• Title/Summary/Keyword: different regions

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Reduction of Gamma Distortion in Oblique Viewing Directions in Polymer-stabilized Vertical Alignment Liquid Crystal Mode

  • Kim, Hyo Joong;Lim, Young Jin;Murali, G.;Kim, Min Su;Kim, Gi Heon;Kim, Yong Hae;Lee, Gi-Dong;Lee, Seung Hee
    • Current Optics and Photonics
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    • v.1 no.2
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    • pp.157-162
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    • 2017
  • In large liquid crystal displays, the image quality in an oblique viewing direction is a crucial issue. From this perspective, 8-domain polymer-stabilized vertical alignment (PS-VA) mode has been developed to suppress the color shift in oblique viewing directions, compared to that in 4-domain PS-VA mode. To realize the 8-domain PS-VA, the four domains in a pixel are each divided into two regions, such that applying different electric potentials result in different tilt angles in these two regions, while keeping four azimuthal directions in each domain. However, applying different voltages in a pixel causes drawbacks, such as requiring additional processes to construct a capacitor and a transistor, which will further reduce the aperture ratio. Here we propose a different approach to form the 8-domain, by controlling surface polar anchoring energy and the width of patterned electrodes in two regions of a pixel. As a result, the gamma-distortion index (GDI), measured at an azimuthal angle of $0^{\circ}$, is reduced by about 23% and 8%, compared to that of a conventional 4-domain at polar angles of $30^{\circ}$ and $60^{\circ}$ respectively.

Evaluation of median mandibular flexure values in dentulous and edentulous subjects by using an intraoral digital scanner

  • Gulsoy, Merve;Tuna, Suleyman Hakan;Pekkan, Gurel
    • The Journal of Advanced Prosthodontics
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    • v.14 no.1
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    • pp.32-44
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    • 2022
  • PURPOSE. Mandibular flexure is a crucial phenomenon that may affect the success of rigid bilateral mandibular prosthetic treatment. The aim of this study was to determine the amount of median mandibular flexure (MMF) that occurs during mouth opening from anterior to posterior mandible in seven different regions, in different age and gender groups of both dentulous and edentulous subjects, using an intraoral digital scanner. MATERIALS AND METHODS. In this study, the mandibular arch of 56 dentulous and 35 edentulous individuals were scanned with an intraoral scanner at both the minimum mouth opening (MnMO) and the maximum mouth opening (MxMO). MMF values were calculated by subtracting the distance value at the MxMO from the distance between the reference points at the MnMO at seven different mandibular regions of dentulous and edentulous subjects. In addition, the left and right side MMF values were measured. All data were analyzed statistically (α = .05). RESULTS. MMF value increased linearly from anterior to posterior mandible in both dentulous and edentulous individuals. The differences in MMF values were not statistically significant according to side (left/right), age, or gender (P > .05). No significant differences were found between the mean MMF values of the same region in both dentulous and edentulous individuals (P > .05). CONCLUSION. MMF was seen in different regions of the mandibles of both edentulous and dentulous individuals measured at the MxMO. Mandibular flexure should be considered for the success and prognosis of the long-span and rigid prostheses.

A Probabilistic Approach to Forecasting and Evaluating the Risk of Fishing Vessel Accidents in Korea

  • Kim, Dong-Jin
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.3
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    • pp.302-310
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    • 2018
  • Despite the accident rate for fishing vessels accounts for 70% of all maritime accidents, few studies on such accidents have been done and most of the them mainly focus on causes and mitigation policies to reduce that accident rate. Thus, this risk analysis on sea accidents is the first to be performed for the successful and efficient implementation of accident reducing measures. In risk analysis, risk is calculated based on the combination of frequency and the consequence of an accident, and is usually expressed as a single number. However, there exists uncertainty in the risk calculation process if one uses a limited number of data for analysis. Therefore, in the study we propose a probabilistic simulation method to forecast risk not as a single number, but in a range of possible risk values. For the capability of the proposed method, using the criteria with the ALARP region, we show the possible risk values spanning across the different risk regions, whereas the single risk value calculated from the existing method lies in one of the risk regions. Therefore, a decision maker could employ appropriate risk mitigation options to handle the risks lying in different regions. For this study, we used fishing vessel accident data from 1988 to 2016.

Blue excesses in different evolutionary stages of massive star-forming regions

  • Jin, Mihwa;Lee, Jeong-Eun;Kim, Kee-Tae
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.53.3-53.3
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    • 2015
  • We analyzed both HCN J=1-0 and HNC J=1-0 line profiles to study the inflow motions in different evolutionary stages of massive star formation; infrared dark clouds (IRDCs), high-mass protostellar object (HMPOs), and ultra-compact HII regions (UCHIIs). The infall asymmetry in HCN spectra seems to be prevalent throughout all the three evolutionary phases, with IRDCs showing the largest excess in blue profile. In the case of HNC spectra, the prevalence of blue sources does not appear, excepting for IRDCs. We suggest that this line is not appropriate to trace infall motion in evolved stages of massive star formation because of an astrochemical effect. This result spotlights the importance of considering chemistry in dynamical study in star-forming regions. The fact that the IRDCs show the highest blue excess in both infall tracers indicates that the most active infall occurs in the early phase of star formation, i.e., the IRDC phase rather than in the later phases. However, the UCHIIs is likely still accreting matters. We also found that the absorption dips of the HNC spectra in all blue sources are red--shifted relative to their central velocities. These red-shifted absorption dips may indicate the observational signature of overall collapse although observations with better resolutions are needed to examine this feature more in detail.

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The Color Cross-Correlogram for the Robust Image Retrieval in the Size Change of Regions (영역의 크기 변화에 강인한 영상 검색을 위한 칼라 크로스-코렐로그램)

  • An, Myoung-Seok;Cho, Seok-Je
    • The KIPS Transactions:PartB
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    • v.9B no.6
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    • pp.753-758
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    • 2002
  • This paper proposes the color Cross-correlogram and its extraction method for efficient image retrieval. Color cross-correlogram represents the probability that different colors are existed at any two pixels whose distance is fixed in an image. Color cross-correlogram doesn't have the information about the region size that has a color, so color cross-correlogram can have good performance in retrieving images that have different size color regions. The experiments say that we can get the good retrieval results in the images that have various size color regions, and get the better retrieval results when using color cross-correlogram than those of retrieval using color correlogram.

HPV Infection and Cervical Abnormalities in HIV Positive Women in Different Regions of Brazil, a Middle-Income Country

  • Freitas, Beatriz C;Suehiro, Tamy T;Consolaro, Marcia EL;Silva, Vania RS
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.18
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    • pp.8085-8091
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    • 2016
  • Human papillomavirus is a virus that is distributed worldwide, and persistent infection with high-risk genotypes (HR-HPV) is considered the most important factor for the development of squamous cell cervical carcinoma (SCC). However, by itself, it is not sufficient, and other factors may contribute to the onset and progression of lesions. For example, infection with other sexually transmitted diseases such as human immunodeficiency virus (HIV) may be a factor. Previous studies have shown the relationship between HPV infection and SCC development among HIV-infected women in many regions of the world, with great emphasis on low- and middle-income countries (LMICs). Brazil is considered a LMIC and has great disparities across different regions. The purpose of this review was to highlight the current knowledge about HPV infection and cervical abnormalities in HIV+ women in Brazil because this country is an ideal setting to evaluate HIV impact on SCC development and serves as model of LMICs and low-resource settings.

Research Progress on Leptotrombidium deliense

  • Lv, Yan;Guo, Xian-Guo;Jin, Dao-Chao
    • Parasites, Hosts and Diseases
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    • v.56 no.4
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    • pp.313-324
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    • 2018
  • This article reviews Leptotrombidium deliense, including its discovery and nomenclature, morphological features and identification, life cycle, ecology, relationship with diseases, chromosomes and artificial cultivation. The first record of L. deliense was early in 1922 by Walch. Under the genus Leptotrombidium, there are many sibling species similar to L. deliense, which makes it difficult to differentiate L. deliense from another sibling chigger mites, for example, L. rubellum. The life cycle of the mite (L. deliense) includes 7 stages: egg, deutovum (or prelarva), larva, nymphochrysalis, nymph, imagochrysalis and adult. The mite has a wide geographical distribution with low host specificity, and it often appears in different regions and habitats and on many species of hosts. As a vector species of chigger mite, L. deliense is of great importance in transmitting scrub typhus (tsutsugamushi disease) in many parts of the world, especially in tropical regions of Southeast Asia. The seasonal fluctuation of the mite population varies in different geographical regions. The mite has been successfully cultured in the laboratory, facilitating research on its chromosomes, biochemistry and molecular biology.

Image Deblocking Scheme for JPEG Compressed Images Using an Adaptive-Weighted Bilateral Filter

  • Wang, Liping;Wang, Chengyou;Huang, Wei;Zhou, Xiao
    • Journal of Information Processing Systems
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    • v.12 no.4
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    • pp.631-643
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    • 2016
  • Due to the block-based discrete cosine transform (BDCT), JPEG compressed images usually exhibit blocking artifacts. When the bit rates are very low, blocking artifacts will seriously affect the image's visual quality. A bilateral filter has the features for edge-preserving when it smooths images, so we propose an adaptive-weighted bilateral filter based on the features. In this paper, an image-deblocking scheme using this kind of adaptive-weighted bilateral filter is proposed to remove and reduce blocking artifacts. Two parameters of the proposed adaptive-weighted bilateral filter are adaptive-weighted so that it can avoid over-blurring unsmooth regions while eliminating blocking artifacts in smooth regions. This is achieved in two aspects: by using local entropy to control the level of filtering of each single pixel point within the image, and by using an improved blind image quality assessment (BIQA) to control the strength of filtering different images whose blocking artifacts are different. It is proved by our experimental results that our proposed image-deblocking scheme provides good performance on eliminating blocking artifacts and can avoid the over-blurring of unsmooth regions.

Vicarious Calibration-based Robust Spectrum Measurement for Spectral Libraries Using a Hyperspectral Imaging System

  • Chi, Junhwa
    • Korean Journal of Remote Sensing
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    • v.34 no.4
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    • pp.649-659
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    • 2018
  • The aim of this study is to develop a protocol for obtaining spectral signals that are robust to varying lighting conditions, which are often found in the Polar regions, for creating a spectral library specific to those regions. Because hyperspectral image (HSI)-derived spectra are collected on the same scale as images, they can be directly associated with image data. However, it is challenging to find precise and robust spectra that can be used for a spectral library from images taken under different lighting conditions. Hence, this study proposes a new radiometric calibration protocol that incorporates radiometric targets with a traditional vicarious calibration approach to solve issues in image-based spectrum measurements. HSIs obtained by the proposed method under different illumination levels are visually uniform and do not include any artifacts such as stripes or random noise. The extracted spectra capture spectral characteristics such as reflectance curve shapes and absorption features better than those that have not been calibrated. The results are also validated quantitatively. The calibrated spectra are shown to be very robust to varying lighting conditions and hence are suitable for a spectral library specific to the Polar regions.

Analysis of the Effects of Population, Household, and Housing Characteristics on the Status of Empty Houses Using Population Housing Census Data (인구주택 총조사 자료를 이용한 인구, 가구, 주택 특성과 빈집 현황 분석)

  • Lee, Jimin;Choi, Won
    • Journal of The Korean Society of Agricultural Engineers
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    • v.62 no.5
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    • pp.1-13
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    • 2020
  • The empty houses' problem is important in the local revitalization and local sustainability, and these phenomenon caused by various factors of the region. The population and housing census data are the most effective data available to study this phenomenon by small regions. In this study, logistic regression and multiple regression analysis were performed to understand the effects of population, household, and housing characteristics on empty houses using population and housing census data. Also, the scale and direction of the effect of each characteristic in large cities, small cities, and rural areas were compared. As results, there was a slight difference between cities and province regions in the district and housing characteristic variables. In the comparison of Eup-Myeon-Dong, the affected variables were different in the Dong and Myeon areas. The significance of this study is to examine the effect of the characteristics of population and housing on the vacant houses and to confirm that the factors affecting different regions.