• Korean Journal of Metals and Materials
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• v.49 no.11
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• pp.910-915
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• 2011

The microstructures and mechanical properties of roll-bonded STS439/Al1050/STS304 clad materials were investigated after an annealing process at various temperatures. Interfacial layer was developed at the STS439/Al1050 and Al1050/STS304 interfaces at $550^{\circ}C$. STS439/Al1050/STS304 clad metals fractured suddenly in a single step and the fracture decreased with increasing annealing temperatures at $450^{\circ}C$. After annealing at $550^{\circ}C$, samples fractured in three steps with each layer fracturing independently. Interfacial layers formed at $550^{\circ}C$ with a high Vickers microhardness were found to be brittle. During tensile testing, periodic parallel cracks were observed at the interfacial reaction layer. Observed micro-void between Al1050 and the interfacial layer was found to weaken the Al1050/reaction layer interface, leading to the total separation between Al1050 and the reaction layer.

• Archives of Plastic Surgery
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• v.48 no.2
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• pp.179-184
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• 2021

Women attach great importance to the presence of a three-dimensional nipple upon completion of the breast reconstruction process. To meet patients' expectations, nipple-areolar complex reconstruction should achieve symmetry in position, size, shape, texture, and color, as well as minimizing donor-site morbidity. However, it is well known that regardless of the reconstructive technique, loss of nipple projection can be reasonably expected. We developed and evaluated a quick, simple, and innovative technique using injectable Integra Flowable Wound Matrix to increase nipple projection after reconstruction. Twenty breast cancer patients who underwent nipple reconstruction resulting in unsatisfactory projection were enrolled in our retrospective study. Nipple projection was measured at the time of surgery and after 6 and 12 months. A visual analogue scale was used to assess patients' satisfaction. Our technique yielded reliable results in terms of the long-lasting maintenance of nipple projection. This method is high-priced, but cost-effective, since one kit may suffice for three patients. Furthermore, our patients were very appreciative of this technique as a single-step, minimally invasive, painless procedure with no reported necessity of re-intervention.

• Advances in nano research
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• v.11 no.6
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• pp.657-665
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• 2021

The present work aimed to explore green approach via aqueous leaves extract of Murraya koenigii (ALEMk) for the synthesis of silver nanoparticles (AgNPsMk) in single step. The synthesis process was visualized with a color change and monitored by employing UV/Visible spectroscopy and a clear peak attained at 420 nm confirming the synthesis of AgNPsMk. The possible functional groups present in the extract which participated in the synthesis of AgNPsMk were identified with the help of FTIR spectroscopy. Further characterization using TEM images revealed the spherical shape of AgNPsMk with average particle size of 20 nm displaying well dispersion throughout the solution. Pronounced antioxidant activities of AgNPsMk at increased concentrations observed which evidencing strong radical scavenging ability. Moreover, AgNPsMk exhibited strong antibacterial behavior when tested against bacterial strains of Escherichia coli and Bacillus subtilis. Moving ahead, in vitro cytotoxicity work revealed potent cell viability loss appearing in AU565 and HeLa cancer cell lines on exposure to AgNPsMk at increased concentration. Finally, in vivo assessment carried out inside male Wistar rats indicated non toxic effect on examined liver tissues besides biochemical analysis including bilirubin, alkaline phosphtase (ALP) and serum glutamate pyruvate transaminase (SGPT) which found within the normal range when compared with control. The prior research work profoundly apprises the potential of green synthesized AgNPsMk to play a significant role in biomedical applications and formulations.

• Journal of Multimedia Information System
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• v.8 no.4
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• pp.259-266
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• 2021

Security vulnerabilities have been reported in major design software systems such as Adobe Photoshop and Illustrator, which are recognized as de facto standard design tools in most of the design industries. Companies need to evaluate and manage their risk levels posed by those vulnerabilities, so that they could mitigate the potential security bridges in advance. In general, security vulnerabilities are discovered throughout their life cycles repeatedly if software systems are continually used. Hence, in this study, we empirically analyze risk levels for the three major graphical design software systems, namely Photoshop, Illustrator and GIMP with respect to a software vulnerability discovery model. The analysis reveals that the Alhazmi-Malaiya Logistic model tends to describe the vulnerability discovery patterns significantly. This indicates that the vulnerability discovery model makes it possible to predict vulnerability discovery in advance for the software systems. Also, we found that none of the examined vulnerabilities requires even a single authentication step for successful attacks, which suggests that adding an authentication process in software systems dramatically reduce the probability of exploitations. The analysis also discloses that, for all the three software systems, the predictions with evenly distributed and daily based datasets perform better than the estimations with the datasets of vulnerability reporting dates only. The observed outcome from the analysis allows software development managers to prepare proactively for a hostile environment by deploying necessary resources before the expected time of vulnerability discovery. In addition, it can periodically remind designers who use the software systems to be aware of security risk, related to their digital work environments.

• Korean Chemical Engineering Research
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• v.61 no.2
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• pp.273-277
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• 2023

The biosorption of methylene blue (MB) from aqueous solution was investigated using dried Rhodotorula glutinis as the biosorbent. The effects of pH, initial dye concentration, biosorbent dosage, and kinetic studies were determined to obtain valuable information for biosorption. Results indicated that most of the adsorbed MB bound within 30 minutes of contact and the MB adsorption capacity increased from 21.1 to 101.8 mg/g with the initial MB concentration increased from 50 to 300 mg/L. Additionally, the MB adsorption capacity gradually increased from pH 4.0 to 9.0, reaching its peak at an initial pH of 9.0. As the biomass load was increased from 0.25 to 4.0 g/L, the MB removal efficiency increased from 14.1 to 84.5%. The Langmuir model provided the best fit throughout the concentration range, and the maximum adsorption capacity (q_max) and Langmuir constant (b) were determined to be 135.14 mg/g and 0.026 l/mg, respectively. Furthermore, the biosorbent process of R. glutinis was found to follow pseudo-second-order kinetics and the calculated q_eq,cal value showed good agreement with the experimental q_eq value. Overall, the biosorption of MB by R. glutinis can be characterized as a monolayer, single site type phenomenon, and the rate-limiting step was determined to be the chemical reaction between the adsorbent and the adsorbate.

• Design & Manufacturing
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• v.16 no.2
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• pp.53-59
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• 2022

Unlike other press forming processes, ISF (Incremental sheet forming) doesn't require a punch and die set. However, during the ISF processes unwanted bending deformation occurred around the target geometry. This paper is aimed to analyze the effect of the die structure, which is supported by bolts, on the geometric accuracy of the ISF processes. In this research, the ISF processes with Al5052 sheet of 0.5 mm, the tool diameter of 6 mm and the stepdown of 0.4 mm was employed. L-shaped, step-shaped, relief-shaped geometry were employed in experiments. Sectional view and the plastic strain were compared. From this research we find out that the bolt supported ISF processes increases the geometric accuracy of products very effectively.

• Korean Journal of Optics and Photonics
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• v.8 no.4
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• pp.327-332
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• 1997

We fabricated the high speed 1.55${\mu}{\textrm}{m}$ distributed feedback laser diodes (DFB-LD) using both two-step mesa etching process and semi-insulating InP current blocking layers. The devices characteristics were threshold current of ~15mA, slope efficiency of ~0.13mW/mA, and dynamic resistance of ~6.0Ω, with as-cleaved facets. The fabricated DFB-LD showed the single longitudinal mode with more than 40dB up to 6 $I_{th}$(CW condition), emitting at the wavelength of 0.546${\mu}{\textrm}{m}$. The -3dB bandwidth was >10㎓ at the driving current of 27mA, and the maximum -3dB bandwidth was ~18㎓ at 90 mA current, showing the superior frequency response of SI-PBH DFB-LD. In the 10Gb/s transmission experiment for 1.55${\mu}{\textrm}{m}$ DFB-LD module, maximum 10 km of single mode fiber(SMF) or 80 km of dispersion shifted fiber (DSF) could be transmitted with error free.

• Journal of Korea Multimedia Society
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• v.9 no.4
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• pp.421-433
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• 2006

This paper proposes a method to insert virtual objects into a real video stream based on feature tracking and camera pose estimation from a set of single-camera video frames. To insert or modify 3D shapes to target video frames, the transformation from the 3D objects to the projection of the objects onto the video frames should be revealed. It is shown that, without a camera calibration process, the 3D reconstruction is possible using multiple images from a single camera under the fixed internal camera parameters. The proposed approach is based on the simplification of the camera matrix of intrinsic parameters and the use of projective geometry. The method is particularly useful for augmented reality applications to insert or modify models to a real video stream. The proposed method is based on a linear parameter estimation approach for the auto-calibration step and it enhances the stability and reduces the execution time. Several experimental results are presented on real-world video streams, demonstrating the usefulness of our method for the augmented reality applications.

• ETRI Journal
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• v.37 no.6
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• pp.1143-1153
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• 2015

In this paper, we propose an efficient architecture for a real-time image stitching engine for vision SoCs found in motor vehicles. To enlarge the obstacle-detection distance and area for safety, we adopt panoramic images from multiple telegraphic cameras. We propose a stitching method based on a fixed homography that is educed from the initial frame of a video sequence and is used to warp all input images without regeneration. Because the fixed homography is generated only once at the initial state, we can calculate it using SW to reduce HW costs. The proposed warping HW engine is based on a linear transform of the pixel positions of warped images and can reduce the computational complexity by 90% or more as compared to a conventional method. A dual-core SW/HW image stitching engine is applied to stitching input frames in parallel to improve the performance by 70% or more as compared to a single-core engine operation. In addition, a dual-core structure is used to detect a failure in state machines using rock-step logic to satisfy the ISO26262 standard. The dual-core SW/HW image stitching engine is fabricated in SoC with 254,968 gate counts using Global Foundry's 65 nm CMOS process. The single-core engine can make panoramic images from three YCbCr 4:2:0 formatted VGA images at 44 frames per second and frequency of 200 MHz without an LCD display.

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.262-270
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• 2007

Of the twelve lytic bacteriophages recovered from five different fermenting cucumber tanks that were inoculated with Pediococcus sp. LA0281, a lytic phage, ${\phi}ps05$, was characterized in the present study. The plaques were mostly clear and round-shaped on the lawn of starter strain, indicating lytic phage. Overall appearance indicated that it belongs to the Siphoviridae family or Bradley's group B1, with a small isometric head and a flexible noncontractile tail with swollen base plate. The average size was found to be 51.2 nm in head diameter and 11.6 nm wide ${\times}$ 129.6 nm long for the tail. The single-step growth kinetics curve showed that the eclipse and the latent period were 29 min and 34 min, respectively, and an average burst size was calculated to be 12 particles per infective center. The optimum proliferating temperature ($35^{\circ}C$) was slightly lower than that of cell growth ($35\;to\;40^{\circ}C$). The structural proteins revealed by SDS-PAGE consisted of one main protein of 33 kDa and three minor proteins of 85, 58, and 52 kDa. The phage genome was a linear double-stranded DNA without cohesive ends. Based on the single and double digestion patterns obtained by EcoRI, HindIII, and SalI, the physical map was constructed. The overall size of the phage genome was estimated to be 24.1 kb. The present report describes the presence of a lytic phage active against a commercial starter culture Pediococcus sp. LA0281 in cucumber fermentation, and a preliminary study characterizes the phage on bacterial successions in the process of starter-added cucumber fermentation.