• Physical Therapy Rehabilitation Science
• /
• v.11 no.4
• /
• pp.478-487
• /
• 2022

Objective: This study was conducted to analyze the effect of wearable complex muscle support system on energy efficiency during walking in elderly. Design: Cross sectional study Methods: Twenty healthy elderly participated in this study. All subjects performed a 6 minuteswalk test(6MWT) and stair climbing test in dual, slack and no suit conditions. In each condition, oxygen consumption(VO₂), metabolic equivalents(METs), energy expenditure measures(EEm), physiological cost index(PCI), walking velocity and heartrate were measured. Through repeated measured ANOVA, it was investigated whether there was a statistically significant difference in the measurement results between the three conditions. Results: In over-ground walking, VO₂, METs and EEm showed significant differences between no suit and slack conditions(p<0.05). In stair climbing, VO₂ showed significant difference between slack and dual conditions(p<0.05). Also, METs and EEm showed significant differences between no suit and slack, and between slack and dual conditions(p<0.05). Conclusions: Wearing the wearable complex muscle support system for elderly does not have much benefit in energy metabolism efficiency in over-ground, but there is a benefit in stair walking.

• The Journal of the Acoustical Society of Korea
• /
• v.23 no.4E
• /
• pp.125-133
• /
• 2004

In this paper, we propose a critical banded wavelet packet-based spectral subtraction for speech enhancement. Critical banded wavelet packet, which reflects the human auditory system, may lead to minimization of intelligibility loss and quality improvement of the enhanced speech in the spectral domain, when combined with an appropriate spectral subtraction gain function. The proposed method shows better performance than the conventional one in comparative assessments. We also show that, for effective evaluation of enhanced speech, it is essential to consider the characteristics of speech quality measures.

• Journal of Korea Multimedia Society
• /
• v.21 no.2
• /
• pp.108-116
• /
• 2018

In this paper, we propose an image enhancement method based on Multi-Scale Retinex theory that designs Unsharp Masking Filter (UMF) and emphasizes the contrast ratio adaptively. Unsharp Masking (UM) technique emphasizes image sharpness and improves contrast ratio by adding high frequency component to the original image. The high frequency component is obtained by differentiating between original image and low frequency image. In this paper, we present how to design an UMF kernel and to adaptively apply it to increase the contrast ratio according to multi-scale retinex theory which resembles human visual system. Experimental results show that the proposed method has better quantitative performance indexes such as PSNR, ambe & SSIM and better qualitative feature like halo artifact suppression.

• Proceedings of the KIEE Conference
• /
• 2004.11c
• /
• pp.175-177
• /
• 2004

The current JPEG-2000 standard is a wavelet based scheme because wavelet transform have some advantages compare to DCT transform. In compressed images, there are some image degradation factors like contrast distortion by Quantization process. This factor is very important to HVS (Human Visual System). Therefore, In this paper, we propose a new algorithm for contrast enhancement using the properties of wavelet coefficients. This algorithm is processed in the wavelet domain and so it can be applied efficiently to JPEG-2000.

• Journal of the Korean Institute of Navigation
• /
• v.21 no.1
• /
• pp.119-128
• /
• 1997

Nowadays, many satellites regularly produce digital multispectral images of the earth's surface. Multispectral images may be displayed as color pictures by selecting three components for assignment to the primary colors. It is desired to enhance these images to generate a display picture that are representativde of their features. in this paper, a false color image processing algorithm is proposed for the purpose of enchancement of the multispectral images based on the human perception. The mean of each primary component is transformed to equalo. Intensity and saturation are enhanced by modified piecewise linear contrast strectching and saturation enhancement method. The proposed method has been successfully applied the LANDSAT TM image and shows good enhancement.

• BMB Reports
• /
• v.49 no.10
• /
• pp.566-571
• /
• 2016

Forskolin (FSK), an adenylyl cyclase activator, has recently been shown to enhance nucleotide excision repair (NER) upon UV exposure. However, our study revealed that this effect was detected in human skin epithelial ARPE19 cells only in growing cells, but not in non-cycling cells. When the cells were grown at low density (70% confluence), FSK was capable of stimulating cAMP responsive element binding (CREB) phosphorylation, a marker for FSK-stimulated PKA activation, and resulted in a significant increase of NER activity compared to control treatment. However, cells grown under 100% confluent conditions showed neither FSK-induced CREB phosphorylation nor the resulting NER enhancement. These findings indicate that cellular growth is critical for FSK-induced NER enhancement and suggest that cellular growth conditions should be considered as a variable while evaluating a reagent's pharmacotherapeutic efficacy.

• Journal of Korea Multimedia Society
• /
• v.6 no.6
• /
• pp.977-984
• /
• 2003

In this paper, we propose an image enhancement algorithm for panoramic infrared image. This method divides a panoramic infrared image into disjoint subimages and performs the contrast stretch for subimages using statistical characteristics of each subimage. But these cause blocking artifact in boundary regions of neighboring subimages which different to the statistical characteristic. To remove blocking artifact, we perform the contrast stretch for subimage's boundary regions using statistical characteristics of horizontally neighboring subimages. Experimental results show that the proposed method effectively improves their appearance to human viewers.

• Journal of Korean Neurosurgical Society
• /
• v.53 no.6
• /
• pp.380-382
• /
• 2013

We report a case of fatal duret hemorrhage (DH) in a patient with acute tentorial subdural hematoma and bilateral chronic subdural hematoma along the cerebral hemispheres. Preoperative CT angiography (CTA) revealed prominent parenchymal enhancement in the ventral pontomesencephalic area. After burr-hole drainage, a large hemorrhage developed in this area. The parenchymal enhancement in the CTA may reflect the pontomensencephalic perforating vessel injury, and may be a sign of impending DH of acute transtentorial downward herniation. Previous use of aspirin and warfarin might have potentiated the process of DH and increase the extent of the bleed.

• Electronics and Telecommunications Trends
• /
• v.34 no.4
• /
• pp.108-116
• /
• 2019

Electro-active polymers and dielectric elastomers have many intriguing properties that enable smart interfaces and electrically tunable optical systems, such as haptic feedback devices, artificial muscles, and expansion-tunable optical elements. These device classes are of great interest owing to their promising roles in next-generation technologies including virtual or augmented reality, human sensing and muscular enhancement, and artificial skins. In this report, we review basic principles, current state-of-the-art techniques, and future prospects of electro-active and dielectric elastomer technology. We describe chemical and physical properties of the most promising polymer substances, essential elementary architectures for artificial muscle-like functionalities, and their applications to haptic interfaces, muscular enhancement, and focus-tunable optical elements.

• Korean Journal of Cognitive Science
• /
• v.25 no.1
• /
• pp.51-71
• /
• 2014

This paper presents an image enhancement method in real road traffic scenes. The images captured by the camera on the car cannot keep the color constancy as illumination or weather changes. In the real environment, these problems are more worse at back light conditions and at night that make more difficult to the applications of the vision-based intelligent vehicles. Using the existing image enhancement methods without considering the position and intensity of the light source and their geometric relations the image quality can even be deteriorated. Thus, this paper presents a fast and effective method for image enhancement resembling human cognitive system which consists of 1) image preprocessing, 2) color-contrast evaluation, 3) alpha blending of over/under estimated image and preprocessed image. An input image is first preprocessed by gamma correction, and then enhanced by an Automatic Color Enhancement(ACE) method. Finally, the preprocessed image and the ACE image are blended to improve image visibility. The proposed method shows drastically enhanced results visually, and improves the performance in traffic sign detection of the vision based intelligent vehicle applications.