• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.902-905
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• 2008

With development of internet, location-based service (LBS) is getting more interest in wire and wireless network, and many studies are in progress to provide various services such as GIS and GPS technique related to this. Today positioning and information providing service is accomplished by mobile communication companies' chasing the cell or building unique GIS system, but there is a lot of building-cost that must be endured to define boundary of collecting precise location information from chasing Cell and provide unique location information service. In this paper, it desires to make the database of location information with using GPS, relatively precise satellite positioning system, to cut the cost of building location information service, and to present service models such as children's positioning service that is to reduce the cost of building GIS by using Web Open API and provide location information of discrete object in real-time.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.496-501
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• 1995

Experiments were carried out to find out the optimal condition of SCP produced by Cellulomonas sp. KL-6 and to evaluate nutritional value for the protein of this organism Intracellular- and extracellular proteins produced by this strain were estimated to be nearly maximum, $266\;{\mu}g/m{\ell}\;and\;37\;{\mu}g/m{\ell}$, in the medium containing 0.001% of thiamin after 5 days cultivation. When used rice straw as carbon source for the cell growth of this organism after crusing them by cutting mill, and treating them with 1.0% of NaOH and 10.0% of $NH_4OH\;at\;80^{\circ}C$ for 30 minutes and neutralizing continuatively them with 85% of $H_3PO_4$, SCP production rates were very increased to $1.63\;g/{\ell}$ (NaOH) and $1.47\;g/{\ell}$ (NH4OH), respectively than $0.5\;g/{\ell}$ produced in untreated rice straw. We compared their amino acids patterns with that of FAO provisional patterns. Amino acids content of strain KL-6 was excellents. However. when intended these cell mass to use in practical animal feeding test it would be advisable that destruction or lysis of cell wall should be done.

• Transactions of Materials Processing
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• v.20 no.3
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• pp.193-205
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• 2011

Because of its rustproof property, stainless steel is widely used in kitchen appliances, building materials, electronics, chemical plants and automobile exhausts. In addition, the utilization of stainless steel for fuel cell application is growing. As the demand for this material increases, it is necessary to study the basic properties of stainless steel such as corrosion resistance, heat transfer, formability, cutting or shearing ability and weldability. In this article, the mechanical properties, formability and press forming performance of stainless steel are reviewed. Since temperature and strain rate affect the press forming performance of STS304(austenitic) stainless steel, the influence of these parameters on the plastic behavior should be investigated. Moreover, measures for the prevention of ridging of STS430(ferritic) and delayed fracture of STS430, which respectively appear during and after press forming, should be considered. Recently, stainless steel sheets with a thickness lower than 0.2 mm have been widely used in applications for mobile phone, digital camera and fuel cell separator. Therefore, there is a growing interest of studying the grain size effect and plasticity at the crystal scale in order to understand the anisotropic behavior and micro forming ability of thin sheets. This review paper was written with the objective of helping engineers and researchers to understand the forming characteristics of stainless steel and to establish standards in plastic forming techniques.

• Journal of Animal Science and Technology
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• v.59 no.11
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• pp.24.1-24.14
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• 2017

Over the past decades, in vitro culture media have been developed to successfully support IVF embryo growth in a variety of species. Advanced reproductive technologies, such as somatic cell nuclear transfer (SCNT), challenge us with a new type of embryo, with special nutritional requirements and altered physiology under in vitro conditions. Numerous studies have successfully reconstructed cloned embryos of domestic animals for biomedical research and livestock production. However, studies evaluating suitable culture conditions for SCNT embryos in wildlife species are scarce (for both intra- and interspecies SCNT). Most of the existing studies derive from previous IVF work done in conventional domestic species. Extrapolation to non-domestic species presents significant challenges since we lack information on reproductive processes and embryo development in most wildlife species. Given the challenges in adapting culture media and conditions from IVF to SCNT embryos, developmental competence of SCNT embryos remains low. This review summarizes research efforts to tailor culture media to SCNT embryos and explore the different outcomes in diverse species. It will also consider how these culture media protocols have been extrapolated to wildlife species, most particularly using SCNT as a cutting-edge technical resource to assist in the preservation of endangered species.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.6
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• pp.525-528
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• 2011

A deep circumflex iliac artery (DCIA) flap is usually used for reconstruction in oral and maxillo-facial surgery department since introduced by O'Brien in 1975. Various flap designs are possible for osteomusculocutaneous, musculocutaneous, musculosseous and vascularized bone types. Iliac crest shape is similar to contour of mandible. Moreover, though a fibular flap has only 15~20 mm of cutting plane width, a DCIA flap contains much more bone amount, making this a similar reconstruction compare with normal mandible. A 68 year-old male with squamous cell carcinoma on the anterior floor of the mouth had an impression with T2N0Mx and the treatment procedure was DCIA reconstruction after wide resection and marginal mandibulectomy, with both supraomohyoid neck dissection. We present an experience of DCIA flap for reconstruction with a literature review.

• BMB Reports
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• v.43 no.6
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• pp.383-388
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• 2010

The number of cancer patients has increased due to longer life spans and treatment has become a universal problem. Since molecular-targeted therapies were introduced as a new developmental strategy, certain targets have been examined hundreds of times, with developers overlapping their research efforts. We need to focus our energy and resources on novel drug candidate identification and optimization, in order to enhance the entry of early-stage drug candidates into the therapeutics pipeline. This presents a major opportunity for Korea to jump the decades-old development gap between our programs and those that are more advanced in other countries. Although this country does not have a specific center for validation and development of cancer therapeutics, we do have cutting-edge scientists performing research in many institutions. In this paper, I will review cancer drug development in Korea and suggest future directions, while urging colleagues to utilize their networking expertise so we can move toward a new paradigm of novel therapeutics development. An example of such efforts has begun with the Drug Development Consortium, which was described in the KSBMB chapter. This consortium was launched in 2010 by biochemists, chemists, cell and molecular biologists and pharmacologists. It is clear that effective cancer therapeutics will be developed more efficiently when we all strive for the same goal.

• International Journal of Oral Biology
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• v.32 no.1
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• pp.13-22
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• 2007

The stem cell research is emerging as a cutting edge topic for a new treatment for many chronic diseases. Recently, dental stem cell would be possible for regeneration of tooth itself as well as periodontal tissue. However, the study of the cell characterization is scarce. Therefore, we performed the genetic profiling and the characterization of mouse fetus/neonate derived dental tissue and cell to find the identification during dental development. We separated dental arch from mandibles of 14.5 d fetal mice and neonate 0 d under the stereoscope, and isolated dental cells primarily from the tissues. Then, we examined morphology and the gene expression profiles of the primary cells and dental tissues from fetus/neonate and adult with RT-PCR. Primary dental cells showed heterogeneous but the majority was shown as fibroblast-like morphology. The change of population doubling time levels (PDLs) showed that the primary dental cells have growth potential and could be expanded under our culture conditions without reduction of growth rate. Immunocytochemical and flow cytometric analyses were performed to characterize the primary dental cell populations from both of fetus (E14.5) and neonate. Alpha smooth muscle actin (${\alpha}-SMA$), vimentin, and von Willebrand factor showed strong expression, but desmin positive cells were not detected in the primary dental cells. Most of the markers were not uniformly expressed, but found in subsets of cells, indicating that the primary dental cell population is heterogeneous, and characteristics of the populations were changed during culture period. And mesenchymal stem cell markers were highly expressed. Gene expression profile showed Wnt family and its related signaling molecules, growth factors, transcription factors and tooth specific molecules were expressed both fetal and neonatal tissue. The tooth specific genes (enamelin, amelogenin, and DSPP) only expressed in neonate and adult stage. These expression patterns appeared same as primary fetal and neonatal cells. In this study we isolated primary cells from whole mandible of fetal and neonatal mice. And we investigated the characteristics of the primary cells and the profile of gene expressions, which are involved in epithelial-mesenchymal interactions during tooth development. Taken together, the primary dental cells in early passages or fetal and neonatal mandibles could be useful stem cell resources.

• ETRI Journal
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• v.35 no.1
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• pp.158-161
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• 2013

This letter proposes a low-power current-steering digital-to-analog converter (DAC). The proposed DAC reduces the clock power by cutting the clock signal to the current-source cells in which the data will not be changed. The 10-bit DAC is implemented using a $0.13-{\mu}m$ CMOS process with $V_{DD}$=1.2 V. Its area is $0.21\;mm^2$. It consumes 4.46 mW at a 1-MHz signal frequency and 200-MHz sampling rate. The clock power is reduced to 30.9% and 36.2% of a conventional DAC at 1.25-MHz and 10-MHz signal frequencies, respectively. The measured spurious free dynamic ranges are 72.8 dB and 56.1 dB at 1-MHz and 50-MHz signal frequencies, respectively.

• Journal of computational fluids engineering
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• v.4 no.3
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• pp.52-62
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• 1999

The development of a parallelized aerodynamic simulation process involving moving bodies is presented. The implementation of this process is demonstrated using a fully systemized Chimera methodology for steady and unsteady problems. This methodology consists of a Chimera hole-cutting, a new cut-paste algorithm for optimal mesh interface generation and a two-step search method for donor cell identification. It is fully automated and requires minimal user input. All procedures of the Chimera technique are parallelized on the Cray T3E using the MPI library. Two and three-dimensional examples are chosen to demonstrate the effectiveness and parallel performance of this procedure.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1469-1474
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• 2007

In recent years, research to machine large-surface micro-features has become important because of the light guide panel of a large-scale liquid crystal display and the bipolar plate of a high-capacity proton exchange membrane fuel cell. In this study, in order to realize the systematic design technology and performance improvements of an ultra-precision machine for machining the large-surface micro-features, a structural characteristic analysis was performed using its virtual prototype. The prototype consisted of gantry-type frame, hydrostatic feed mechanisms, linear motors, brushless DC servo motor, counterbalance mechanism, and so on. The loop stiffness was estimated from the relative displacement between the tool post and C-axis table, which was caused by a cutting force. Especially, the causes of structural stiffness deterioration were identified through the structural deformation analysis of sub-models.