• Journal of Environmental Health Sciences
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• v.27 no.2
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• pp.43-50
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• 2001

This paper reviews the results of a series of efforts to develop structure-activity models for slow-reacting chemicals and olefins whose toxicity may be enhanced by the ultraviolet radiation. Photoinduced toxicity of 14 compounds was found to be a different result of competing factors of structure, having carbon-carbon double bonds. To mimic the biological consequences of photooxidative damage in mammalian cells, the photochemical mutagenicith of 14 chemicals was tested in the CAS. Simple olefins were photochemically mutagenic or carcinogenic with irradiation, increasing the alkylating activity from zero level to 0.87(abs/gram) for styrene, 0.25 for 1-butene, 0.11 for 1-hexene, respectively, whereas no photochemical mutagenicity was observed with 1-octene in the absence of the CAS. Oxide compounds, however, showed a decreasing trend of photoalkylating activities in the presence or absence of the CAS. We found that the structure-activity relationship was not applicable to our data.

• Journal of the Korean Ceramic Society
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• v.48 no.5
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• pp.390-395
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• 2011

The objective of our study was to produce an imitation bone material consisting of hydroxyapatite with a compact and spongy structure. This study shows the ideal content of $SiO_2$ and the sintering temperature to produce imitation bone that has the mechanical properties of natural bone. On the basis of our determination of the ideal conditions, a compact part was produced and its mechanical properties were tested. A compact part made of 0.5 wt% $SiO_2$ and sintered at $1350^{\circ}C$ showed excellent mechanical properties. The bioactivity of the compact part under this condition was tested, and it was found to be bioactive. The porous part was produced by controlling the powder size, and the dual structure was manufactured by combining the compact and porous parts. A water permeability test confirmed that the dual structure had an interconnected pore structure. Therefore, this dual-body structure is feasible for use in the creation of implants.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.1
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• pp.47.2-47.2
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• 2011

Gravitational waves from the pulsar glitch can be detected by next generation gravitational wave observatories. We investigate characteristics of the modes that can emit the gravitational waves excited by three different types of perturbations satisfying conservation of total rest mass and angular momentum. These perturbations mimic the pulsar glitch theories i.e., change of moment of inertia due to the star quakes or angular momentum transfer by vortex unpinning at crust-core interface. We carry out numerical hydrodynamic simulations using the pseudo-Newtonian method which makes weak field approximation for the dynamics, but taking all forms of energies into account to compute the Newtonian potential. Unlike other works, we found that the first and second strongest modes that give gravitational waves are $^2p_1$ and $H_1$ rather than$^2f$. We also found that vortex unpinning model excites the inertial mode in quadrupole moment quite effectively. The inertial mode may evolve into the non-axisymmetric r-mode.

• The KIPS Transactions:PartA
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• v.17A no.2
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• pp.53-62
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• 2010

Mobile Sensor Vehicles, nodes of Mobile Sensor Network, are navigating for a specific, maybe unknown, region. For the precise usage of MSN, MSV has to be able to do localization by integrating information through communication by each other. In addition, MSV should be localized with various sensors equipped. In this research, we propose a set of techniques that improve accuracy using human mimic by combining and exploiting the existing techniques such as Dead-Reckoning, Computer Vision and Received Signal Strength Identification.

• Clinics in Shoulder and Elbow
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• v.17 no.2
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• pp.80-83
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• 2014

A 29-year-old man visited our clinic owing to a persistent swelling in the anterior part of the left elbow joint that began one year ago. Through magnetic resonance imaging (MRI), we observed tenosynovitis with multiple rice bodies, and so we performed an excisional biopsy and tenosynovectomy. Through pathology and culture tests, we identified tuberculosis in the tissue biopsy that we harvested intraoperatively. Following the anti-tuberculosis medication relieved the patient's symptoms without recurrence. Since tuberculosis of the elbow occurs only rarely, and the symptoms mimic those of rheumatoid synovitis or of non-specific chronic synovitis, early diagnosis and appropriate treatment are often delayed. The authors report this rare case of tuberculous tenosynovitis of the elbow with a review of the relevant literature.

• The Korean Journal of Cytopathology
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• v.19 no.2
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• pp.200-205
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• 2008

Hibernoma is a rare, benign adipose tumor composed of brown fat cells with eosinophilic granular or multivacuolated cytoplasm. The cytologic features of hibernoma have been rarely reported and may mimic other polygonal cell neoplasms. We report the imprint cytologic features of a case of hibernoma in the left thigh of a 68-year-old woman. Microscopic examination showed large, round, or polygonal brown fat cells. The cells were arranged in fragments or clusters. The nuclei were uniformly round with finely granular chrornatin. The cytoplasm was multivacuolated or univacuolated. The abundant eosinophilic granular cytoplasm was also present. No nuclear atypia were present. Immunohistochemical staining showed that cells were positive for S-100 protein.

• International Journal of Aeronautical and Space Sciences
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• v.13 no.1
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• pp.1-13
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• 2012

Over 3.8 billion years, through evolution nature came up with many effective continually improving solutions to its challenges. Humans have always been inspired by nature capabilities in problems solving and innovation. These efforts have been intensified in recent years where systematic studies are being made towards better understanding and applying more sophisticated capabilities in this field that is increasingly being titled biomimetics. The ultimate challenge to this field is the development of humanlike robots that talk, interpret speech, walk, as well as make eye-contact and facial expressions with some capabilities that are exceeding the original model from nature. This includes flight where there is no creature that is as large, can fly as high, carry so heavy weight, fly so fast, and able to operate in extreme conditions as the aircraft and other aerospace systems. However, there are many capabilities of biological systems that are not feasible to mimic using the available technology. In this paper, the state-of-the-art of some of the developed biomimetic capabilities, potentials and challenges will be reviewed.

• Journal of Biomedical Engineering Research
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• v.32 no.2
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• pp.118-126
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• 2011

This study proposes a human body orientation tracking system by inertial and earth magnetic sensors. These sensors were fused by indirect Kalman filter. The proposed tracking system was configured and the filter was implemented. The tracking performance was evaluated with static and dynamic tests. In static test, the sensor was fixed on the floor while its static characteristics was analyzed. In dynamic test, the sensor was held and moved manually for 30 seconds. The dynamic test included x, y, z axis rotations, and elbow flection/extension motions that mimic drinking. For these dynamic motions, the tracking angle error was under $4.1^{\circ}$ on average. The proposed tracking method is expected to be useful for various human body motion analysis.

• 한국가시화정보학회:학술대회논문집
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• 2006.12a
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• pp.117-120
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• 2006

Inspiring or mimicking biological bodies is regarded as one of a breakthrough in the conventional engineering. The bird's motion is one of the mimicking objects. Seagulls fly under strong storm at sea. An attempt of investigating into the characteristics of a seagull model's motion and its flow fields has been made in this study. Three cameras, two for motion capture and one for flow field, were used. The motions of the seagull's wing have been reconstructed, and the flow characteristics around the wing have been investigated with 2D-PIV measurements.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.12
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• pp.3296-3314
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• 2012

We present a novel approach for the simulation of color pencil effects using line integral convolution (LIC) to produce pencil drawings from images. Our key idea is to use a bilateral convolution filter to simulate the various effects of pencil strokes. Our filter resolves the drawbacks of the existing convolution-based schemes, and presents an intuitive control to mimic the properties of pencil strokes. We also present a scheme that determines stroke directions from the shapes to be drawn. Smooth tangent flows are used for the pixels close to feature lines, and partially parallel flows inside regions. The background is rendered using a flow of fixed direction. Using different styles of stroke directions increases the realism of the resulting images. This approach produces convincing pencil drawing effects from photographs.