• Journal of Korea Society of Industrial Information Systems
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• v.13 no.3
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• pp.1-8
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• 2008

In the event of a traffic accident, a fire accident, or a criminal act, anyone will be able to capture these important moments and use authentic photographs for evidence purposes. Digital watermarking is able to ensure that the digital photographs taken from a particular camera-phone are authentic and indeed. This paper presents a blind image watermarking technique for digital phone camera. This method is based on singular value decomposition (SVD) and wavelet decomposition. Experimental results show that the proposed technique performs well in security and robustness against JPEG compression.

• Archives of Plastic Surgery
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• v.37 no.4
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• pp.499-530
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• 2010

Purpose: Lateral osteotomy is an essential step in the correction of nasal bony asymmetry. Direct visualization allows accurate repositioning of the nasal bones compared to blind techniques, which require precision and manual dexterity. We propose direct visualization procedures in open corrective rhinoplasty. Methods: The technique was used on 16 patients. All patients underwent open rhinoplasty with a columellar incision. The marginal incisions were extended on either side to allow access to the piriform aperture. A double hook was used to caudally retract the lower lateral cartilages and the fibrous connections between the upper and lower lateral cartilages were released until the piriform aperture was visualized. Through the incision, lateral osteotomy was performed using a reciprocating saw at that time with direct visualization. Additional procedures including augmentation rhinoplasty, hump resection, septoplasty and tip plasty were performed simultaneously. Results: This method provided excellent exposure to the lateral nasal bones and allowed the lateral osteotomy to be carried out precisely using the reciprocating saw. Conclusion: This extended open rhinoplasty method is suitable for most individuals, allowing a wide surgical field.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.2
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• pp.113-119
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• 2006

Coronary artery disease is a loading cause of morbidity and mortality across the world. Percutaneous coronary intervention has become the major technique of revascularization. However, restenosis remains a major limitation of this procedure. Recently the need for repeat intervention due to restenosis, the most vexing long-term failure of percutaneous coronary intervention, has been significantly reduced owing to the introduction of two major advances, intracoronary brachytherapy and the drug-eluting stents. Intracoronary brachytherapy has been employed in recent years to prevent restenosis lesions with effective results, principally in in-stent restenosis. Restenosis is generally considered as au excessive form of normal wound healing divided up in precesses: elastic recoil, neointimal hyperplasia, and negative vascular remodeling. Restenosis has previously been regarded as a proliferative process in which neointimal thickening, mediated by a cascade of inflammatory mediators and other factors, is the key factor. Ionizing radiation has been shown to decrease the proliferative response to injury in animal models of restenosis. Subsequently, several randomized, double blind trials have demonstrated that intracoronary brachytherapy can reduce the rates of both angiographic restenosis and clinical event rates in patients undergoing percutaneous coronary intervention for in stent restenosis. Some problems, such as late thrombosis and edge restenosis, have been identified as limiting factors of this technique. Brachytherapy is a promising method of preventing and treating coronary artery restenosis.

• The KIPS Transactions:PartB
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• v.12B no.4 s.100
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• pp.443-450
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• 2005

Digital fingerprinting is a contents-protection technique, where customer information is inserted into digital contents. Fingerprinted contents undergo various attacks. Especially, attackers can remove easily the inserted fingerprint by collusion attacks, because digital fingerprinting inserts slightly different codes according to the customers. Among collusion attacks, averaging attack is a simple, fast, and efficient attack. In this paper, we propose a video fingerprinting system that is robust to the averaging attack. In order to achieve code efficiency and robustness against the averaging attack, we adopt anti-collusion code (fingerprint code) from GD-PBIBD theory. When the number of users is increased, the size of fingerprint code also grows. Thus, this paper addresses a zero-based code modulation technique to embed and detect this fingerprint code efficiently. We implemented a blind video fingerprinting system based on our proposed technique and performed experiments on various colluding cases. Based on the results, we could detect most of colluders. In the worst case, our scheme could trace at least one colluder successfully.

• Journal of Veterinary Science
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• v.22 no.2
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• pp.22.1-22.9
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• 2021

Background: Standing surgery in horses combining intravenous sedatives, analgesics and local anaesthesia is becoming more popular. Ultrasound guided (USG) peribulbar nerve block (PB) has been described in dogs and humans for facial and ocular surgery, reducing the risk of complications versus retrobulbar nerve block (RB). Objective: To describe a technique for USG PB in horse cadavers. Methods: Landmarks and PB technique were described in two equine cadaver heads (Phase 1), with computed tomography (CT) imaging confirming contrast location and spread. In Phase 2, ten equine cadaver heads were randomised to two operators naive to the USG PB, with moderate experience with ultrasonography and conventional "blind" RB. Both techniques were demonstrated once. Subsequently, operators performed five USG PB and five RB each, unassisted. Contrast location and spread were evaluated by CT. Injection site success was defined for USG PB as extraconal contrast, and for RB intraconal contrast. Results: Success was 10/10 for USG PB and 0/10 for RB (p < 0.001). Of the RB injections, eight resulted in extraconal contrast and two in the masseter muscle (p = 0.47). Conclusions: The USG PB had a high injection site success rate compared with the RB technique; however, we cannot comment on clinical effect. The USG technique was easily learnt, and no potential complications were seen. The USG PB nerve block could have a wide application for use in horses for ocular surgeries (enucleations, eyelid, corneal, cataract surgeries, and ocular analgesia) due to reduced risk of iatrogenic damage. Further clinical studies are needed.

• Journal of Korean Physical Therapy Science
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• v.28 no.3
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• pp.66-75
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• 2021

Background: The purpose of this study is to investigate the effect of muscle energy technique and stretching on pain and pressure pain fear-avoidance beliefs questionnaire in patients with chronic back pain aged 30~40 years. Design: Pretest-Posttest design: single blind. Methods: The subjects of this study were 30, 22 males and 8 females between the ages of 30 and 40 with chronic back pain. Each group consists of three groups of 10 people. Changes in back pain were observed using Korean version of Oswestry Disability Index (K-ODI), visual analogue scale (VAS), and fear-avoidance beliefs questionnaire (FABQ). And the change in tenderness was observed using digital pressure statistics. Changes between groups after 3 weeks were compared with those before the experiment using one way ANOVA to determine the changes after 3 weeks. And the change within the group was investigated using the paired t-test. Results: As a result of the experiment, there were significant differences in the group changes in K-ODI, VAS, FABQ, and pressure pain (p<0.05). And there was a significant difference in all items after 3 weeks compared to before the experiment (p<0.05). Conclusion: In patients with chronic back pain, the muscle energy technique and stretching gave a significant difference in pain and pressure pain, fear-avoidance beliefs questionnaire changes. And this result suggests the possibility of providing basic data for future research and clinical physiotherapy intervention.

• Medical Lasers
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• v.9 no.2
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• pp.166-171
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• 2020

Background and Objectives Melasma is an acquired pigmentary disorder characterized by brown or dark brown colored macules and patches which mostly involve the face. Compared to nanosecond lasers, picosecond lasers have fewer adverse effects on surrounding tissues and give better results for melanin fragmentation. The purpose of this study was to evaluate the efficacy of the pico-toning technique using a low fluence 1,064-nm Nd:YAG laser on melasma patients. Materials and Methods This study is a retrospective analysis of melasma cases treated using the pico-toning technique from June 2017 to November 2020. Based on photographic images, the modified Melasma Area and Severity Index (mMASI) score was blind evaluated by two independent plastic surgeons. Patient satisfaction was assessed through a 5-point Likert scale questionnaire after treatment sessions. All adverse effects and complications were reviewed based on medical records. Results A total of 23 patients were included in the study. The mMASI scores for baseline and 2 months after the last procedure were 5.1 ± 1.4 and 2.6 ± 0.4, respectively. The mean mMASI score reduced significantly after the treatment session (p < 0.05). The patient satisfaction score with the procedure was 3.8 ± 1.0. The subject satisfaction score and difference in the mMASI score before the procedure and 2 months after the last procedure showed a significant correlation. Adverse effects observed in this study were erythema (n = 1) and edema (n = 1). Conclusion The results of the study show that the pico-toning technique is effective in Asian patients with melasma. We believe that safety was enhanced by using low fluence, and thus better results were achieved with fewer adverse effects.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.2
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• pp.11-20
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• 2010

In this study, the effects of stand height growth on GIS-based viewshed analysis were investigated. DSM was created by combining stand height layers on DEM using map algebra functions. In developing the tree height layers, the digital forest-type maps, forest site maps and stand yield tables of Korea Forest Research Institute were used. The time horizon for viewshed analysis were 40 years. Two viewpoints in crossings of downtown for viewshed analyses were chosen using a projective mapping technique. The effects of tree height growth over time on visibility were measured in terms of the depth of blind areas and the area of visible regions. The results of viewshed analyses show that 17% of visible regions is reduced when we use DSM instead of DEM. As the tree height grows, the visibility gets worse and worse and the depth of blind area increases.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.7A
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• pp.603-610
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• 2005

Beam-forming method based on the estimated channel information at the base station degrade the performance mismatching directional vector in case of systems which Frequency Division Duplex (FDD) center frequency of uplink and downlink are different. Also blind estimation technique which is to obtain directional vector of reverse link through received signal has disadvantage of hardware complexity increase. To solve these problems, in present paper, a smart antenna algorithm which is to improve the beam-forming complexity increase due to user number by appling the spatial fourier transform to be able to beam- forming toward a wanted direction through adjusting a obtained uplink weight function by estimating Angle-of-Arrival (AoA) to the competable form at the downlink is proposed. The proposed algorithm is integrated to the CDMA downlink transmitter and simulations are performed to confirm the performance as frame error rate at the receiver. As a result, the beam forming effect is confirmed and the performance gain with the proposed algorithm is comparable to ordinary smart antenna system.

• Spatial Information Research
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• v.21 no.3
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• pp.31-43
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• 2013

Although the vector map data possesses much higher values than other types of multimedia, the data copyright and the protection against illegal duplication are still far away from the attention. This paper proposes a novel watermarking technique which is both robust to diverse attacks and optimized to a vector map structure. Six approaches are proposed for the design of the watermarking algorithm: point-based approach, building a minimum perimeter triangle, watermark embedding in the length ratio, referencing to the pixel position of the watermark image, grouping, and using the one-way function. Our method preserves the characteristics of watermarking such as embedding effectiveness, fidelity, and false positive rate, while maintaining robustness to all types of attack except a noise attack. Furthermore, our method is a blind scheme in which robustness is independent of the map data. Finally, our method provides a solution to the challenging issue of degraded robustness under severe simplification attacks.