• 제목/요약/키워드: the fusion of science

검색결과 2,331건 처리시간 0.037초

Role of Radio Frequency and Microwaves in Magnetic Fusion Plasma Research

  • Park, Hyeon K.
    • Journal of electromagnetic engineering and science
    • /
    • 제17권4호
    • /
    • pp.169-177
    • /
    • 2017
  • The role of electromagnetic (EM) waves in magnetic fusion plasma-ranging from radio frequency (RF) to microwaves-has been extremely important, and understanding of EM wave propagation and related technology in this field has significantly advanced magnetic fusion plasma research. Auxiliary heating and current drive systems, aided by various forms of high-power RF and microwave sources, have contributed to achieving the required steady-state operation of plasmas with high temperatures (i.e., up to approximately 10 keV; 1 eV=10000 K) that are suitable for future fusion reactors. Here, various resonance values and cut-off characteristics of wave propagation in plasmas with a nonuniform magnetic field are used to optimize the efficiency of heating and current drive systems. In diagnostic applications, passive emissions and active sources in this frequency range are used to measure plasma parameters and dynamics; in particular, measurements of electron cyclotron emissions (ECEs) provide profile information regarding electron temperature. Recent developments in state-of-the-art 2D microwave imaging systems that measure fluctuations in electron temperature and density are largely based on ECE. The scattering process, phase delays, reflection/diffraction, and the polarization of actively launched EM waves provide us with the physics of magnetohydrodynamic instabilities and transport physics.

개발한 진단용 다엽조리개 성능평가 및 X선영상과 적외선체열영상의 융합영상 구현 (Performance Evaluation of the Developed Diagnostic Multi-Leaf Collimator and Implementation of Fusion Image of X-ray Image and Infrared Thermography Image)

  • 권순무;심재구;천권수
    • 대한방사선기술학회지:방사선기술과학
    • /
    • 제42권5호
    • /
    • pp.365-371
    • /
    • 2019
  • We have developed and applied a diagnostic Multi-Leaf Collimator (MLC) to optimized the X-ray field in medical imaging and the usefulness evaluated through the fusion of infrared image and X-ray image acquired by infrared camera. The hand and skull radiography with multi-leaf collimator(MLC) showed significant area dose reductions of 22.9% and 31.3% compared to ARC and leakage dose was compliant with KS A 4732. Also scattering doses of 50 cm and 100 cm showed a significant decrease to confirm the usefulness of MLC. It was confirmed that the fusion of infrared images with an adjustable degree of transparency was possible in the X-ray images. Therefore, fusion of anatomical information with physiological convergence is expected to contribute and improvement of diagnostic ability. In addition, the feasibility of convergence X-ray imaging and DITI devices and the possibility of driving MLC with infrared images were confirmed.

TSDnet: 적외선과 가시광선 이미지 융합을 위한 규모-3 밀도망 (TSDnet: Three-scale Dense Network for Infrared and Visible Image Fusion)

  • 장영매;이효종
    • 한국정보처리학회:학술대회논문집
    • /
    • 한국정보처리학회 2022년도 추계학술발표대회
    • /
    • pp.656-658
    • /
    • 2022
  • The purpose of infrared and visible image fusion is to integrate images of different modes with different details into a result image with rich information, which is convenient for high-level computer vision task. Considering many deep networks only work in a single scale, this paper proposes a novel image fusion based on three-scale dense network to preserve the content and key target features from the input images in the fused image. It comprises an encoder, a three-scale block, a fused strategy and a decoder, which can capture incredibly rich background details and prominent target details. The encoder is used to extract three-scale dense features from the source images for the initial image fusion. Then, a fusion strategy called l1-norm to fuse features of different scales. Finally, the fused image is reconstructed by decoding network. Compared with the existing methods, the proposed method can achieve state-of-the-art fusion performance in subjective observation.

Dominant Synoptic Patterns Controlling PM10 Spatial Variabilities over the Korean Peninsula

  • Park, Hyo-Jin;Wie, Jieun;Moon, Byung-Kwon
    • 한국지구과학회지
    • /
    • 제40권5호
    • /
    • pp.476-486
    • /
    • 2019
  • This study examines the controlling role of synoptic disturbances on $PM_{10}$ spring variability in the Korean Peninsula by using empirical orthogonal function (EOF) and back trajectory analyses. Three leading EOF modes are identified, and a lead-lag analysis suggests that $PM_{10}$ variabilities be closely related to the synoptic weather systems. The first EOF shows the spatially homogeneous distribution of $PM_{10}$, which is influenced by travelling anticyclonic disturbance with negative precipitation and descending motion. The second and third modes exhibit the dipole structures of $PM_{10}$, being associated with propagating cyclones. Furthermore, the back-trajectory analysis suggests that the transport of pollutants by anomalous winds associated with synoptic disturbances also contribute to the altered $PM_{10}$ concentration. Hence, a substantial synoptic control should be considered in order to fully understand the $PM_{10}$ spatiotemporal variability.

BMVT-M을 이용한 IR 및 SAR 융합기반 지상표적 탐지 (IR and SAR Sensor Fusion based Target Detection using BMVT-M)

  • 임윤지;김태훈;김성호;송우진;김경태;김소현
    • 제어로봇시스템학회논문지
    • /
    • 제21권11호
    • /
    • pp.1017-1026
    • /
    • 2015
  • Infrared (IR) target detection is one of the key technologies in Automatic Target Detection/Recognition (ATD/R) for military applications. However, IR sensors have limitations due to the weather sensitivity and atmospheric effects. In recent years, sensor information fusion study is an active research topic to overcome these limitations. SAR sensor is adopted to sensor fusion, because SAR is robust to various weather conditions. In this paper, a Boolean Map Visual Theory-Morphology (BMVT-M) method is proposed to detect targets in SAR and IR images. Moreover, we suggest the IR and SAR image registration and decision level fusion algorithm. The experimental results using OKTAL-SE synthetic images validate the feasibility of sensor fusion-based target detection.

Cu-Si 삽입금속을 이용한 DP강의 MIG 아크 브레이징 접합부의 미세조직과 기계적 성질 (Microstructure and Mechanical Properties of Gas Metal Arc Brazed Joint of DP Steel with Cu-Si Filler Metal)

  • 조욱제;윤태진;곽승윤;이재형;강정윤
    • Journal of Welding and Joining
    • /
    • 제34권5호
    • /
    • pp.70-76
    • /
    • 2016
  • In this study, Microstructure and tensile properties in arc brazed joints of 1000MPa grade DP steel using Cu-Si insert metal were investigated. The fusion zone was composed of Cu phase which solidified a little Fe and Si. The former phase formed due to dilute the edge of base material by arc, although Fe was not solid solution in Cu at the room temperature. Cu3Si particles formed by crystallization at $1100^{\circ}C$ during faster cooling. After the tensile shear test, there are no differences between the brazed joint efficiencies. The maximum joint efficient was about 37% compared to strength of base metal. It is better than that of arc brazed joint of DP steel using Cu-Sn filler metal. Fracture position of all brazing conditions was in the fusion zone. Crack initiation occurred at three junction point which was a stress singularity point of upper sheet, lower sheet and the fusion zone. And then crack propagated across the fusion zone. The reason why the fracture occurred at fusion zone was that the hardness of fusion zone was lower than that of base material and heat affected zone. The correlation among maximum load and hardness of fusion zone and EST at fractured position was $R^2=0.9338$. Therefore, this means that hardness and EST can have great impact on maximum load.

The art of reporter proteins in science: past, present and future applications

  • Ghim, Cheol-Min;Lee, Sung-Kuk;Takayama, Shuichi;Mitchell, Robert J.
    • BMB Reports
    • /
    • 제43권7호
    • /
    • pp.451-460
    • /
    • 2010
  • Starting with the first publication of lacZ gene fusion in 1980, reporter genes have just entered their fourth decade. Initial studies relied on the simple fusion of a promoter or gene with a particular reporter gene of interest. Such constructs were then used to determine the promoter activity under specific conditions or within a given cell or organ. Although this protocol was, and still is, very effective, current research shows a paradigm shift has occurred in the use of reporter systems. With the advent of innovative cloning and synthetic biology techniques and microfluidic/nanodroplet systems, reporter genes and their proteins are now finding themselves used in increasingly intricate and novel applications. For example, researchers have used fluorescent proteins to study biofilm formation and discovered that microchannels develop within the biofilm. Furthermore, there has recently been a "fusion" of art and science; through the construction of genetic circuits and regulatory systems, researchers are using bacteria to "paint" pictures based upon external stimuli. As such, this review will discuss the past and current trends in reporter gene applications as well as some exciting potential applications and models that are being developed based upon these remarkable proteins.

Effective Control of CH4/H2 Plasma Condition to Synthesize Graphene Nano-walls with Controlled Morphology and Structural Quality

  • Park, Hyun Jae;Shin, Jin-ha;Lee, Kang-il;Choi, Yong Sup;Song, Young Il;Suh, Su Jeong;Jung, Yong Ho
    • Applied Science and Convergence Technology
    • /
    • 제26권6호
    • /
    • pp.179-183
    • /
    • 2017
  • The direct growth method is simplified manufacturing process used to avoid damages and contaminants from the graphene transfer process. In this paper, graphene nano-walls (GNWs) were direct synthesized using electron cyclotron resonance (ECR) plasma by varying the $CH_4/H_2$ gas flow rate on the copper foil at low temperature (without substrate heater). Investigations were carried out of the changes in the morphology and characteristic of GNWs due to the relative intensity of hydrocarbon radical and molecule in the ECR plasma. The results of these investigations were then discussed.

Robust Hierarchical Data Fusion Scheme for Large-Scale Sensor Network

  • Song, Il Young
    • 센서학회지
    • /
    • 제26권1호
    • /
    • pp.1-6
    • /
    • 2017
  • The advanced driver assistant system (ADAS) requires the collection of a large amount of information including road conditions, environment, vehicle status, condition of the driver, and other useful data. In this regard, large-scale sensor networks can be an appropriate solution since they have been designed for this purpose. Recent advances in sensor network technology have enabled the management and monitoring of large-scale tasks such as the monitoring of road surface temperature on a highway. In this paper, we consider the estimation and fusion problems of the large-scale sensor networks used in the ADAS. Hierarchical fusion architecture is proposed for an arbitrary topology of the large-scale sensor network. A robust cluster estimator is proposed to achieve robustness of the network against outliers or failure of sensors. Lastly, a robust hierarchical data fusion scheme is proposed for the communication channel between the clusters and fusion center, considering the non-Gaussian channel noise, which is typical in communication systems.