• Journal of Advanced Marine Engineering and Technology
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• v.28 no.1
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• pp.83-89
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• 2004

Flare nut is an important Part that used to joint a brake tube-end in automobiles. It was made of SWCH 10A by machining. But we studied to make it by metal forming. The main focus of this paper is to investigate an optimal forging processes for flare nut using the DEFORM$^{TM}$-3D. commercially available finite element code and tests. Actually an explicit finite element analysis of the flare nut forging processes has been carried out to predict an optimal shape of the flare nut and its results were reflected in the tests of the forging processes design for flare nut. The simulation results which had obtained from finite element analysis were contributed to the forging processes design for flare nut. An optimal shape of nave nut showed agreements with test results. Furthermore. this paper should contribute to a development of the forging process for a variety of parts.s.

• Journal of the Korea institute for structural maintenance and inspection
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• v.3 no.2
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• pp.213-220
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• 1999

The purpose of this study is to apply cathodic protection to reinforced concrete structure and provide fundamental data to prevent the corrosion. The theory of cathodic protection of steel in concrete is to apply sufficient direct current so that corroding anodes on the steel are prevented from discharging ions. Two methods are used to supply the external current. In one, the protected metal is the cathode by connecting it to a more active metal. In the second, an external direct current power source supplies the current. The first is the sacrificial-anode system and the second the impressed-current system. The study results showed that the corrosion of the reinforcing steel in concrete could be enormously decreased by using protective current. The sacrificial anode and concrete nave to be adhered closely each in order to prevent the corrosion of reinforcing steel.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.70.3-70.3
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• 2019

We present a method to estimate 3-component plasma velocity (Vx, Vy and Vz) at solar photosphere near solar disk center, using the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO) called Space-weather HMI Active Region Patch (SHARP). In Heliocentric-Cartesian Coordinates, the component of Vz is obtained from Dopplergram while the components of Vx and Vy are derived from the relation of $B_z{\overrightarrow{u}}=B_z{\overrightarrow{{\nu}_t}}-{\nu}_z{\overrightarrow{B_t}}$ (Demoulin & Berger 2003) using a series of vector magnetograms by an optical flow technique NAVE (Nonlinear Affine Velocity Estimator). This velocity measurement method is applied to AR 12158 producing an X1.6 flare along with a coronal mass ejection. We find noticeable upflow motions at both ends of flux ropes which become a major eruption part, and strong transverse motions nearby them before the eruption. We will discuss the change of plasma motions and magnetic fields before and after the eruption.

• Journal of Educational Research in Mathematics
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• v.8 no.1
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• pp.183-197
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• 1998

Many schools of the secondary level have been recently carrying out 'differentiated class'based on ability grouping between classed(DC). They are usually consisted of three levels; high level available to enriched course, middle level, and low level available to supplemental course. Phrhaps, almost all of the schools might nave executed DC before 2000 year. To do this, a lots of teachers have to develop differentiated teaching and learning materials for themselves. But, these mateirals are usually consisted of differentiated mathematics not on 'content'but on 'items'. So, for the successful 7th differentiated curriculum, the issues such as teaching and learning methods, materials, and evaluation system should be considered in depth focused on DC. .Decide issues related to DC(for example, mathematical contents, methods, activities, class speed,extra)based not on teachers or experts but on students. .Differentiate teaching and learning mateirals according to DC and develop the materials(including guidelines, supplementary books, multimedia, extra) based not on mathematical items but on mathematical contents. .Introduce new mathematical concepts or laws using not only not only definition and explanation but also concrete examples or problems. .Suggest differentiated diverse projects related to mathematical subjects suitable to enhance students` thinking ability to each class. .Have students to develop projects successfully by collecting, representing, analyzing, and interpreting data through communications in a cooperative learning environment.

• Macromolecular Research
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• v.14 no.2
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• pp.140-145
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• 2006

E-science refers to the large-scale science that will increasingly be carried out through distributed global collaborations enabled by the Internet. The Grid is a service-oriented architecture proposed to provide access to very large data collections, very large scale computing resources and remote facilities. Web services, which are server applications, enable online access to service providers. Web portal interfaces can further hide the complexity of accessing facility's services. The main use of synchrotron radiation (SR) facilities by protein crystallographers is to collect the best possible diffraction data for reasonably well defined problems. Significant effort is therefore being made throughout the world to automate SR protein crystallography facilities so scientists can achieve high throughput, even if they are not expert in all the techniques. By applying the above technologies, the e-HTPX project, a distributed computing infrastructure, was designed to help scientists remotely plan, initiate and monitor experiments for protein crystallographic structure determination. A description of both the hardware and control software is given together in this paper.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.67.3-68
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• 2017

Bright rays are often observed after coronal mass ejections (CMEs) erupt. These rays are dynamical structures along which plasmas move outward. We investigated the outflows along the post-CME rays observed by the COR2 on board STEREO Behind on 2013 September 21 and 22. We tracked two CMEs, two ray tips, and seven blobs using the NAVE optical flow technique. As a result, we found that the departure times of blobs and ray tips from the optimally chosen starting height of 0.5 $R{\odot}$ coincided with the occurrence times of the corresponding recurrent small flares within 10 minutes. These small flares took place many hours after the major flares. This result supports a magnetic reconnection origin of the outward flows along the post-CME ray and the importance of magnetic islands for understanding the process of magnetic reconnection. The total energy of magnetic reconnection maintaining the outflows for 40 hr is estimated at 1.4' 1030 erg. Further investigations of plasma outflows along post-CME rays will shed much light on the physical properties of magnetic reconnection occurring in the solar corona.

• The KIPS Transactions:PartB
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• v.9B no.4
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• pp.437-444
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• 2002

There are some important that development of tools to retrieve information by simple operation in large of nave users in the world wide web. In general, query formulation method and operators are variety, not easy to formulate query in information retrieval system or web based retrieval engine. In this paper, we propose "Concept Wizard" to support query formulation with concept term expansion in natural language query information retrieval system. The Concept Wizard are interactively supporting query formulation using thesaurus and Providing plug-in on the web.

• International Journal of Computer Science & Network Security
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• v.23 no.10
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• pp.81-88
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• 2023

In the present scenario, enormous amounts of data are produced every second. These data also contain private information from sources including media platforms, the banking sector, finance, healthcare, and criminal histories. Data mining is a method for looking through and analyzing massive volumes of data to find usable information. Preserving personal data during data mining has become difficult, thus privacy-preserving data mining (PPDM) is used to do so. Data perturbation is one of the several tactics used by the PPDM data privacy protection mechanism. In Perturbation, datasets are perturbed in order to preserve personal information. Both data accuracy and data privacy are addressed by it. This paper will explore and compare several perturbation strategies that may be used to protect data privacy. For this experiment, two perturbation techniques based on random projection and principal component analysis were used. These techniques include Improved Random Projection Perturbation (IRPP) and Enhanced Principal Component Analysis based Technique (EPCAT). The Naive Bayes classification algorithm is used for data mining approaches. These methods are employed to assess the precision, run time, and accuracy of the experimental results. The best perturbation method in the Nave-Bayes classification is determined to be a random projection-based technique (IRPP) for both the cardiovascular and hypothyroid datasets.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.87.2-87.2
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• 2013

We studied a fine-scale half ring-like structure around a pore seen from the high spectral and the high spatial resolution data. Our observations were carried out using the Fast Imaging Solar Spectrograph (FISS) and the InfraRed Imaging Magnetograph (IRIM) installed at the 1.6 meter New Solar Telescope of Big Bear Solar Observatory (BBSO) on 2012 July 19. During the observations, we found a fine-scale half ring-like structure located very close to a pore (~0.4 arcsec apart from the pore). It was seen in the far wing images of the $H{\alpha}$ and Ca II $8542{\AA}$ lines, but it was not seen in the line center images of two lines. The length of the structure is about 4200 km and the width is about 350 km. We determined its line-of-sight velocity using the Doppler shift of the centroid of the Ti II line ($6559.6{\AA}$, close to the $H{\alpha}$ line) and determined horizontal velocity using the NAVE method. we also investigated the magnetic configurations using the Stokes I, Q, U, and V maps of the IRIM. As a results, we found that it has a high blue-shift velocity (~2km) faster than the photospheric features and has a strong horizontal component of the magnetic field. Based on our findings, we suggest that it is associated with small flux emergence, which occurs very close to the pore. Even though it is very small structure, this kind of magnetic configuration can be in chare of the upper chromosphere heating, especially above the pore.

• The Journal of Korean Medicine
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• v.33 no.2
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• pp.47-55
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• 2012

Objectives: This study aimed to investigate the preventive effect of red ginseng (RG) on 5-fluorouracil (5-FU)-induced side effects focusing on myelosuppression. Methods: Rats (n = 50) were divided into five groups, nave, control (ip, 5-FU injection of 150 mg/kg), and RG pre-treatment (po, 25, 50 and 100 mg/kg for 5 days before 5-FU injection). On the $7^{th}$ day after 5-FU injection, we evaluated the effects using peripheral hematological parameters, colony-forming assay, cytokine levels and histopathological finding. Results: The peripheral white blood cell and the differential count were dramatically suppressed by 5-FU, while RG (50 and 100 mg/kg) treatment significantly improved total white blood cell, neutrophil, lymphocyte and platelet counts. Also, RG (100 mg/kg) pre-treatment significantly increased the number of CFU-GM colony compared with the control group. RG pre-treatment also ameliorated the histopathological damage in bone marrow, spleen, stomach and small intestine tissue. Conclusions: These results demonstrate that Korean RG has preventive effects against 5-FU-induced myelotoxicity and gastrointestinal damage.