaminase C(TGase II)의 발현에 관한 연구 : C-말단부위의 결손효과

  • Woo, Sang-Kyu;Jung, Sun-Mi;Rhee, Sang-Ki;Ahn, Byeong-Yoon;Kim, Hee-Chul
    • Microbiology and Biotechnology Letters
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    • v.24 no.3
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    • pp.290-298
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    • 1996
  • In an effort to understand the role of the conserved domain and of the heterologous one-third part of the carboxy terminal domain of transglutaminase C (TGase II), attempts were made to express TGase II cDNA of human origin in yeast Saccharomyces cerevisiae as in a full-length form as well as in a form of C-terminal truncation. The 2$\mu$-based expression plasmids which contained the TGase II cDNA under the gal inducible promoter were introduced into yeast and the maintenance of the full-length and truncated form of the TGase II gene plasmids were confirmed by Southern blot. The expression of the TGase II gene was analysed by reverse transcription polymerase chain reaction (RT-PCR), and western blot analyses. As assayed by [1,4$^{14}$C]-putrescine incorporation into succinylated casein, the full-lenth as well as the truncated forms of recombinant TGase II showed some catalytic activity. These results indicate that the N-terminal homologous domain of human TGase II retains a catalytically active domain. The level of TGase II expressed in yeast, however, was far lower than satisfactory and other expression system should be sought further chracterization of the enzyme. The negative effect of TGase II on the growth of yeast is interesting with respect to the physiological effect of TGase II in cornification of epidermal keratinocytes.

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Development and Application of Protein-Protein interaction Prediction System, PreDIN (Prediction-oriented Database of Interaction Network)

  • 서정근
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2002.06a
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    • pp.5-23
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    • 2002
  • Motivation: Protein-protein interaction plays a critical role in the biological processes. The identification of interacting proteins by bioinformatical methods can provide new lead In the functional studies of uncharacterized proteins without performing extensive experiments. Results: Protein-protein interactions are predicted by a computational algorithm based on the weighted scoring system for domain interactions between interacting protein pairs. Here we propose potential interaction domain (PID) pairs can be extracted from a data set of experimentally identified interacting protein pairs. where one protein contains a domain and its interacting protein contains the other. Every combinations of PID are summarized in a matrix table termed the PID matrix, and this matrix has proposed to be used for prediction of interactions. The database of interacting proteins (DIP) has used as a source of interacting protein pairs and InterPro, an integrated database of protein families, domains and functional sites, has used for defining domains in interacting pairs. A statistical scoring system. named "PID matrix score" has designed and applied as a measure of interaction probability between domains. Cross-validation has been performed with subsets of DIP data to evaluate the prediction accuracy of PID matrix. The prediction system gives about 50% of sensitivity and 98% of specificity, Based on the PID matrix, we develop a system providing several interaction information-finding services in the Internet. The system, named PreDIN (Prediction-oriented Database of Interaction Network) provides interacting domain finding services and interacting protein finding services. It is demonstrated that mapping of the genome-wide interaction network can be achieved by using the PreDIN system. This system can be also used as a new tool for functional prediction of unknown proteins.

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Comparison of Quality of Life of Autologous and Allogeneic Hematopoietic Stem Cell Transplantation Recipients (자가 조혈모세포 이식환자와 동종 조혈모세포 이식환자의 삶의 질의 비교)

  • Kim, Eun-Ji
    • Asian Oncology Nursing
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    • v.8 no.1
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    • pp.50-60
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    • 2008
  • Purpose: The purpose of this study was to compare Quality of life (QOL) in type and time after Hematopoietic stem cell tansplantation (HSCT) for patients with hematologic cancer. Method: This study was cross-sectional. The autologous recipients was 120, the allogeneic recipients was 237. The obtained data were analyzed using T-test, One-way ANOVA, Scheffe's test. Results: No significant differences were total QOL between the autologous and allogeneic recipients. But the autologous recipients reported better status than the allogeneic recipients in physical domain, especially 1-3 yr after HSCT. There was poorer QOL of 1-3 yr compared to 1 yr after HSCT in physical, psychological and social domain between the two groups. QOL in time after HSCT of the autologous recipients was significance differences in psychological, social domain. And QOL in time after HSCT of the allogeneic recipients was significant differences in physical, psychological and social domain. Conclusions: QOL of recipients undergoing HSCT is recovered beyond 3 yr point. Accordingly, long term care and service is essential to recipients undergoing HSCT. And further studies with a longitudinal design are necessary.

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The Relationship between Health Education Competency and Satisfaction of Professional Nursing in Nursing Students (간호학생의 보건교육 수행정도와 간호전문직 만족도와의 관계연구)

  • Ju He-Kyoung
    • The Journal of Korean Academic Society of Nursing Education
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    • v.5 no.1
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    • pp.106-117
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    • 1999
  • A study was conducted to identify the perceptions about health education competence and satisfaction of nursing profession, and the relationship between health education competency and satisfaction of nursing profession in nursing students. The subjects were 118 nursing students who were third year at a diploma course. The results of this study are as follows : 1) In domain of health education process, the highest level of competency was the need assessment of the individual health education(mean : 3.62) and the lowest level of competency was the evaluation of heath education program(mean : 2.93. 2) In domain of health education method, the level of competency was estimated ordered as counselling and interview (mean : 3.53), health campaign(mean : 3.42), demonstration(mean : 3.30), role play (mean : 3.28), group discussion (mean : 3.25), lecture(mean : 3.10). 3) In domain of health education place, the level of competency was estimated ordered as of patient education while giving individually care(mean : 3.68), at home(mean : 3.67), in the classrom(mean : 3.67), in the community(mean : 3.35), while teaching with group patients at hosital(mean : 3.30). 4) In domain of activities of health educator, the level of competency was ordered as collaborator(mean : 3.59), coordinator(mean : 3.31), material developer(mean 3.14), program evaluator(mean : 3.13), program designer(mean 3.10). 5) Health education competency was found to be significantly related to satisfaction of professional nursing.

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A Domain Analysis on the Hybrid of Fashion Trends - Fashion Trends of 1995 S/S $\sim$ 2001/2002 A/W - (패션 트렌드의 다중화(多重化) 현상(現象)에 대(對)한 범주(範疇) 분석(分析) - 1995 S/S$\sim$2001/2002 A/W 시즌을 중심(中心)으로 -)

  • Yun, Su-Jeong;Lee, Joo-Hyeon
    • Journal of Fashion Business
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    • v.6 no.2
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    • pp.110-123
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    • 2002
  • This study investigated the influence of cultural and general trend of the times on fashion trends and the hybridization of these trends. The objectives of this study were to suggest new approach method of the fashion forecasting and to find out the cultural meanings and values of fashion. Key words that explains fashion trend from spring/summer of 1995 to fall/winter of 2002 were collected from professional fashion trend journals. These terms were analysed with domain analysis based on the semantic relationship. The frequency of their appearance in each season and the aspect of their appearance in each season were analysed. The hybrids of the fashion trends were analysed longitudinally and cross-sectionally as well by investigating the cover terms that were found as a result of domain analysis. The method used in this study can be applied to future study of fashion trend in that it offers an objective view of fashion trend and can allow researchers to study fashion trend in a concrete way.