• 제목/요약/키워드: index of visual function

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기관지천식 환자에서 폐기능검사와 호흡곤란지수의 관련성에 관한 연구 (Assessment of the Relationship between Pulmonary Function Test and Dyspnea Index in Patients with Bronchial Asthma)

  • 김세규;천선희;장준;하종원;홍천수;김성규;이원영
    • Tuberculosis and Respiratory Diseases
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    • 제39권5호
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    • pp.392-399
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    • 1992
  • 연구배경 : 호흡곤란은 호흡기질환 환자의 가장 흔한 주소이나 이를 감지하는 정확한 기전은 아직 잘 알려져 있지 않다. 폐질환에서 호흡곤란의 심한 정도와 치료에 대한 반응을 측정하는 데 있어 객관적인 폐기능을 이용하여 왔으나 호흡곤란은 폐 환기능 뿐 아니라 심장, 폐질환, 심인적 요인 등을 반영한 복합적인 증상이므로 주관적으로 측정하는 호흡곤란지수(dyspnea index)를 사용하여 이러한 증상의 정도를 양적으로 측정하는 것도 유용할 것으로 생각된다. 방법 : 증상이 기관지천식 환자를 대상으로 Visual Analogue Scale(VAS) 및 Borg Scale Dyspnea Index (BSDI)와 Spirometry를 검사전 휴식상태, methacholine 유발검사에서 양성을 나타내었을 때, 기관지확장제 투여후 각각 측정하였다. 결과 : 1) 기저상태와 Methacholine 및 기관지확장제 투여후 시행한 폐기능검사 결과와 VAS 및 BSDI 간 상관관계는 없었다. 2) FEV1, FVC 및 MMFR 변화량과 VAS 및 BSDI 변화량 간에도 상관관계는 없었다. 3) 천식의 증상호소가 경미한 환자군이 증상호소가 심한 환자군 보다 methacholine 및 기관지확장제 투여 후의 VAS 및 BSDI의 변화가 더 컸다. 4) 호흡곤란지수중 VAS이 BSDI 보다 조금 큰 수치 및 변화량을 보였으며 두 지수 간의 상관관계를 볼 수 있었다(R=0.82). 결론 : 기관지천식 환자에서 기저상태 및 Methacholine 유발검사시에 객관적인 폐기능 검사 수치의 유의한 차이가 없음에도 불구하고 주관적인 호흡곤란지수는 변화하는 경향을 보였으며, 이는 경중 천식군에서 더욱 뚜렷하였다. 호흡곤란지수는 환자 간의 비교척도로는 사용될 수 없으나 한 환자에서 경과관찰이나 치료효과를 판정하는데에 spirometry와 함께 중요한 지표가 될 것으로 생각된다.

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Human Visual System-aware Dimming Method Combining Pixel Compensation and Histogram Specification for TFT-LCDs

  • Jin, Jeong-Chan;Kim, Young-Jin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권12호
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    • pp.5998-6016
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    • 2017
  • In thin-film transistor liquid-crystal displays (TFT-LCDs), which are most commonly used in mobile devices, the backlight accounts for about 70% of the power consumption. Therefore, most low-power-related studies focus on realizing power savings through backlight dimming. Image compensation is performed to mitigate the visual distortion caused by the backlight dimming. Therefore, popular techniques include pixel compensation for brightness recovery and contrast enhancement, such as histogram equalization. However, existing pixel compensation techniques often have limitations with respect to blur owing to the pixel saturation phenomenon, or because contrast enhancement cannot adequately satisfy the human visual system (HVS). To overcome these, in this study, we propose a novel dimming technique to achieve both power saving and HVS-awareness by combining the pixel compensation and histogram specifications, which convert the original cumulative density function (CDF) by designing and using the desired CDF of an image. Because the process of obtaining the desired CDF is customized to consider image characteristics, histogram specification is found to achieve better HVS-awareness than histogram equalization. For the experiments, we employ the LIVE image database, and we use the structural similarity (SSIM) index to measure the degree of visual satisfaction. The experimental results show that the proposed technique achieves up to 15.9% increase in the SSIM index compared with existing dimming techniques that use pixel compensation and histogram equalization in the case of the same low-power ratio. Further, the results indicate that it achieves improved HVS-awareness and increased power saving concurrently compared with previous techniques.

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

  • Kim, Jeong-mee
    • Current Optics and Photonics
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    • 제3권6호
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    • pp.597-604
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    • 2019
  • This study was performed to evaluate objective visual quality and ocular scattering in myopic refractive-surgery 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.

The Effect of Hypnotics on Sleep Quality and Cognitive Function in Patients with Brain Tumors

  • Chang, Min Cheol;Chun, Min Ho
    • Journal of Korean Neurosurgical Society
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    • 제63권2호
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    • pp.261-267
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    • 2020
  • Objective : We investigated the effect of hypnotics on sleep quality, cognitive function, and depressive mood in patients with insomnia following brain tumor resection. Methods : From patients who underwent brain tumor resection, we recruited 10 patients with insomnia who received hypnotics for more than 1 week during a 3-week follow-up period (insomnia group). We also recruited 12 control patients with brain tumors but without insomnia (control group). We evaluated sleep quality at baseline and 3 weeks later using the Insomnia Severity Index (ISI), the Pittsburgh Sleep Quality Index (PSQI), the Stanford Sleepiness Scale (SSS), and the Epworth Sleepiness Scale (ESS) and investigated cognitive function and depression using the Computerized Neuropsychological Test and the Beck Depression Inventory (BDI). Results : At baseline, SSS, ISI, PSQI, and BDI scores were significantly higher and visual continuous performance test (VCPT) and auditory continuous performance test (ACPT) scores were significantly lower in the insomnia than in the control group. Three weeks later, the patients who had received hypnotics had significantly higher ISI, PSQI, ESS, VCPT, ACPT, visual span forward and backward, and visual recognition test scores, and significantly lower BDI scores. Conclusion : Quality of sleep in patients with insomnia following brain tumor resection was initially poor but improved significantly after taking hypnotic medication. Further, the hypnotic medications appeared to contribute to the amelioration of cognitive impairments and depressive moods in patients who previously underwent brain tumor resection. We thus recommend the use of hypnotics for patients with brain tumors with insomnia.

근막통증 증후군 환자에게 체외충격파와 근막이완술 병행 치료가 통증, 움직임, 기능에 미치는 영향 (Effects of Extracorporeal Shock Wave Therapy with Myofascial Release Techniques on Pain, Movement, and Function in Patients with Myofascial Pain Syndrome)

  • 최원재;남은정;김현중;이승원
    • PNF and Movement
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    • 제18권2호
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    • pp.245-254
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    • 2020
  • Purpose: The study investigated the effects of extracorporeal shock wave therapy with myofascial release techniques (ESWT+MFR) on pain, movement, and function in patients with myofascial pain syndrome. Methods: Forty participants with upper trapezius trigger points were recruited and randomly allocated to two groups: an experimental group (n = 20) and a control group (n = 20). The experimental group performed the ESWT+MFR, and the control group performed only myofascial release techniques. Each group was treated for 15 minutes, twice a week for four weeks. Pain was assessed using a visual analogue scale and a pressure pain threshold measure. Movement was assessed by cervical range of motion, and cervical and shoulder function were assessed on the Constant-Murley Scale and the Neck Disability Index before and after treatment. Results: The results indicate statistically significant improvements in the two groups on all parameters after intervention as compared to baseline (p < 0.05). As compared to the control group, the experimental group showed statistically significant improvements on the visual analogue scale and pressure pain threshold, cervical range of motion (except rotation), and on the Neck Disability Index (p < 0.05). Conclusion: The ESWT+MFR is more effective than myofascial release techniques for pain, movement, and function in patients with myofascial pain syndrome and would be clinically useful for physical therapists treating myofascial pain syndrome.

신경퇴화 및 지적장애 예방에 관한 고지능검사도구 이용의 실효성 연구 (The Efficiency of Intelligence Quotient Test at Prevention of Mental Retardation and Dementia)

  • 염승민;전상훈;이민기;김다은;양대욱
    • 보건의료산업학회지
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    • 제7권2호
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    • pp.101-111
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    • 2013
  • To develop the Korean-Version-Improvement program for ordinary people, we investigate how Korean-High-Intelligent people use their cognitive function, intellectual capacity and Intelligent Quotient test. Using Mensa iq test, we classify intelligent examination tool into various components; visual, geometrical component and cognitive interpretation component. Also we organized each component, got database of intelligent subjects sample, classified itemized availability. Based on these things, we prove efficiency of intelligent examination tool. We found out that high intelligent people showed high Intelligent Index using visual cognitive stimulation with cognitive function when subjects were exposed to certain situation; solving the problem. This intelligent examination tool is low price and safe and easily carrying out with personal computer. If we develop intelligence quotient examination customized with mental retardation populations, a variety of subjects will improve their cognition with efficiency and inexpensively.

시각특성과 DCT를 이용한 영상부호화에 관한 연구 (A Study on Image Coding using the Human Visual System and DCT)

  • 남승진;최성남;전중남;박규태
    • 한국통신학회논문지
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    • 제17권4호
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    • pp.323-335
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    • 1992
  • 본 논문에서는 인간의 시각특성을 반영한 적응 DCT 영상 부호화에 관하여 연구하였다. 인간의 시각은 특정한 중간 주파수 대역에 가장 민감하며, 저주파 대역과 고주파 대역에 대하여 상대적으로 덜 민감하다. 이러한 특성은 많은 심리시각적 실험을 통하여 MTF(Modulation transfer function)라는 수식으로 모델링되었다. DCT는 공간영역의 에너지를 주파수 영역으로 변환하므로 MTF를 효율적으로 이용할 수 있다. 또한 시각의 공간 마스킹 특성에 의하여 변화가 많은 영역의 잡음은 변화가 적은 영역의 잡음에 비하여 인간의 시각에 덜 민감하다. 제안된 부호화 방법은 시각의 공간주파수 반응 특성을 양자화 행렬로 채택하였으며, 영상의 변화도에 따라 변환 블럭을 차등양자화 함으로써 주관적 화질의 향상을 꾀하였다. 각 블럭의 변화도를 측정하기 위한 방법으로 공간 영역에서 간단한 연산을 행하였으며, 이에 따라 변화가 적은 블럭을 상대적으로 정확하게 양자화하였다. 실험결과 낮은 비트율에서 시각특성을 반영한 제안된 부호화 방법이 주관적으로 우수한 성능을 보임을 확인하였다.

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Which Index for Muscle Mass Represents an Aging Process?

  • Kim, Hyung-Kook;Lee, You Jin;Lee, Young-Kyun;Kim, Hongji;Koo, Kyung-Hoi
    • 대한골대사학회지
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    • 제25권4호
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    • pp.219-226
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    • 2018
  • Background: Although studies and interest in sarcopenia have increased, it is still a matter of debate which muscle mass index better represents the aging process. We compared 3 indices for muscle mass (appendicular skeletal muscle mass [ASM]/weight, $ASM/height^2$, and the body mass index [BMI]-adjusted muscle mass index [ASM/BMI]) to determine which better reflected the aging process in terms of the decline in bone mineral density (BMD), visual acuity (VA), hearing power, renal function, pulmonary function, and handgrip strength. Methods: We performed a retrospective cross-sectional study using the Korea National Health and Nutrition Examination Survey in the Korean population. Between 2008 and 2011, a total of 14,415 men and 17,971 women aged 10 years or older participated in the study. We plotted the changes in the 3 indices of muscle mass and compared these with changes in BMD, VA, hearing power, renal function, pulmonary function, and handgrip strength according to each age group. Results: The ASM/BMI showed similar changes in terms of surrogate markers of the aging process, while the ASM/weight and $ASM/height^2$ showed no correlation. Conclusions: Among muscle indices for sarcopenia, only the ASM/BMI represented the aging process.

Effects of Injection Laryngoplasty with Hyaluronic Acid in Patients with Vocal Fold Paralysis

  • Kim, Geun-Hyo;Lee, Jae-Seok;Lee, Chang-Yoon;Lee, Yeon-Woo;Bae, In-Ho;Park, Hee-June;Lee, Byung-Joo;Kwon, Soon-Bok
    • Osong Public Health and Research Perspectives
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    • 제9권6호
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    • pp.354-361
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    • 2018
  • Objectives: The purpose of this study was to explore the effects of injection laryngoplasty (IL) with hyaluronic acid in patients with vocal fold paralysis (VFP). Methods: A total of 50 patients with VFP participated in this study. Pre- and post-IL assessments were performed, which included analyzing the sustained vowel /a/ phonation, and the patient reading 1 Korean sentence from the "Walk" passage that comprised 25 syllables in 10 words. To investigate the effect of IL on vocal fold function, acoustic analysis (acoustic voice quality index, cepstral peak prominence, maximum phonation time, speaking fundamental frequency) was conducted and auditory-perceptual (grade and overall severity), visual judgment (gap), and self-questionnaire (voice handicap index-10) assessments were performed. Results: The patients with VFP showed statistically significant differences between pre-and post-IL assessments for acoustic and auditory-perception, visual judgment, and self-questionnaire assessments. Conclusion: The patients with VFP showed positive change in vocal fold function between pre- and post-IL measurements. The findings showed that IL with hyaluronic acid is an effective method to improve vocal fold function in patients with VFP.

동작관찰과 시각적 되먹임 융합 운동이 머리전방자세와 둥근어깨의 정렬, 통증과 기능에 미치는 영향 (The Effects of the Action Observation and Visual Feedback Convergence Exercise on the Alignment, Pain and Function of Forward Head Posture and Round Shoulder Posture)

  • 강효정;양회송
    • 한국융합학회논문지
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    • 제9권12호
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    • pp.123-128
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    • 2018
  • 본 연구는 머리전방자세와 둥근어깨자세에 대한 일반 운동과 동작관찰, 시각적 되먹임의 효과를 알아보고자 한다. 머리전방자세와 둥근어깨자세를 가진 24명으로 하였으며, 일반 운동군(8명), 동작관찰군(8명), 시각적 되먹임군(8명)으로 무작위 배분하였다. 모든 운동군은 주 3회, 총 4주간 운동하였다. 운동 전 후 머리척추각(CVA), 둥근어깨자세(RSP), 시각적 상사척도(VAS), 경부장애지수(NDI)를 평가하였다. 연구결과 CVA는 일반 운동군과 동작관찰군에서 유의한 변화를 보였으며, RSP, VAS, NDI의 경우 모든 운동군에서 유의한 변화를 보였다. 운동군 간 변화량 비교에서는 VAS에서 동작관찰군이 일반 운동군과 시각적 되먹임군보다 큰 변화량을 보였다. 본 연구결과 동작관찰이 머리전방자세와 둥근어깨자세의 개선에 효과가 있을 것이라고 사료된다.