• Title/Summary/Keyword: validity regions

Search Result 177, Processing Time 0.027 seconds

VALIDITY REGIONS OF THEORETICAL MODELS FOR ESTIMATING THE RCS OF LOSSY DIELECTRIC CYLINDERS

  • Hong, Jin-Young;Kwon, Soon-Gu;Oh, Yi-Sok
    • Proceedings of the KSRS Conference
    • /
    • 2007.10a
    • /
    • pp.369-373
    • /
    • 2007
  • This paper presents an examination of theoretical scattering models for radar cross sections (RCS) of lossy dielectric cylinders, such as exact analytical solution, low frequency approximation (Rayleigh) and high frequency approximation (Physical Optics). The validity regions of the PO and Rayleigh models are closely examined with exact solution in terms of various wavelengths and dielectric constants of a circular cylinder. And also this paper examines the PO and Rayleigh models for back and forward scatter RCS of a cylinder at various incidence angles and polarizations. It was found that the PO and Rayleigh model have their validity regions for estimating the RCS of a circular cylinder.

  • PDF

Suppression of Discontinuity in the Pseudoscopic Region of Multiview 3D Displays

  • Lee, Jae-Yong;Miyashita, Tetsuya;Uchida, Tatsuo
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2009.10a
    • /
    • pp.1107-1111
    • /
    • 2009
  • Flat panel multiview 3D displays developed in recent years have pseudoscopic regions that appear unnatural to viewers. We suggest a new method to suppress the pseudoscopic regions based on the visual characteristics of binocular rivalry. We confirm the validity of this method experimentally and show that the unnaturalness caused by pseudoscopic regions can be effectively suppressed.

  • PDF

Surface Wind Regionalization Based on Similarity of Time-series Wind Vectors

  • Kim, Jinsol;Kim, Hyun-Goo;Park, Hyeong-Dong
    • Asian Journal of Atmospheric Environment
    • /
    • v.10 no.2
    • /
    • pp.80-89
    • /
    • 2016
  • In the complex terrain where local wind systems are formed, accurate understanding of regional wind variability is required for wind resource assessment. In this paper, cluster analysis based on the similarity of time-series wind vector was applied to classify wind regions with similar wind characteristics and the meteorological validity of regionalization method was evaluated. Wind regions in Jeju Island and Busan were classified using the wind resource map of Korea created by a mesoscale numerical weather prediction modeling. The evaluation was performed by comparing wind speed, wind direction, and wind variability of each wind region. Wind characteristics, such as mean wind speed and prevailing wind direction, in the same wind region were similar and wind characteristics in different wind regions were meteor-statistically distinct. It was able to identify a singular wind region at the top area of Mt. Halla using the inconsistency of wind direction variability. Furthermore, it was found that the regionalization results correspond with the topographic features of Jeju Island and Busan, showing the validity.

Proposal of Modified Correlation to Calculate the Horizontal Global Solar Irradiance for non-Measuring Cloud-cover Regions (운량 비측정 지역을 위한 수평면전일사량 예측 상관식의 수정모델 제안)

  • Cho, Min-Cheol;Kim, Jeongbae
    • Journal of Institute of Convergence Technology
    • /
    • v.6 no.2
    • /
    • pp.29-33
    • /
    • 2016
  • Recently, the authors of this paper proposed newly the correlation model to calculate the horizontal global solar radiation in Korea based the Zhang-Huang (ZH) model proposed in 2002 for China. Previous study was pronounced the correlation with a new term of the duration of sunshine proved as being closely related with the hourly solar radiation in Korea into ZH model. And then another modified correlation for the regions without measuring cloud cover was proposed and evaluated the accuracy and validity for those regions. So, this study was performed to propose modified correlation to calculate the horizontal global solar irradiance of non-measuring cloud-cover regions. Finally, this study proposed the new correlation that could well predict hourly and daily total solar radiation for all regions, various seasons, and various weather conditions including overcast and clear, with higher accuracy and lower error than other models proposed ever before in Korea for non-measuring cloud-cover regions.

Electrical Detection of Ear Acupuncture Points and Musculoskeletal Pain (경혈탐측기에 반응한 이혈(耳穴)과 신체 동통 부위와의 관계 연구)

  • Kang, Mun-Su;Park, Hyun-Chul;Kim, Lak-Hyung;Yu, Jeong-Suk;Song, Beom-Yong
    • Journal of Acupuncture Research
    • /
    • v.24 no.6
    • /
    • pp.187-193
    • /
    • 2007
  • Objectives : The objectives of this study were to investigate the relationship between electrical detection of ear acupuncture points and musculoskeletal pain. Methods : 18 adults who have musculoskeletal pain without trauma factorsparticipated in this study. They answered the questionnaire and their ear acupuncture points were examined with electrical detectors. We analyzed the relationship between electrical detection of ear acupuncture points and musculoskeletal pain with concordance rate and validity. Results : Total concordance rates of the head region was 68.00%(questionnaire) 32.08%(investigation), that of vertebral region was 67.86%, 59.38%, that of both upper limbs was 86.67%, 39.69%, and that of both lower limbs was 50.00%, 23.46%. The true positive rate was 0.704, the true negative rate was 0.492, the false positive rate was 0.508, and the false negative rate was 0.296 in the validity test. In the head, two concordance rates of the temporal and occipital regions were relatively higher than those of the parietal and frontal regions. In the vertebral region, two concordance rates of the cervical and lumbar regions were relatively higher than those of the thoracic and sacrum regions. In the upper limb, two concordance rates of the shoulder and shoulder joints were relatively higher than those of the others. In the lower limb, concordance rates of investigation were relatively low at all areas. The right lower limb was relatively higher than the left in concordance rates of the questionnaire. Conclusions : The results suggest that electrical detection of ear acupuncture points can be used in the diagnosis and treatment of musculoskeletal pain.

  • PDF

Synaptic Plasticity in Mouse Models of Autism Spectrum Disorders

  • Chung, Leeyup;Bey, Alexandra L.;Jiang, Yong-Hui
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.16 no.6
    • /
    • pp.369-378
    • /
    • 2012
  • Analysis of synaptic plasticity together with behavioral and molecular studies have become a popular approach to model autism spectrum disorders in order to gain insight into the pathosphysiological mechanisms and to find therapeutic targets. Abnormalities of specific types of synaptic plasticity have been revealed in numerous genetically modified mice that have molecular construct validity to human autism spectrum disorders. Constrained by the feasibility of technique, the common regions analyzed in most studies are hippocampus and visual cortex. The relevance of the synaptic defects in these regions to the behavioral abnormalities of autistic like behaviors is still a subject of debate. Because the exact regions or circuits responsible for the core features of autistic behaviors in humans are still poorly understood, investigation using region-specific conditional mutant mice may help to provide the insight into the neuroanatomical basis of autism in the future.

Text Detection in Scene Images Based on Interest Points

  • Nguyen, Minh Hieu;Lee, Gueesang
    • Journal of Information Processing Systems
    • /
    • v.11 no.4
    • /
    • pp.528-537
    • /
    • 2015
  • Text in images is one of the most important cues for understanding a scene. In this paper, we propose a novel approach based on interest points to localize text in natural scene images. The main ideas of this approach are as follows: first we used interest point detection techniques, which extract the corner points of characters and center points of edge connected components, to select candidate regions. Second, these candidate regions were verified by using tensor voting, which is capable of extracting perceptual structures from noisy data. Finally, area, orientation, and aspect ratio were used to filter out non-text regions. The proposed method was tested on the ICDAR 2003 dataset and images of wine labels. The experiment results show the validity of this approach.

A Method for Text Detection and Enhancement using Spatio-Temporal Information (시공간 정보를 이용한 자막 탐지 및 향상 기법)

  • Jeong, Jong-Myeon
    • Journal of the Korea Society of Computer and Information
    • /
    • v.14 no.8
    • /
    • pp.43-50
    • /
    • 2009
  • Text information in a digital video provides crucial information to acquire semantic information of the video. In the proposed method. text candidate regions are extracted from input sequence by using characteristics of stroke and text candidate regions are localized by using projection to produce text bounding boxes. Bounding boxes containing text regions are verified geometrically and each bounding box existing same location is tracked by calculating matching measure. which is defined as the mean of absolute difference between bounding boxes in the current frame and previous frames. Finally. text regions are enhanced using temporal redundancy of bounding boxes to produce final results. Experimental results for various videos show the validity of the proposed method.

Effective Road Area Extraction in Satellite Images Using Texture-Based BP Neural Network (텍스쳐 기반 BP 신경망을 이용한 위성영상의 도로영역 추출)

  • Xu, Zheng;Kim, Bo-Ram;Oh, Jun-Taek;Kim, Wook-Hyun
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.10 no.3
    • /
    • pp.164-169
    • /
    • 2009
  • This paper proposes a road detection method using BP(Back-Propagation) neural network based on texture information of the each candidate road region segmented for satellite images. To segment the candidate road regions, the histogram-based binarization method proposed by N.Otsu is firstly performed and the neighboring regions surrounding road regions are then removed. And after extracting the principal color using the histogram of the segmented foreground, the candidate road regions are classified into the regions within ${\pm}25$ of the principal color. Finally, the road regions are segmented using BP neural network based on texture information of the candidate regions. The texture information in this paper is calculated using co-occurrence matrix and is used as an input data of the BP neural network. The proposed method is based on the fact that the road has the constant intensity and shape. The experiment demonstrated the validity of the proposed method and showed 90% detection accuracy for the various images.

  • PDF

Validation of the Disaster Adaptation and Resilience Scale for Vulnerable Communities in Vietnam's Coastal Regions

  • Thanh Gia Nguyen;Binh Thang Tran;Minh Tu Nguyen;Dinh Duong Le
    • Journal of Preventive Medicine and Public Health
    • /
    • v.57 no.3
    • /
    • pp.279-287
    • /
    • 2024
  • Objectives: This study validated the Vietnamese version of the Disaster Adaptation and Resilience Scale (DARS) for use in vulnerable communities in Vietnam. Methods: This was a cross-sectional study involving 595 adults from 2 identified communities. The original DARS assessment tool was translated, and the validity and reliability of the Vietnamese version of DARS (V-DARS) were assessed. The internal consistency of the overall scale and its subscales was evaluated using Cronbach's alpha and McDonald's omega reliability coefficients. Confirmatory factor analysis (CFA) was employed to evaluate its construct validity, building upon the factor structure identified in exploratory factor analysis (EFA). Construct validity was assessed based on convergent and discriminant validity. Results: Following the established criteria for EFA, 8 items were removed, resulting in a refined V-DARS structure comprising 35 items distributed across 5 distinct factors. Both alpha and omega reliability coefficients indicated strong internal consistency for the overall scale (α=0.963, ω=0.963) and for each of the 5 sub-scales (all>0.80). The CFA model also retained the 5-factor structure with 35 items. The model fit indices showed acceptable values (RMSEA: 0.072; CFI: 0.912; TLI: 0.904; chi-square test: <0.01). Additionally, the convergent and discriminant validity of the V-DARS were deemed appropriate and satisfactory for explaining the measurement structure. Conclusions: Our findings suggest that the V-DARS is a valid and reliable scale for use within vulnerable communities in Vietnam to assess adaptive responses to natural disasters. It may also be considered for use in other populations.