• Korean Journal of Microbiology
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• v.37 no.4
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• pp.245-252
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• 2001

Erm proteins, MLS (macrolide-lincosamide-streptogramin B) resistance factor proteins, show high degree of amino acid sequence homology and comprise of a group of structurally homologous N-methyltransferases. On the basis of the recently determined structures of ErmC` and ErmAM, ErmSF was divided into two domains, N-terminal end catalytic domain and C-terminal end substrate binding domain and attempted to overexpress catalytic domain in E. coli using various pET expression systems. Three DNA fragments were used to express the catalytic domain: DNA fragment 1 encoding Met 1 through Glu 186, DNA fragment 2 encoding Arg 60 to Glu 186 and DNA fragment 3 encoding Arg 60 through Arg 240. Among the pET expression vectors used, pET 19b successfully expressed the DNA fragment 3 and pET23b succeeded in expression of DNA fragment 1 and 2. But the overexpressed catalytic domains existed as inclusion body, a insoluble aggregate. To assist the soluble expression of ErmSF catalytic domains, Coexpression of chaperone GroESL or Thioredoxin and lowering the incubation temperature to $22^{\circ}C$ were attempted, as did in the soluble expression of the whole ErmSF protein. Both strategies did not seem to be helpful. Solubilization with guanidine-HCl and renaturation with gradual removal of denaturant and partial digestion of overexpressed whole ErmSF protein (expressed to the level of 126 mg/ι culture as a soluble protein) with proteinase K, nonspecific proteinase are under way.

• Economic and Environmental Geology
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• v.21 no.2
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• pp.149-164
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• 1988

Electrum-sulfide mineralization of the Samgwang and Sobo mines of the Cheongyang Au-Ag area was deposited in two stages of quartz and calcite veins that fill fault zones in granite gneiss. Radiometric dating indicates that mineralization is Early Cretaceous age (127 Ma). Fluid inclusion and sulfur isotope data show that ore mineralization was deposited at temperatures between $340^{\circ}$ and $180^{\circ}C$ from fluids with salinities of 1 to 8 wt. % equiv. NaCl and a ${\delta}^{34}S_{{\sum}S}$ value of 2 to 5 per mil. Evidence of fluid boiling (and $CO_2$ effervescence) indicates a range of pressures from < 200 to $\approx$ 700 bars, corresponding to depths of ${\approx}1.5{\pm}0.3\;km$ in a hydrothermal system which alternated from lithostatic toward hydrostatic conditions. Au-Ag deposition was likely a result of boiling coupled with cooling. Meaured and calculated hydrogen and oxygen isotope values of ore-forming fluids indicate a significant meteoric water component, approaching unexchanged paleometeoric water values. Comparison of these values with those of other Korean Au-Ag deposits reveals a relationship among depth, Au/Ag ratio and degree of water-rock interaction. All investigated Korean Jurassic and Cretaceous gold-silver-bearing deposits have fluids which are dominantly evolved meteoric waters, but only deeper systems (${\geq}1.5\;km$) are exclusively gold-rich.

• Journal of Intelligence and Information Systems
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• v.24 no.2
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• pp.171-193
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• 2018

LOD(Linked Open Data) cloud is a practical implementation of semantic web. We suggested a new method that provides identity links conveniently in LOD cloud. It also allows changes in LOD to be reflected to searching results without any omissions. LOD provides detail descriptions of entities to public in RDF triple form. RDF triple is composed of subject, predicates, and objects and presents detail description for an entity. Links in LOD cloud, named identity links, are realized by asserting entities of different RDF triples to be identical. Currently, the identity link is provided with creating a link triple explicitly in which associates its subject and object with source and target entities. Link triples are appended to LOD. With identity links, a knowledge achieves from an LOD can be expanded with different knowledge from different LODs. The goal of LOD cloud is providing opportunity of knowledge expansion to users. Appending link triples to LOD, however, has serious difficulties in discovering identity links between entities one by one notwithstanding the enormous scale of LOD. Newly added entities cannot be reflected to searching results until identity links heading for them are serialized and published to LOD cloud. Instead of creating enormous identity links, we propose LOD to prepare its own link policy. The link policy specifies a set of target LODs to link and constraints necessary to discover identity links to entities on target LODs. On searching, it becomes possible to access newly added entities and reflect them to searching results without any omissions by referencing the link policies. Link policy specifies a set of predicate pairs for discovering identity between associated entities in source and target LODs. For the link policy specification, we have suggested a set of vocabularies that conform to RDFS and OWL. Identity between entities is evaluated in accordance with a similarity of the source and the target entities' objects which have been associated with the predicates' pair in the link policy. We implemented a system "Change Acceptable In-Depth Searching System(CAIDS)". With CAIDS, user's searching request starts from depth_0 LOD, i.e. surface searching. Referencing the link policies of LODs, CAIDS proceeds in-depth searching, next LODs of next depths. To supplement identity links derived from the link policies, CAIDS uses explicit link triples as well. Following the identity links, CAIDS's in-depth searching progresses. Content of an entity obtained from depth_0 LOD expands with the contents of entities of other LODs which have been discovered to be identical to depth_0 LOD entity. Expanding content of depth_0 LOD entity without user's cognition of such other LODs is the implementation of knowledge expansion. It is the goal of LOD cloud. The more identity links in LOD cloud, the wider content expansions in LOD cloud. We have suggested a new way to create identity links abundantly and supply them to LOD cloud. Experiments on CAIDS performed against DBpedia LODs of Korea, France, Italy, Spain, and Portugal. They present that CAIDS provides appropriate expansion ratio and inclusion ratio as long as degree of similarity between source and target objects is 0.8 ~ 0.9. Expansion ratio, for each depth, depicts the ratio of the entities discovered at the depth to the entities of depth_0 LOD. For each depth, inclusion ratio illustrates the ratio of the entities discovered only with explicit links to the entities discovered only with link policies. In cases of similarity degrees with under 0.8, expansion becomes excessive and thus contents become distorted. Similarity degree of 0.8 ~ 0.9 provides appropriate amount of RDF triples searched as well. Experiments have evaluated confidence degree of contents which have been expanded in accordance with in-depth searching. Confidence degree of content is directly coupled with identity ratio of an entity, which means the degree of identity to the entity of depth_0 LOD. Identity ratio of an entity is obtained by multiplying source LOD's confidence and source entity's identity ratio. By tracing the identity links in advance, LOD's confidence is evaluated in accordance with the amount of identity links incoming to the entities in the LOD. While evaluating the identity ratio, concept of identity agreement, which means that multiple identity links head to a common entity, has been considered. With the identity agreement concept, experimental results present that identity ratio decreases as depth deepens, but rebounds as the depth deepens more. For each entity, as the number of identity links increases, identity ratio rebounds early and reaches at 1 finally. We found out that more than 8 identity links for each entity would lead users to give their confidence to the contents expanded. Link policy based in-depth searching method, we proposed, is expected to contribute to abundant identity links provisions to LOD cloud.

• Economic and Environmental Geology
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• v.28 no.6
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• pp.541-551
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• 1995

The Yeongdeog gold-silver deposits at Jipum, Gyeongsangbugdo, is of a middle Paleogene $(45.52{\pm}1.02Ma)$ vein type, and is hosted in shale and sandstone of Cretaceous age. Based on mineral paragenesis, vein structure and mineral assemblages, the ore mineralization can be divided into two distinct depositional stages. The early stage is associated with base-metals such as pyrite, arsenopyrite (27.99~30.99 at%), hematite, rutile, pyrrhotite, sphalerite (10.53~18.42 FeS mole%), chalcopyrite and galena with wallrock alteration such as chlorite, sericite and pyrite. The late stage is characterized by the Au-Ag mineralization such as electrum, Ag-bearing tetrahedrite, freibergite, pyrargyrite, unidentified mineral, pyrite, sphalerite (1.08~5.57 FeS mole%), chalcopyrite and galena. Fluid inclusion data indicate that fluid temperatures and salinities range from 343 to $227^{\circ}C$ and from 8.3 to 5.7 wt% eq. NaCl in early stage, respectively. Temperatures and salinities of NaCl eq. wt% range from 299 to $225^{\circ}C$ and from 12.9 to 4.3 in late stage, respectively. They suggest that complex cooling histories were occured by the mixing of the fluids. Sulfur fugacity $(-logfs_2)$ deduced by mineral assemblages and composition ranges from 8.3 to 14.7 atm. in early stage, and from 8.8 to 14.5 atm. in late stage. It suggests that the mineralization was related to decrease of temperature in early stage and fluctuations of $fS_2$ with decrease of temperature in late stage. Sulfur and oxygen isotope compositions are 4.48~5.60‰ and 9.25~10.8% in early stage, and late stage is 4.84~7.00‰ and 5.7‰, respectively. It indicated that hydrothermal fluids may be magmatic origin with some degree of mixing of another water during paragenetic time.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.1
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• pp.131-138
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• 2006

Structural bracing concept equipped with a new and efficient friction based energy dissipation device is referred to Friction SliP Brace (FSB) where the behavior of the brace components is elastic until the axial resistant force in the brace exceeds the friction force developed at the frictional interface of the device. In this study, the FSB concept is modified and new type of hybrid energy dissipation device, the Active Friction SliP Braces (AFSB), is described. The FSB is by far improved in the AFSB by inclusion of an active clamping mechanism on the friction interface. The clamping action regulated by the developed algorithm is altered during the response of the building. The results indicate that the action of dissipating vibrational energy in the AFSB impacts on the response at later cycles by keeping the drift amplitudes at much lower levels, revealing overshooting problem due to its early slippage. Providing predetermined constant incremental strengths to the building by AFSB medium improves response by reducing drift amplitudes and base shear under small and medium amplitude ground accelerations.

• Women's Health Nursing
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• v.19 no.2
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• pp.67-74
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• 2013

Purpose: Dysmenorrhea is a menstrual condition characterized by severe and frequent cramps and pain. Effective treatment methods for dysmenorrhea are not yet fully understood. This research compares the effects of pain killers and heated red bean pillows. Methods: Data were got on demographic data, menstrual cycle status, and activities of daily living (ADLs) limitations, dysmenorrhea severity and menstrual pain scores. Following a 10% drop-out rate, 44 young women satisfied the inclusion criteria. To prevent any bias, the experimental and control groups were selected from different campuses. We used two sizes of red bean pillows: $13{\times}11.5cm$, weighing 400g; and $15{\times}18cm$, weighing 220g. For analysis, we used IBM SPSS statistics 19.0. Results: Ninety-nine point seven percentage of total subjects reported moderate to severe dysmenorrhea and 63.6% reported as moderate to severe daily activities limitations. The mean pain score with visual analogue scale was $80.2{\pm}9.42$ of 100 and 86.4% used pain killers to alleviate menstrual discomfort in all the subjects. In both groups, all three variables showed significant improvement and the Moos's Menstrual Distress Questionnaire (MDQ) scores changed significantly between menstrual and post-menstrual time point at within groups and not significantly different at premenstrual and menstrual time point at between groups. However, the MDQ score was significantly higher in experimental group than control group at post-menstruation time point and the degree of satisfaction was higher in the control group. Conclusion: This research shows that red-bean pillows on the abdomen are effective in assisting the ADL and diminishing pain severity. With regard to its safety the study indicates it can be a convenient and safe option for female students with menstrual discomfort in schoolas a non-pharmacological self-help.

• Imaging Science in Dentistry
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• v.35 no.3
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• pp.167-173
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• 2005

Purpose : To investigate the relationship between three-dimensional (3D) bone imaging parameters and trabecular strength in the mandible. Materials and Methods : Bone specimens were obtained from the mandibles of five male pigs weighing around 110 kg each. Of those, 43 samples were selected for 3D analysis and measured by micro-computed tomography. The five morphometric parameters were trabecular thickness (Tb.Th), bone specific surface (BS/BV), percent bone volume (BV/TV), structure model index (SMI) and degree of anisotropy (DA). Through destructive mechanical testing, strength parameters were obtained. Results : BV/TV, SMI, BS/BV, and Tb.Th showed significant correlations with strength parameters. DA did not show any correlation with the other parameters. In multiple linear regression analysis, BV/TV alone explained $43\%$ of the variance in Young's modulus. By stepwise inclusion of SMI, the variance in the Young's modulus was better explained up to $52\%$. Conclusions : Predicting trabecular strength in the mandible through architectural analysis would be possible. Further study is needed to establish the tendency and variety of trabecular architecture and strength according to the locations within the mandible.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.717-720
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• 2010

Purpose: Absorbable plate and screw fixation is widely used technique for internal rigid fixation in craniomaxillofacial surgery. However, there are some potential problems associated with the use of plate. The purpose of this study is to evaluate the feasibility of bone fixation in facial fracture using absorbable mesh in place of absorbable plate. Methods: The records of 55 patients with zygomaticomaxilla fractures treated by open reduction, performed by the author from February 2008 to May 2009, were retrospectively reviewed. Patients were selected to receive absorbable mesh fixation. The incidence of all complications including infection, hypoesthesia, and deformity was examined. Analysis with postoperative computed tomography follow-up demonstrates degree of reduction. Results: Forty-six patients met criteria for inclusion in the study. All patients went on to satisfactory healing without complication. Postoperative computed tomography revealed good bony alignment similarly non affected side. Conclusion: This study demonstrates that the rigid internal fixation of fractured bone fragments using absorbable mesh is more effective than absorbable plate, especially in comminuted fracture of maxilla.

• Transactions on Electrical and Electronic Materials
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• v.17 no.5
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• pp.280-288
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• 2016

Microelectronic product consumers may already be expecting another paradigm shift with smarter phones over smart phones, but the current status of microelectronic manufacturing engineering education (MMEE) in universities hardly makes up the pace for such a fast moving technology paradigm shift. The purpose of MMEE is to educate four-year university graduates to work in the microelectronics industry with up-to-date knowledge and self-motivation. In this paper, we present a comprehensive curriculum for a four-year university degree program in the area of microelectronics manufacturing. Three hands-on experienced-based courses are proposed, along with a methodology for undergraduate students to acquire hands-on experience, towards integrated circuits (ICs) design, fabrication and packaging, are presented in consideration of manufacturing engineering education. Semiconductor device and circuit design course for junior level is designed to cover how designed circuits progress to micro-fabrication by practicing full customization of the layout of digital circuits. Hands-on experienced-based semiconductor fabrication courses are composed to enhance students’ motivation to participate in self-motivated semiconductor fab activities by performing a series of collaborations. Finally, the Microelectronics Packaging course provides greater possibilities of mastered skillsets in the area of microelectronics manufacturing with the fabrication of printed circuit boards (PCBs) and board level assembly for microprocessor applications. The evaluation of the presented comprehensive curriculum was performed with a students’ survey. All the students responded with “Strongly Agree” or “Agree” for the manufacturing related courses. Through the development and application of the presented curriculum for the past six years, we are convinced that students’ confidence in obtaining their desired jobs or choosing higher degrees in the area of microelectronics manufacturing was increased. We confirmed that the hypothesis on the inclusion of handson experience-based courses for MMEE is beneficial to enhancing the motivation for learning.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.57
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• pp.243-282
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• 2013

This study aims to develop the research model about the factors that have impact on uTradeHub users' acceptance and resistance to innovation. The followings show the research hypotheses and the results of test. i) The result of H1 empirical analysis confirmed that relative advantage and task adaptedness of e-Trade have more impact on acceptance of innovation than on resistance to it. And also perceived risk and complicity of e-Trade have more impact on resistance of innovation than on acceptance to it. ii) The result of H2 analysis confirmed that the characteristics of foreign trading companies (support by CEO and IT infra maturity) has more impact on acceptance of innovation than on resistance to it. iii) The result of H3 analysis confirmed that characteristics of uTradeHub user' resistance has more impact on resistance of innovation than on acceptance to it. And also, it was confirmed that acceptance of innovation has more impact on the diffusion of e-Trade than resistance to innovation. iv) The result of H4 analysis confirmed that the difference of the degree and factors that has impact on the user's resistance and acceptance by adoption stage of e-Trade. This study has significance in that it arranges the concept and stages of e-Trade systematically and, unlike other studies, it goes beyond the acceptance and diffusion of e-Trade to the inclusion of resistance together in the model.