• International Journal of Computer Science & Network Security
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• v.23 no.4
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• pp.85-94
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• 2023

Image halftoning is a technique for varying grayscale images into two-tone binary images. Unfortunately, the static representation of an image-half toning, wherever each pixel intensity is combined by its local neighbors only, causes missing subjective problem. Also, the existing noise causes an instability criterion. In this paper an image half-toning is represented as a dynamical system for recognizing the global representation. Also, noise is reduced based on a probabilistic model. Since image half-toning is considered as 2-D matrix with a full connected pass, this structure is recognized by the dynamical system of Cellular Neural Networks (CNNs) which is defined by its template. Bayesian Rough Sets is used in exploiting the ideal CNNs construction that synthesis its dynamic. Also, Bayesian rough sets contribute to enhance the quality of the halftone image by removing noise and discovering the effective parameters in the CNNs template. The novelty of this method lies in finding a probabilistic based technique to discover the term of CNNs template and define new learning rules for CNNs internal work. A numerical experiment is conducted on image half-toning corrupted by Gaussian noise.

• Medical Lasers
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• v.10 no.1
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• pp.45-48
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• 2021

Background and Objectives Among the numerous available therapies, the usefulness of laser treatment has been proven in melasma, especially for refractory to topical agents or chemical peels. This study evaluated the effectiveness of 694-nm wavelength fractional toning ruby laser in melasma presenting on the malar area. Materials and Methods This was a retrospective study of 40 melasma patients treated with 694-nm wavelength ruby fractional toning laser for a total of 8 cycles at intervals of 2 to 3 weeks. Two independent investigators assessed the photographic findings and evaluated the severity of melasma by applying the Melasma Severity Scale (MSS). Subject satisfaction score was also surveyed at every visit. Results After the 4th treatment, subjects were continuously satisfied with their results. At the 8th visit and 1-month after the last treatment, MSS was determined to be significantly improved as compared to the first visit. One case of minor hypopigmentation was reported, but was resolved after one month. Conclusion Application of 694-nm wavelength fractional toning ruby laser for treating melasma on the malar area showed significant improvement in the MSS. Moreover, the treatment could be repeatedly applied, with low complication rate and significant patient satisfaction.

• 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.

• Medical Lasers
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• v.10 no.1
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• pp.49-51
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• 2021

The perioral region, which is one of the most conspicuous parts of the face, plays a significant role in interpersonal communication. However, the perioral region is highly susceptible to scarring and pigmentation and is difficult to treat. The causes of perioral hyperpigmentation are many, including physiologic reasons, systemic diseases, drugs, and infections. In the treatment of perioral hyperpigmentation, the cause of the disease must be diagnosed first. Management includes lifestyle modifications such as reducing the UVA exposure time, use of topical treatments including hydroquinone and retinoids, and physical therapy including laser therapy. We report a case of perioral hyperpigmentation treated with 1,064-nm Q-switched neodymium:yttrium-aluminum-garnet laser toning.

• Journal of Conservation Science
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• v.37 no.1
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• pp.1-12
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• 2021

In the digital era, large archives of information and Internet accessibility make information search, including image search, easier and affordable, even from remote locations. Information transmission and sharing can be performed instantly, at any moment. In the case of images, there are risks of transmitting and recklessly sharing intentionally modified images. Such modified images can also be transmitted and used as an additional source of information by followers. In this study, historical portraits of Yu Kil-Chun are shown, who was the first Korean student to study in both Japan and the United States. He was an intellectual, writer, politician, and independence activist of Korea's late Joseon Dynasty. Using image processing software, the portrait images were compared to investigate aging effects and artificial modifications. Statistics of red (R), green (G), blue (B), and L^*, a^*, and b^* values of every pixel in the selected identical areas of the portraits were compared to identify possible causes of variations, including aging effects and artificial modifications. Sepia toning, used in black and white photographs until the 1930s, and modern digital sepia toning can be very confusing owing to their aging effects. The importance of preservation of physical copies and preservation of context (interconnections between data and between documents) is discussed from archiving and conservation science perspectives.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.2
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• pp.92-98
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• 2003

A rate gyroscope has been used popularly to measure the angular motion of a given vehicle using a symmetric rotor spinning rapidly about its symmetry axis. Since the rapid rotation is required in this type of gyroscope, the motor has been used to make the rotor spin, so that it results in a heavy configuration. The toning-fork gyroscope has been developed to avoid this problem, which utilizes a Coriolis coupling term and vibration about one axis. Due to the Coriolis effect, the vibration of one axis is transferred to other axis when the angular motion along the vibrating axis is given to the system. The concept of a tuning-fork gyroscope was recently realized using MEMS techniques. However, the dynamic characteristics of the tuning-fork gyroscope has not been discussed in detail. In this study. we derived the equations of motion for the tuning-fork type gyroscope using the energy approach and investigated the dynamic characteristics by means of numerical analysis.

• Journal of Conservation Science
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• v.35 no.5
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• pp.416-429
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• 2019

Bongchae is primarily employed for toning, which is the last step in the conservation treatment of paper's cultural properties. The objective of this study is to identify the coloring patterns of four types of Bongchae(Bonram, Gamboge, Yeonji, and Daeja) and determine the associated color change patterns through accelerated aging experiments. By examining the coloring patterns, it is observed that Yeonji, Bonram, and Daeja are painted as particles, whereas Gamboge indicates a close state of coating. Results obtained from X-ray diffraction analysis of Bongchae indicate that the presence of quartz, calcite, and pyrophyllite can be equally detected in Bonram, Yeonji, and Daeja. Additionally, the presence of goethite is also detected in Daeja. Gamboge becomes discolored from yellow to orange color during wet thermal aging, and Gamboge and Yeonji become decolorized during UV irradiation aging. Hence, cultural properties of paper colored with Gamboge can be predicted to become discolored to orange color by alkalis and can be darkened by UV rays because the decolorization of Gamboge and Yeonji occurs preferentially.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.597-602
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• 2006

In this paper, a proper support tuning method is established by identifying the dynamic characteristics of the machine, the floor. and the inertia force. Also, the limitation of a passive isolation is presented. To simplify the dynamic analysis and to establish a proper design method for supporting system, each of the machine and the floor is modeled as a single degree of freedom spring-mass-damper system under careful investigation of the dynamic characteristics of each system and appropriate assumptions. Then, the dynamic behavior of a 2DOF system and the effect of the mass and the damping are investigated. Also, the characteristics of motion profiles are investigated. In addition, a quasi-static analysis on the transmitted force through support is performed and related tests are performed.

• Tribology and Lubricants
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• v.20 no.2
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• pp.58-67
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• 2004

In this study a general Galerkin FE lubrication analysis method for the compressible Reynolds equation in cylindrical coordinates is presented. Then, the method is applied for analyzing lubrication performances of spiral groove dry gas seals. The effects of toning and number of groove on performance indices are evaluated at low and high rotating speeds: 3,600 and 15,000 rpm. Results show that, for the primary design consideration performances such as the opening force and axial and angular stiffnesses, a negative or small coning and a large number of groove are preferred.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.1
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• pp.86-91
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• 2007

A sensor using quartz toning fork is presented for measuring liquid density. It consists of a PZT plate as an actuator for piezoelectric excitation and a quartz tuning fork as a sensor for resonant frequency detection. The resonant frequency is determined from the sensing voltage measured in tuning fork when the excitation frequencies of PZT actuator are swept around the resonant frequencies of tuning fork. The resonant frequency determined the liquid density. The density values of three kinds of organic solvents are measured and compared with the standard values. The experimental results are in agreement with the standard values and the maximum standard deviation is less than 9%.