통계적 영상 품질 측정

배경율(Kyoung Yul Bae) 한국지능정보시스템학회 2007 지능정보연구 Vol.13 No.4

The image quality measure is an important issue in the image processing. Several methods which measure the image quality have been proposed and these are based on the mathematical point of view. However, there is difference between the mathematicalmeasure and the measure based on the human visual system and a new measure has to be proposed because the final target of the image is a human visual system In this paper, a statistical image quality measure which is considered the human visual feature was suggested. The human visual system is using the global quality of the image and the local quality of the image and the local quality is more important to human visual system. In this paper, the image divided into several segments and the image qualities were calculated respectively. After then, the statistical method using scoring was applied to the image qualities. The result of the image quality measure was similar to the result of measure based on the human visual system.

감각의 복합성과 모더니즘 시의 '회화성' 연구 : 1930년대 김기림·김광균·정지용 시를 중심으로

윤의섭 한중인문학회 2008 한중인문학연구 Vol.25 No.-

본고는 1930년대 모더니즘 시에 나타난 시각적 감각작응의 복합성과 복합감각적 지각 작용에 의해 형성된 이미지의 성격, 그리고 1930년대 모더니즘 시가 강조했던 '회화성의 감각적 의미를 살펴보았다. 감각 작용의 일반적인 특성상 감각 작용은 복합감각적으로 이루어지는데, 시의 회화성과 시각적 감각을 강조했던 1930년대 모더니즘 시의 감각 역시 시각적 감각만 작용한 것이 아니라 시각을 중심으로 여러 감각 작용이 이루어졌다. 즉, 모더니즘 시의 시각중심주의는 대상의 ‘회화성'을 극대화하여 그 시각적 이미지를 형성하는 데에 주력하고 있지만, 실제에 있어서는 시각적 감각 역시 복합감각적 이미지를 보여주고 있는 것이다. 한편 1930년대 모더니즘 시가 강조하는 이미지가 시각적 감각과 깊은 관계를 맺고 있는 것은 사실이나 그 이미지와 이미지가 내포하고 있는 의미를 의도한 바대로 드러내기 위해서는 대상에 대한 복합감각적 지각이 함께 이루어지고 있었다. 이와 함께 회화성이 갖는 감각적 의미는 다음과 같다. 당시 모더니즘 시의 '회화성'에 나타난 감각은 복합감각적 지각에 의한 동시적 지각의 양상을 보이며 입체적이며 다원적인 공간성을 형성하고 있다. 그리고 1930년대 모더니즘 시가 중요시한 이미지 획득이라는 의도와 함께 시각적 감각이 갖는 종합적 인식의 특성이 가세해 시각적 감각이 두드러지게 나타나고 있다. 그럼에도 복합감각적 회화성이 시에 드러나고 있는 것은 1930년대의 근대적 풍경을 근대적인 시각으로 더듬어보고자 하는 당시 모더니즘 시인들의 감각적 인식 태도가 반영되어 있기 때문이다. This paper covers complexity of visual sensibility in Modernism poetry in 1930s; characteristics of the images formed by perception of complex senses: and significance of sensibility in picturesque quality emphasized by Modernism poetry in 1930s. Due to its generalized nature, effect of sensibility is achieved by complex senses; sensibility in Modernism poetry in 1930s, which emphasized picturesque quality and visual sensibility, was also achieved by various effects of sensibility focusing on visual sense, not solely by visual sensibility, In other words, visual-oriented tendency in Modernism poetry maximized picturesque quality' in an object to form visual image; however it actually shows image of complex senses. Although it is true that images emphasized in Modernism poetry in 1930s have close relationship with visual sensibility, complex senses were at work in order to convey meaning of an image as intended, In addition, significance of 'picturesque quality' in terms of sensibility is as follows: sensibility shown in 'picturesque quality in Modernism poetry at that time created a quality of space that is three-dimensional and plural, showing synchronized perception of complex senses. Also with intention to achieve image which Modernism poetry in 1930s emphasized, visual sensibility stands out with help of nature of complex perception, Picturesque quality of complex senses in poetry, notwithstanding, is because of clear reflection of perception of senses among Modernism poets of the time who attempted to view modern landscape in 1930s through modern viewpoint.

Saliency Score-Based Visualization for Data Quality Evaluation

Yong Ki Kim,Keon Myung Lee 한국지능시스템학회 2015 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.15 No.4

Data analysts explore collections of data to search for valuable information using various techniques and tricks. Garbage in, garbage out is a well-recognized idiom that emphasizes the importance of the quality of data in data analysis. It is therefore crucial to validate the data quality in the early stage of data analysis, and an effective method of evaluating the quality of data is hence required. In this paper, a method to visually characterize the quality of data using the notion of a saliency score is introduced. The saliency score is a measure comprising five indexes that captures certain aspects of data quality. Some experiment results are presented to show the applicability of proposed method.

Evaluation of Visual Quality afte Femtosecond Laser LASIK

Hui-June Kim,Koon-Ja Lee 대한시과학회 2016 대한시과학회지 Vol.18 No.3

목 적: 펨토초레이저(Fentosecond laser)를 이용한 라식 수술 후 이중경로방식(double-pass technique) 으로 시력의 질을 평가하였다. 방 법: 펨토초레이저를 이용한 라식 수술을 받은 중등도 및 고도 근시안(평균 등가구면굴절력: -3.93 ± 1.48 D) 43명(85 안, 평균연령: 26.35 ± 6.86세)을 대상으로 하였다. 시력의 질은 수술 전과 수술 1주일 및 1개월 후에 Optical Quality Analysis System(OQAS) 장비를 이용하였고, modulation transfer function(MTF), Strehl ratio, objective scattering index(OSI) 및 객관적 시력(OQAS values, OVs)을 측 정하여 평가하였다. 결 과: 수술 1개월 후 MTF cutoff 값, Strehl ratio, OSI, OV100%, OV20% 및 OV9% 는 각각 41.67 ± 9.99 cycles/degree, 0.24 ± 0.06, 0.45 ± 0.19, 1.41 ± 0.28, 1.06 ± 0.26, 0.66 ± 0.18로 이 값들은 수술 전과 유의한 차이가 없었다(MTF p=0.23, Strehl ratio p=0.19, OSI p=0.19). 또한 객관적 시력 OV100%, OV20%, OV9% 도 모두 수술 전과 비교하여 유의한 차이를 보이지 않았다(p=0.95, p=0.10, p=0.10). 결 론: 펨토초레이저 라식 1개월 후 시력의 질은 수술 전 안경렌즈로 교정한 값과 차이를 보이지 않아 좋 은 시력의 질을 제공하는 것으로 생각된다. Purpose: To investigate visual quality with double-pass technique after LASIK using a Femtosecond Laser. Methods: We examined 43 patients of moderate and high myopia (mean manifest spherical equivalent: -3.93 ± 1.48 D, 85 eyes, mean age: 26.35 ± 6.86 years) undergoing Feomtosecond Laser LASIK (FS-LASIK). Visual quality was assessed with a Optical Quality Analysis System (OQAS) before and 1 week and 1 month after surgery. The modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI) and OQAS values (OVs) were measured and these variables were compared. Results: The mean MTF cutoff frequency, Strehl ratio, OSI, OV100%, OV20%, OV9% were 41.67 ± 9.99 cycles/degree, 0.24 ± 0.06, 0.45 ± 0.19, 1.41 ± 0.28, 1.06 ± 0.26, and 0.66 ± 0.18, respectively, 1 months after FS-LASIK and no significant differences compared to the baseline results (MTF p=0.23 Strehl ratio p=0.19, OSI p=0.19). There were no differences in OVs at contrasts of 100% (p=0.95), 20% (p=0.10), and 9% (p=0.10) 1 months after FS-LASIK compared to the baseline results. Conclusions: The visual quality 1 month after FS-LASIK was not significantly different compared to the eyes corrected with spectacle lenses before the surgery, suggesting that FS-LASIK provide a good visual quality.

펨토초레이저 라식 수술 후 시력의 질 평가

김희준,이군자 대한시과학회 2016 대한시과학회지 Vol.18 No.3

목 적: 펨토초레이저(Fentosecond laser)를 이용한 라식 수술 후 이중경로방식(double-pass technique)으로 시력의 질을 평가하였다. 방 법: 펨토초레이저를 이용한 라식 수술을 받은 중등도 및 고도 근시안(평균 등가구면굴절력: -3.93 ± 1.48 D) 43명(85 안, 평균연령: 26.35 ± 6.86세)을 대상으로 하였다. 시력의 질은 수술 전과 수술 1주일 및 1개월 후에 Optical Quality Analysis System(OQAS) 장비를 이용하였고, modulation transfer function(MTF), Strehl ratio, objective scattering index(OSI) 및 객관적 시력(OQAS values, OVs)을 측정하여 평가하였다. 결 과: 수술 1개월 후 MTF cutoff 값, Strehl ratio, OSI, OV100%, OV20% 및 OV9% 는 각각 41.67 ± 9.99 cycles/degree, 0.24 ± 0.06, 0.45 ± 0.19, 1.41 ± 0.28, 1.06 ± 0.26, 0.66 ± 0.18로 이 값들은 수술 전과 유의한 차이가 없었다(MTF p=0.23, Strehl ratio p=0.19, OSI p=0.19). 또한 객관적 시력 OV100%, OV20%, OV9% 도 모두 수술 전과 비교하여 유의한 차이를 보이지 않았다(p=0.95, p=0.10, p=0.10). 결 론: 펨토초레이저 라식 1개월 후 시력의 질은 수술 전 안경렌즈로 교정한 값과 차이를 보이지 않아 좋은 시력의 질을 제공하는 것으로 생각된다. Purpose: To investigate visual quality with double-pass technique after LASIK using a Femtosecond Laser. Methods: We examined 43 patients of moderate and high myopia (mean manifest spherical equivalent: -3.93 ± 1.48 D, 85 eyes, mean age: 26.35 ± 6.86 years) undergoing Feomtosecond Laser LASIK (FS-LASIK). Visual quality was assessed with a Optical Quality Analysis System (OQAS) before and 1 week and 1 month after surgery. The modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI) and OQAS values (OVs) were measured and these variables were compared. Results: The mean MTF cutoff frequency, Strehl ratio, OSI, OV100%, OV20%, OV9% were 41.67 ± 9.99 cycles/degree, 0.24 ± 0.06, 0.45 ± 0.19, 1.41 ± 0.28, 1.06 ± 0.26, and 0.66 ± 0.18, respectively, 1 months after FS-LASIK and no significant differences compared to the baseline results (MTF p=0.23 Strehl ratio p=0.19, OSI p=0.19). There were no differences in OVs at contrasts of 100% (p=0.95), 20% (p=0.10), and 9% (p=0.10) 1 months after FS-LASIK compared to the baseline results. Conclusions: The visual quality 1 month after FS-LASIK was not significantly different compared to the eyes corrected with spectacle lenses before the surgery, suggesting that FS-LASIK provide a good visual quality.

Objective Assessment of Visual Quality and Ocular Scattering Based on Double-pass Retinal Images in Refractive-surgery Patients and Emmetropes

김정미 한국광학회 2019 Current Optics and Photonics Vol.3 No.6

This study was performed to evaluate objective visual quality and ocular scattering in myopic refractivesurgery patients, compared to emmetropes. Optical vision-quality parameters (modulation transfer function (MTF) cutoff and Strehl ratio) and objective scattering index (OSI) were measured using an optical quality analysis system (OQAS II) based on the double-pass technique. In all subjects, the higher the MTF cutoff and Strehl ratio, the lower the OSI and ocular higher-order aberrations (HOAs). The MTF cutoff and Strehl ratio for the laser-assisted subepithelial keratectomy (LASEK) group were lower than those for the emmetropia group, while the OSI, ocular HOAs, and spherical aberration (SA) for the LASEK group were higher than those for emmetropia group. Ocular scattering would be one of the important factors in regard to visual quality. Therefore, the quality of the retinal image in the LASEK patients has been shown to reduce the quality of vision more than in the emmetropes.

Analysis of the Visual Quality of Riverfront Skyline Through the Feature of Height and Spatial Arrangement of Tall Building

아유 완디라 뿌스삐따사리,권종욱 대한건축학회 2019 Architectural research Vol.21 No.4

In modern times, numerous cities are competing to create the unique skyline adjacent to the water. Tall buildings locatedacross the river have a great contribution to the skyline of a riverfront city and can be a precious asset for the city. Moreover, inseveral cities, tall buildings and their impact on the urban skyline are a matter that should be considered and regulated in urbandesign. Therefore, as a prominent element in a larger visual setting of the city, tall buildings should improve the visual quality ofthe skyline rather than diminish that quality. This research attempts to provide an objective method to analyze the visual quality ofthe skyline made by a group of tall buildings through their feature of heights and spatial arrangement from riverfront views. Theanalysis is determined by the design variables of building heights variation, heights transition, density, and spacing of a group oftall buildings. A comparative case study of tall buildings in Yeouido and Lujiazui was conducted to prove the effectiveness of theanalysis. The proposed method can be used in a simple way in the quantitative approach to quantify the visual quality of the skyline. In conclusion, Yeuido’s skyline is not quite interesting from the riverfront view in terms of height variation and continuity of theskyline view because they are dispersed. Conversely, Lujiazui’s skyline from the riverfront vantage points has a good quality in allaspects of the feature of height and spatial arrangements of tall buildings cluster. These factors can be used for the urban designer onhow proposed tall buildings within the cluster should appropriately respond to adding image on the skyline.

지리산(智異山) 국립공원(國立公園) 도로(道路)비탈면의 식생(植生)과 경관분석(景觀分析)에 관한 연구(硏究)(II) -경관분석(景觀分析)-

서병수,김세천,박종민,이창헌,이규완,Seo, Byung-Soo,Kim, Sei-Cheon,Park, Chong-Min,Lee, Chang-Heon,Lee, Kyu-Wan 한국산림과학회 1991 한국산림과학회지 Vol.80 No.3

지리산국립공원(智異山國立公園)의 도로(道路) 비탈면을 대상(對象)으로 물리적(物理的) 환경(環境)이 지닌 시각적(視覺的) 질(質)을 계량적(計量的) 접근방법(接近方法)으로 분석하여 합리적인 계획(計劃), 설계(設計) 및 보전관리(保全管理)에 필요한 기초자료(基礎資料)를 제시하는 것을 목적(目的)으로, 도로(道路) 비탈면 구성요소의 물리량을 Mesh 분석법(分析法)에 의하여 측정(測定)하였다 또한 심리량 분석(分析)을 위해 S.D Scale을 측정하고 인지분석 Algorithm을 통하여 물리적 환경(環境)의 공간(空間) 이미지 구조(構造)를 밝혔으며, 시각적(視覺的) 선호도(選好度)를 측정하여 결정인자(決定因子) 추출(抽出)과 각(各) 인자(因子) 상호간(相互間) 중요성(重要性)을 규명하였다. Mesh 분석(分析)에 의한 시각량조사(視覺量調査) 결과(結果), 각(各) 지점 공(共)히 이지(裡地)와 암석 비탈면, seed spray 등에 의한 지피식생지(池被植生地), 인공식생지등(人工植生地等)이 상대적으로 높은 측정치를 보였다. 국립공원(國立公園) 도로비탈면의 공간 이미지를 함축하는 변인(變因)은 종합평가(綜合評價) 차원(次元), 공간적(空間的) 차원(次元), 호감성(好感性) 차원(次元), 물리적(物理的) 차원(次元), 개방적(開放的) 차원(次元) 및 품격(品格) 차원(次元) 등 6개 인자군(因子群)으로 분석되었으며, 공간적 차원, 물리적 차원 및 개방성 차원(次元)의 인자가 공간 이미지를 대표하는 인자군으로 나타났다. 비탈면 경관(景觀)에 대한 시각적(視覺的) 선호도(選好度)를 결정(決定)짓는 주요(主要) 설명변수는 비탈면내 구조물의 유지관리정도와 비탈면내의 주변 경관과의 어울림과 조화(調和)로움, 비탈면내 인공식생(人工植生)과 구조물(構造物) 등(等)으로 시각적(視覺的) 선호도(選好度) 결정(決定)의 주요(主要) 설명변수로 나타났다. The purpose of this study is to suggest objective basic data for the design and management of the national park roadside slopes through the quantitative analysis of the visual quality included in the physical environment of the Chi-ri national park, for this, visual volumes of physical elements have been evaluated by using the mesh analysis, spatial images structure of physical elements have been analyzed by factor analysis algorithm, and degree of visual quality have been measured mainly by questionnaires. Result of this thesis can be summarized as fallows. Visual volumes of the naked, rock, ground cover of seed spray, and artificial planting are found to be the main factor determining the visual quality. Factors covering the spatial image of the national park roadside slopes landscape have been found to be the overall synthetic evaluation, spatial, appeal, physical, openness and dignity factors such as the overall the spatial, physical and openness yield high factor scores. As for the factors determining the degree of visual quality of the roadside slopes, variables such as the summit, the constructions management, harmony of landscape, visual stability of roadside slopes, suitable artificial planting and suitable constructions.

후낭혼탁 환자에서 야그레이저 후낭절개술 전과 후의 시력의 광학적 평가

박창원,안영주,김효진 한국안광학회 2020 한국안광학회지 Vol.25 No.2

Purpose: To evaluate the change in visual acuity related to differences in visual function before and after Nd: YAG laser surgery in patients with posterior capsular opacification. Methods: Eyes of 255 patients (one eye from each patient) aged 50-79 years who were diagnosed with posterior capsular opacification and treated with Nd: YAG laser were used in this study. Optical evaluation of visual acuity using the OQAS (optical quality analysis system) was performed before and after one week and one month following Nd: YAG laser surgery. The optical evaluation parameters included the ocular scatter index (OSI), modulation transfer function (MTF), image concentration ratio (strehl ratio), and simulated visual acuity at 100% contrast (simulated VA C=100%). Simulated visual acuities at 20% (simulated VA C (contrast) = 20%) and 9% (simulated VA C=9%) contrasts were analyzed. Results: The OSI of patients with posterior capsular opacification was 3.28±1.95 preoperatively; at 1 month postoperatively, it significantly decreased to 1.77±1.04. MTF (C/deg) increased from 18.17±4.85 to 30.33±7.14, and the Strehl ratio improved significantly from 0.08±0.04 to 0.15±0.11 (p < 0.001). The simulated visual acuity under varied contrast conditions improved from 0.49±0.28 before surgery to 0.91±0.42 at 1 month under daytime (C=100%) and nighttime (C=20%) conditions. Simulated visual acuities improved from 0.34±0.23 before surgery to 0.75±0.35 at 1 month after surgery. For darkroom conditions (C=9%), the simulated visual acuity significantly improved from 0.21±0.12 before surgery to 0.47±0.27 at 1 month after surgery. Conclusion: Posterior capsulotomy using Nd: YAG laser showed improvement in visual and optical qualities. It facilitated the objective assessment of improvements in visual acuity and a better understanding of visual function in patients. 목적: 후낭혼탁 환자를 대상으로 Nd:YAG 레이저를 이용한 술 전과 후에 시력의 변화를 광학적으로 평가하여 질 적 변화를 알아보았다. 방법: 후낭혼탁으로 진단받고 Nd:YAG 레이저를 이용하여 치료받은 50-79세의 255명 255안 을 대상으로 하였다. 오카스 광학측정 장비를 이용하여 레이저 술 전과 레이저 술 후 1달 째에 시력의 광학적 평가 를 시행하였다. 광학적 평가 항목으로는 객관적 산란지수(objective scatter index; OSI), 변조전달함수(modulation transfer function; MTF), 상의 집속률(strehl ratio), 대비도 100%의 가상시력(simulated VA C=100%), 대비도 20%의 가상시력(simulated VA C=20%), 그리고 대비도 9%의 가상시력(simulated VA C=9%)을 분석하였다. 결과: 후낭혼 탁 환자들의 객관적 산란지수는 술 전 3.28±1.95(OSI value)으로 나타났는데 술 후 1달 째에는 1.77±1.04(OSI value) 로 통계학적으로 유의하게 낮아졌고 변조전달함수는 18.17±4.85에서 30.33±7.14로, 상의 집속률은 0.08±0.04에서 0.15±0.11로 유의하게 개선되었다(p<0.001). 대비도 조건에 따른 가상시력은 주간(C=100%) 조건에서 술 전 0.49±0.28(simulated VA)에서 1달 째에 0.91±0.42(simulated VA)로 향상되었고, 야간조건(C=20%)에서는 술 전 0.34±0.23(simulated VA)에서 술 후 1달 째에 0.75±0.35(simulated VA)으로 개선되었다. 반암실조건(C=9%)에서도 술 전 0.21±0.12(simulated VA)에서 술 후 1달 째에 0.47±0.27(simulated VA)으로 광학적 질이 유의하게 개선되는 것으 로 나타났다. 결론: 후낭혼탁 Nd:YAG 레이저를 이용한 후낭절개술은 시력의 개선과 함께 광학적 질의 향상을 가 져오는 것으로 관찰되었고, 시력의 개선 정도를 객관적으로 나타내어 환자의 시기능 상태를 파악하는데 도움이 될 것으로 생각된다.

염해지에서 크리핑벤트그래스 10개 품종의 생육 비교

김준범,양근모,최준수 한국잔디학회 2008 Weed & Turfgrass Science Vol.22 No.2

This study was carried out to examine the growth performance of 10 cultivars of creeping bentgrass under salt injury in Seo-san reclaimed area. Turfgrass performance studies included 10 creeping bentgrass cultivars (T-1, L-93, Penn A1, Pennlinks Ⅱ, Seaside Ⅱ, Declaration, Penn A4, Crenshaw, Dominant, and Penncross). Ten creeping bentgrass cultivars were grown on a USGA recommended research green. Plots were seeded on May 31, 2006 at the rate of 7 g・m-1. Electric conductivities of irrigation water (ECw) and soil (ECe) were ranged from 0.28 to 3.3 d S・m-¹ and from 0.25 to 3.5 d S・m-¹ respectively. Leaf color, turf quality, coverage rate, and growth rate were checked under the salty condition in reclaimed land for 2 year. Creeping bentgrass cultivars of T-1, Pennlinks, and Crenshaw presented dark green color and Penn A1, Declaration showed lighter green color. Penn A1, Penn A4 and L-93 exhibited the highest overall turfgrass quality. Average visual coverage was 75.3% after eleven weeks after seeding. Dominant, L-93, and Penn A1 resulted in higher visual coverage compared to the other cultivars. There was no difference in density among cultivars at 1 year after establishment. However, Declaration, Penn A1, T-1, and L-93 showed higher density compared to the other cultivars at 2 years after seeding. Creepingbentgrass showed different quality, density and color in salty soil (ECe: 0.25-3.5 d S・ m-¹) and from application of salty irrigation water (ECw: 0.28-3.3 d S・m-¹) conditions. These results will be useful where selecting green cultivars for the golf courses in reclaimed land area. This study was carried out to examine the growth performance of 10 cultivars of creeping bentgrass under salt injury in Seo-san reclaimed area. Turfgrass performance studies included 10 creeping bentgrass cultivars (T-1, L-93, Penn A1, Pennlinks Ⅱ, Seaside Ⅱ, Declaration, Penn A4, Crenshaw, Dominant, and Penncross). Ten creeping bentgrass cultivars were grown on a USGA recommended research green. Plots were seeded on May 31, 2006 at the rate of 7 g・m-1. Electric conductivities of irrigation water (ECw) and soil (ECe) were ranged from 0.28 to 3.3 d S・m-¹ and from 0.25 to 3.5 d S・m-¹ respectively. Leaf color, turf quality, coverage rate, and growth rate were checked under the salty condition in reclaimed land for 2 year. Creeping bentgrass cultivars of T-1, Pennlinks, and Crenshaw presented dark green color and Penn A1, Declaration showed lighter green color. Penn A1, Penn A4 and L-93 exhibited the highest overall turfgrass quality. Average visual coverage was 75.3% after eleven weeks after seeding. Dominant, L-93, and Penn A1 resulted in higher visual coverage compared to the other cultivars. There was no difference in density among cultivars at 1 year after establishment. However, Declaration, Penn A1, T-1, and L-93 showed higher density compared to the other cultivars at 2 years after seeding. Creepingbentgrass showed different quality, density and color in salty soil (ECe: 0.25-3.5 d S・ m-¹) and from application of salty irrigation water (ECw: 0.28-3.3 d S・m-¹) conditions. These results will be useful where selecting green cultivars for the golf courses in reclaimed land area.