• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.6
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• pp.149-158
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• 2005

This paper proposed a blind watermarking method for video contents which satisfies both the invisibility and the robustness to attacks to prohibit counterfeiting, modification, illegal usage and illegal re-production of video contents. This watermarking algorithm targets MPEG compression system and was designed to control the amount of watermarking to be inserted according to the adaptive quantization scale code to follow the adaptive quantization of the compression system. The inserting positions of the watermark were chosen by considering the frequency property of an image and horizontal, vertical and diagonal property of a $8{\times}8$ image block. Also the amount of watermarking for each watermark bit was decided by considering the quantization step. This algorithm was implemented by C++ and experimented for invisibility and robustness with MPEG-2 system. The experiment results showed that the method satisfied enough the invisibility of the inserted watermark and robustness against attacks. For the general attacks, the error rate of the extracted watermark was less than $10\%$, which is enough in robustness against the attacks. Therefore, this algorithm is expected to be used effectively as a part in many MPEG systems for real-time watermarking, especially in the sensitive applications to the network environments.

• The Journal of the Acoustical Society of Korea
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• v.32 no.1
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• pp.71-78
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• 2013

This paper describes a multiple audio watermarking using Quantization Index Modulation (QIM) on frequency phase and magnitude response. Proposed embedding procedure is composed of two stage. At the first stage, the watermark is embedded on the frequency phase response using QIM. In the second stage, the watermark is embedded using adaptive QIM with the step-size that is adaptively determined using the maximum value of the frequency magnitude response of every frame. The watermark is extracted by calculating the Euclidean distance as the blind detection. The proposed method is robust against most of attacks of audio watermark benchmarking. For the Fourier attacks, the proposed method shows over 95% recovery rate.

• Journal of Broadcast Engineering
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• v.23 no.4
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• pp.484-494
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• 2018

The uniform motion blur removing algorithm of Cho et al. has the problem that the edge region of the image cannot be restored clearly. We propose the effective algorithm to overcome this problem by using shock filter that reconstructs a blurred step signal into a sharp edge, and convolutional neural network (CNN) that learns by extracting features from the image. Then uniform motion blur kernel is estimated from the latent sharp image to remove blur in the image. The proposed algorithm improved the disadvantages of the conventional algorithm by reconstructing the latent sharp image using shock filter and CNN. Through the experimental results, it was confirmed that the proposed algorithm shows excellent reconstruction performance in objective and subjective image quality than the conventional algorithm.

• Explosives and Blasting
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• v.26 no.2
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• pp.45-51
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• 2008

Fireworks display is called as younwha in korean, pokjuk in chinese, hanabi in japanese and fireworks display in English. Fireworks is a kind of art calling as engineering art program that presents its artistic sense by making up light, sound, heat, form, smoke, smoke screen, time delay and kinetic energy etc. which are made by combustion and deflagrations of explosives. Korea's fireworks skill is world class. In 1980s, we already developed the skills. After 2010 year, It would develop as Nano-biotechnology considering its environmental safety passing by 1990s' grow fully step. After pleasant fireworks, it requires a environmental pollution control measure, ability of emergency state control, management of storing place, a blind shell and waste disposal and citizenship elevation etc. This paper indicated around fireworks the present conditions, environmental pollution buzz, direction of development and plan.

• Journal of Microbiology and Biotechnology
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• v.21 no.7
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• pp.766-775
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• 2011

We investigated the effect of high molecular weight polygamma- glutamic acid (hm ${\gamma}$-PGA) on adiposity and lipid metabolism of rats in the presence of an obesity-inducing diet. Thirty-two Sprague-Dawley rats were fed either a normal-fat (11.4% kcal fat, NFC) or high-fat (51% kcal fat, HFC) diet. After 5 weeks, half of each diet-fed group was treated with hm ${\gamma}$-PGA (NFP or HFP) for 4 weeks. The HFC group had significantly higher body weight, visceral fat mass, fasting serum levels of total cholesterol, LDL cholesterol, and leptin, and lower serum HDL cholesterol level compared with those of the NFC group (p < 0.05). Treatment with hm ${\gamma}$-PGA decreased body weight gain and perirenal fat mass (p<0.05), fasting serum total cholesterol, and mRNA expression of glucose-6- phosphate dehydrogenase (G6PD), regardless of dietary fat contents (p < 0.01). However, hm ${\gamma}$-PGA increased serum HDL cholesterol in the HFC group (p < 0.05). In vitro, 3-hydroxy-3-methylglutaryl coenzyme-A (HMGCoA) reductase activity was suppressed by the addition of hm ${\gamma}$-PGA. In agreement with observations in animal study, the supplementation of hm ${\gamma}$-PGA (150 mg/day) to 20 female subjects in an 8-week double-blind, placebocontrolled study resulted in a tendency to decrease total cholesterol and LDL cholesterol concentrations. We thus conclude that dietary supplementation of hm ${\gamma}$-PGA may act as a hypocholestrolemic agent, secondary to its inhibitor effect on HMG-CoA reductase, and decrease abdominal adiposity by decreasing hepatic lipogenesis. The present study is an important first step in establishing the effect of hm ${\gamma}$-PGA on cholesterol levels in rats and humans.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.5
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• pp.441-449
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• 2021

Background: The efficacy of local anesthesia decreases in patients with symptomatic irreversible pulpitis. Therefore, it was proposed that the use of premedication with an anti-inflammatory drug might increase the success rate of pulpal anesthesia in mandibular posterior teeth with vital inflamed pulp. Methods: One hundred thirty-four patients who were actively experiencing pain willingly participated in this study. The Heft Parker (HP) visual analog scale (VAS) was used to record the initial pain intensity. Patients were randomly allocated to receive a placebo, 10 mg of ketorolac, and 650 mg of paracetamol. The standard inferior alveolar nerve block (IANB) was administered to all patients using 2% lidocaine with 1:200,000 adrenaline after one hour of medication. After 15 min, the patient was instructed to rate the discomfort during each step of the treatment procedure, such as access to remaining dentin, access to the pulp chamber, and during canal instrumentation on the HP VAS. IANB was considered successful if the patient reported no or mild pain during access preparation and instrumentation. Moderate or severe pain was classified as a failure of IANB and another method of anesthesia was used before continuing the treatment. Results: The rate of successful anesthesia in the placebo, paracetamol, and ketorolac groups was 29%, 33%, and 43%, respectively, and no statistically significant difference was found between the groups. Conclusion: Preoperative administration of paracetamol or ketorolac did not significantly affect the success rate of IANB in patients with irreversible pulpitis. No significant difference was observed between the paracetamol and ketorolac groups.

• Journal of Acupuncture Research
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• v.39 no.2
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• pp.115-121
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• 2022

Background: To evaluate the efficacy and safety of Phellinus linteus (PL) extract for the treatment of knee osteoarthritis (KOA) a pilot clinical study was performed. Methods: There were 24 patients with KOA who enrolled in this double-blind, randomized, controlled, clinical trial. There were 3 groups: PL 1,000 mg/day (PL 1,000), PL 1,500 mg/day (PL 1,500), and dextrin 3,000 mg/day (placebo). Patients took capsules twice a day, 3 capsules at a time, over 8 weeks. Patients were monitored prior to treatment (Visit 1: Week 0), and followed up every 4 weeks (Visit 2: Week 4 and Visit 3: Week 8) where outcome measurements were taken. The primary outcome measure was the score from the Korean version of the Western Ontario and McMasters Universities from baseline to Week 8. The secondary outcomes were measurements from the visual analog scale, quality of life scale, erythrocyte sedimentation, and c-reactive protein. Adverse events were recorded at every visit. Results: The Korean version of the Western Ontario and McMasters Universities score showed the greatest improvement in symptoms of KOA in the PL 1,500 group compared with the placebo group. The erythrocyte sedimentation tended to decrease in the PL 1,500 group compared with the placebo group (which was within the normal range). The visual analog scale score decreased in all groups, with no significant differences between groups. No adverse events related to PL were reported. There were no abnormal hematological or physical findings. Conclusion: This pilot clinical trial was the first step to assess the efficacy and safety of PL used in the treatment of patients with KOA.

• Journal of Service Research and Studies
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• v.13 no.1
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• pp.186-200
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• 2023

This study aims to improve the usability of the white cane, which is walking equipment that most local visually impaired people use and carry when going out, and to contribute to the prevention of safety accidents and the walking rights of visually impaired people by providing improvement and resolution measures for the problems identified. Also, this study is a study on the visually impaired, primarily targeting the 1st to 2nd degree visually impaired people, who cannot go out on their own without walking equipment such as a white cane, corresponding to 20% among approximately 250,000 blind and low vision people in the Korean population. In the study process, the concept has been developed from the user's point of view in order that the white cane becomes a real help in the walking step of the visually impaired and the improvement of usability of the white cane, the main walking equipment for the visually impaired, are done by problem identification through the Double Diamond Model of Design Thinking (Empathize → Define → Ideate → Prototype → Test (verify)). As a result of the investigation in the process of Empathy, a total of five issues was synthesized, including an increase in the proportion of the visually impaired people, an insufficient workforce situation to help all the visually impaired, an improvement and advancement of assistive devices essential for the visually impaired, problems of damage, illegal occupation, demolition, maintenance about braille blocks, making braille block paradigms for the visually impaired and for everyone. In Ideate and Prototype steps, situations derived from brainstorming were grouped and the relationship were made through the KJ method, and specific situations and major causes were organized to establish the direction of the concept. The derived solutions and major functions are defined in four categories, and representative situations requiring solutions and major functions are organized into two user scenarios. Ideas were visualized by arranging the virtual Persona and Customer Journey Map according to the situation and producing a prototype through 3D modeling. Finally, in the evaluation, the final concept derived is a device such a smart cane for guidance for the visually impaired as ① a smart cane emphasizing portability + ② compatibility with other electronic devices + ③ a product with safety and convenience.

• Journal of Korean Physical Therapy Science
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• v.18 no.2
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• pp.51-62
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• 2011

Purpose: The purpose of this study was to investigate the effect of microcurrent on fatigue of muscles in people who were flat-footed during gait. Methods: 10 flat-footed university students volunteered to participate in this study. 10 flat-footed subjects were divided into 2 groups, one group was experimental group of 5subjects(This group put on microcurrent induction shoes but the subjects were not able to feel the current.) and the other group was the control group of 5subjects(This group put on the general shoes which were similar in shape but microcurrent was not induced.) to perform double blind test and random sampling. Their gait muscle fatigue of 6 regions (vastus medialis, gastrocnemius, tibialis anterior, biceps femoris, erector spinae, and rectus abdominis muscle.) was measured by EMG MP150, Delsys Inc Boston, USA during walking and then they carried out the Harvard step with a platform (It was a arbitrarily made wooden platform of 100cm long, 50cm wide, 60cm high. They carried out climbing it for one second and descending it for one second by using the Metronome program, total 5minutes) for 5minutes. Right after that, the subjects walked on a treadmill at a speed of 4km/h for 10minutes and then their gait muscle fatigue of 6regions was assessed while they were walking on the ground as equally as before exercise. Results: The experimental group has resulted in lower average differences in gait muscle fatigue before and after exercise than those of the control group average 12.24Hz(P=0.009) at vastus medialis, average 8.52Hz(P=0.016) at gastrocnemius, average 9.16Hz(P=0.009) at tibialis anterior, average 8.66Hz(P=0.047) at biceps femoris, average 7.53Hz(P=0.016) at erector spinae, and average 7.80Hz(P=0.047) at rectus abdominis. All of the assessments of muscles have shown significant difference statistically. Conclusions: This result has shown that the use of micro current could decrease gait muscle fatigue of flat-footed people. It is recommended to use a microcurrent to reduce their gait muscle fatigue.

• Journal of Broadcast Engineering
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• v.21 no.6
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• pp.845-860
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• 2016

This paper proposes a digital watermarking scheme to protect the ownership of the freeview 2D or 3D image such that the viewer watches the image(s) by rendering a arbitrary viewpoint image(s) with the received texture image and its depth image. In this case a viewpoint change attack essentially occurs, even if it is not malicious. In addition some malicious attacks should be considered, which is to remove the embedded watermark information. In this paper, we generate a depth variation map (DVM) to find the locations less sensitive to the viewpoint change. For each LH subband after 3-level 2DDWT for the texture image, the watermarking locations are found by referring the DVM. The method to embed a watermark bit to a pixel uses a linear quantizer whose quantization step is determined according to the energy of the subband. To extract the watermark information, all the possible candidates are first extracted from the attacked image by considering the correlation to the original watermark information. For each bit position, the final extracted bit is determined by a statistical treatment with all the candidates corresponding that position. The proposed method is experimented with various test images for the various attacks and compared to the previous methods to show that the proposed one has excellent performance.