• Title/Summary/Keyword: Observer Characteristic Function

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An Adaptive Colorimetry Analysis Method of Image using a CIS Transfer Characteristic and SGL Functions (CIS의 전달특성과 SGL 함수를 이용한 적응적인 영상의 Colorimetry 분석 기법)

  • Lee, Sung-Hak;Lee, Jong-Hyub;Sohng, Kyu-Ik
    • Journal of Korea Multimedia Society
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    • v.13 no.5
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    • pp.641-650
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    • 2010
  • Color image sensors (CIS) output color images through image sensors and image signal processing. Image sensors that convert light to electrical signal are divided into CMOS image sensor and CCD image sensor according to transferring method of signal charge. In general, a CIS has RGB output signals from tri-stimulus XYZ of the scene through image signal processing. This paper presents an adaptive colorimetric analysis method to obtain chromaticity and luminance using CIS under various environments. An image sensor for the use of colorimeter is characterized based on the CIE standard colorimetric observer. We use the method of least squares to derive a colorimetric characterization matrix between camera RGB output signals and CIE XYZ tristimulus values. We first survey the camera characterization in the standard environment then derive a SGL(shutter-gain-level) function which is relationship between luminance and auto exposure (AE) characteristic of CIS, and read the status of an AWB(auto white balance) function. Then we can apply CIS to measure luminance and chromaticity from camera outputs and AE resister values without any preprocessing. Camera RGB outputs, register values, and camera photoelectric characteristic are used to analyze the colorimetric results for real scenes such as chromaticity and luminance. Experimental results show that the proposed method is valid in the measuring performance. The proposed method can apply to various fields like surveillant systems of the display or security systems.

A Study on the Running Type Nipper Pattern Development for Adult men (성인 남성용 런닝형 니퍼패턴 개발)

  • Cho, Pyeong-Hun;Shon, Hoo-Jo;Na, Mi-Hyang
    • Korean Journal of Human Ecology
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    • v.16 no.3
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    • pp.577-585
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    • 2007
  • This research aimed for 20 latter man whose body shape of torso alters remarkably to develop nipper pattern of running type considered characteristic of body shape of 20 latter man to keep rather balanced body shape against middle age when body shape changes extremely. 1. running type nipper pattern design. Pattern of running, lining and nipper were designed by flattening surface shell. A basis line of running pattern is completed by applying reduction ratio after 3 times of modification & complement based on surface shell. Nipper pattern is designed with design line set by a plaster cast based on running pattern line. Lining pattern is designed with lining design line set by a plaster cast based on running type outside material and nipper pattern. 2. Functional evaluation of research and commercial nipper. Functional inspection through dress test was applied 5point evaluation method and the result of functional inspection on the sight of a wearer is that research nipper(running reduction ratio 15%, nipper reduction ratio 18%) averaged more 4.8point but commercial nipper averaged less 1.8point in the aspect of 20 items such as wear sensibility, motional function and external appearance aesthetic. Research running type nipper scored high in order of motional function, looks of side, back, front and whole and wear sensibility. Functional inspection in the point of view of an observer is that research nipper(running reduction ratio 15%, nipper reduction ratio 18%) averaged over 4.8point and commercial nipper averaged under 1.9point in 17 items of external appearance beauty. Research running type nipper marked high in order of looks of back, whole, front and side.

A Study on the Multiplicity of Architectural Skin in Contemporary Architecture (현대건축의 표피에서 나타나는 다질성의 특성 연구)

  • Kim, Do-Woon;Kim, Dong-Jin
    • Korean Institute of Interior Design Journal
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    • v.23 no.6
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    • pp.22-32
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    • 2014
  • Development of digital technology, which is individualizing and differentiating the world, makes time and space facilitate multi-layering in the contemporary society. It gives a large influence on the contemporary architecture that inducing the visual and spatial experience. Also, It generates new images through the skin of architecture, which implies the contingent and fluid characteristics. These phenomenon show that various parameters are working on the architectural skin simultaneously. Such complexity make the structure of open space and diversity that are homogenized and synchronized. Like this, the architectural skin implies 'multiplicity': qualitative difference which is enable to change and create new images. This characteristic generates instant images changing variously and semantics constantly by the function of skin as a filter. Also, the architectural skin integrates or relocates of relationships between the various information and elements appearing in contemporary society in order to escape the customary relationship between internal and external. Furthermore, the inside and outside of the mixture as a collection of sense has been recognized as one image. This image of mixture consists of one unified continuous integration and extend the meaning of a fluid interface not just surface of the building. The skin of the contemporary architecture is very technical, so its meaning and role is expanded as a complex that exchange interaction. This means that the skin itself has functional elements of the integrated multiple skin to assist. Also it can form a multi-layered relationship and act as a wide range of interfaces depending on the perception of the observer. Therefore the multiplicity of the architectural skin indicates the importance as a boundary that generate images of new life through the sensory perception and implicit force. And it shows potential as the intermediary to try to communicate.

Effects of Myofascial Release and Posture Correction Exercise on the Neck Movement and the Quality of Sleep in Patients with Chronic Tension-Type Headaches

  • Cho, Sunghak
    • Journal of International Academy of Physical Therapy Research
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    • v.10 no.4
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    • pp.1897-1902
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    • 2019
  • Background: Tension-type headaches, which make up the highest proportion of headaches, are prone to develop into chronic tension-type headaches (CTTH). The characteristic of CTTH in patients is that the active myofascial trigger point (ATrP) which causes pain in the muscles of the back of the head is increased, compared to the normal headache and moves the head position forward. Objective: The aim of this study was to investigate the effects of myofascial release (MFR) and posture correction in effectively improving neck function and sleep quality in the symptoms of CTTH patients. Design: Observer-blind study Methods: To reduce ATrP, MFR was applied and exercise was also applied to correct posture. The subjects of this study were 48 individuals randomly divided into three groups; The MFR group using the MFR technique; The MFR with exercise group subject to both the MFR technique and forward head position correction exercises (MFREx), and the control group. MFR and MFREx groups were given the relevant interventions twice a week for four consecutive weeks, and went through the number ATrPs, range of motion (ROM) of neck, Neck Disability Index (NDI) and the Pittsburgh Sleep Quality Index (PSQI) before and after the intervention. A physical therapist, who was fully familiar with the measuring methods of the equipment, was the measurer and not aware of the target's condition was blinded to take measurements only before and after intervention. Results: There was a significant improvement in the ATrP, Neck ROM, NDI and PSQI in the group of patients to whom the MFR technique and MFREx were applied. MFREx was more effective in increasing neck mobility. Conclusions: According to this study, the application of MFR is effective in improving neck movement and sleep quality in chronic tension headache patients.

Optimization of exposure parameters and relationship between subjective and technical image quality in cone-beam computed tomography

  • Park, Ha-Na;Min, Chang-Ki;Kim, Kyoung-A;Koh, Kwang-Joon
    • Imaging Science in Dentistry
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    • v.49 no.2
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    • pp.139-151
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    • 2019
  • Purpose: This study was performed to investigate the effect of exposure parameters on image quality obtained using a cone-beam computed tomography (CBCT) scanner and the relationship between physical factors and clinical image quality depending on the diagnostic task. Materials and Methods: CBCT images of a SedentexCT IQ phantom and a real skull phantom were obtained under different combinations of tube voltage and tube current (Alphard 3030 CBCT scanner, 78-90 kVp and 2-8 mA). The images obtained using a SedentexCT IQ phantom were analyzed technically, and the physical factors of image noise, contrast resolution, spatial resolution, and metal artifacts were measured. The images obtained using a real skull phantom were evaluated for each diagnostic task by 6 oral and maxillofacial radiologists, and each setting was classified as acceptable or unacceptable based on those evaluations. A statistical analysis of the relationships of exposure parameters and physical factors with observer scores was conducted. Results: For periapical diagnosis and implant planning, the tube current of the acceptable images was significantly higher than that of the unacceptable images. Image noise, the contrast-to-noise ratio (CNR), the line pair chart on the Z axis, and modulation transfer function (MTF) values showed statistically significant differences between the acceptable and unacceptable image groups. The cut-off values obtained using receiver operating characteristic curves for CNR and MTF 10 were useful for determining acceptability. Conclusion: Tube current had a major influence on clinical image quality. CNR and MTF 10 were useful physical factors that showed significantly associations with clinical image quality.