• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.1
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• pp.62-67
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• 2011

Grinding process is executed in the final machining stage to meet the quality requirements. In generally the ground surface of workpiece is affected by dressing condition as well as grinding condition. In order to estimate the roughness of workpiece, the several roughness models have been researched. These models defined the specific parameters and considered the several parameters which affect to roughness as multiply relationship among them. However, the multiply relationship among parameters is not enough to show the complicated grinding mechanism. Therefore, the neural network algorithm is used in this paper to predict the ground roughness for the plunge grinding. The proposed structure is composed of the initial roughness as well as final roughness model. The input parameters of proposed neural network are referred with the existing roughness model's. The performance of the proposed model is verified through experiments.

• Journal of the Korean Applied Science and Technology
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• v.23 no.1
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• pp.63-69
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• 2006

Methanol and formaldehyde were produced directly by the partial oxidation of methane. The catalysts used were mixed oxides of late-transition metals, such as Mn, Fe, Co, Ni and Cu. The reaction was carried out at $450^{\circ}C$, 50 bar in a fixed-bed differential reactor. The prepared catalysts were characterized by XRD, TPD and BET apparatus. Of the catalysts, A-Mn0.2-6, which contains 0.2 mole of Mn and calcined at $600^{\circ}C$, showed the best catalytic activity: 3.7% methane conversion, and 30 and 28% methanol and formaldehyde selectivities, respectively. The catalytic activity was changed with the content of Mn and the calcination temperature. Catalytic activity increased with the specific surface areas of the catalysts. With XRD, it was found that the structure of the catalysts are changed with calcination temperature. Through $O_2-TPD$ experiment, it was found that the catalysts showing good catalytic activity showed $O_2$ desorption peak around $800^{\circ}C$.

• The Journal of the Korea Contents Association
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• v.9 no.2
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• pp.181-192
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• 2009

Prints in the contemporary art has the radical aspects at not only to maintain the characteristic of printmaking in a field of visual image but also to fulfill and communicate a desire of the public. We can see this from the change of the printmaking forms among the alternation of diverse expression methods and media such as from the line-cut at the Renaissance to colored print process, photography, the beginning of 20th century cartoons, advertisement, art, and graphic poster. From that, we can understand the printmaking as a fluid media, not fixed, has finely accomplished its functions as an act of visual language to smoothly communicate with the individual desire and character than word or language at the complex and various cultural surface. This study is focused on that prints as an avant-garde language in popular culture. Therefore, I have examined the following two aspects. First, with focussing at the specific characters of the graphic posters, I try to define the differences between language and visual language and the effect from it to our emotional perception and behavior with the politic and economic point of view. Second, how has the printmaking art as an fine arts finely accomplished an linguistic action. These are the purpose of this study.

• Journal of Korean Society on Water Environment
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• v.26 no.3
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• pp.497-506
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• 2010

Severe muddy water problem has been the hot issue in Korea. Because of increased nonpoint source pollutions at Kangwon province, best soil erosion management system is required to reduce inflow of nonpoint source pollutions into the waterbodies. The USLE-based SATEEC system have been developed and enhanced for soil erosion and sediment yield estimation. However, the SATEEC cannot estimate soil depositions depending on topography in the watershed, while the USPED estimates soil erosion and deposition using sediment transport capacity of the surface runoff. In this study, the SATEEC and USPED were used to determine soil erosion hot spot subbasins. For this, 54 subbasins were delineated. In general, soil erosion hot spot subbasins were identified similarly with SATEEC and USPED. However, depending on erosion and deposition patterns in each subbasin. USPED estimated soil erosion hot spot subbasins didn't match those estimated with SATEEC. For some subbasins, much deposition was expected than erosion. This indicates that SATEEC estimated soil erosion values may be overestimated for these subbasins. Thus, care should be taken when understanding soil erosion status in the watershed based on USLE-based SATEEC results. In addition, the USPED results could be used to identify the site-specific soil erosion best management practices. If the USPED and USLE-based SATEEC are combined, it would help determining soil erosion hot spot subwatersheds in economic and environmental perspectives.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.525-528
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• 2008

This study is performed to know influence on the hydration according to alkali activator and method of pulverization and fineness in slag-cement. The compressive strength of mortar were examined when the SG powder of which the specific surface area are 4,000, 6,000, and 8000cm$^2$/g were substituted for 50wt.% of ordinary portland cement. Na$_2$SO$_4$, Ca(OH)$_2$, NaOH were used as alkali activator. respectively, As the results, the compressive strength of mortar increased as following the order, Na$_2$SO$_4$>Ca(OH)$_2$>None>NaOH until 7days. But at 28days, mortar used Ca(OH)$_2$ as alkali activator were the highest strength.

• Journal of the Korean Ceramic Society
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• v.53 no.2
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• pp.200-205
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• 2016

With high specific surface area and pore structural diversity, MOFs show important applications in gas storage, catalysis, sensing, separation, and biomedicine. However, the stability of the structure of MOFs has restricted their application and development. In this study, zirconium metal organic frameworks with 9,10-dicarboxylic acid anthracene as ligand, named UIO-66 ($H_2DCA$), were synthesized and their properties and structures were characterized by XRD, SEM, and $N_2$ adsorption. We focus on the stability of the structure of UIO-66 ($H_2DCA$) under different conditions (acid, alkali, and water). The structural changes or ruins of UIO-66 ($H_2DCA$) were traced by means of XRD, TG, and FT-IR under different conditions. The results show that the UIO-66 ($H_2DCA$) materials are stable at 583 K, and that this structural stability is greatly influenced by different types of acid and alkali compounds. Importantly, we found that the structures maintain their stability in environments of nitric acid, triethylamine, and boiling water.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.2
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• pp.237-247
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• 1993

Carbon fiber reinforced plastics(CFRP) have gained increased application in aerospace structures because of their specific strength and stiffness, but are sensitive to impact-induced damage. An experimental investigation was carried out to evaluate the impact resistance of CFRP according to the ply angle. The specimens of angle ply laminate composites were employed with [0.deg. $_{6}$/ .deg.$_{10}$/0.deg.$_{6}$], in which 6 kinds of ply angle such as .deg.=15.deg., 30.deg., 45.deg., 60.deg., 75.deg. and 90.deg. were selected. The impact tests were conducted using the air gun type impact testing machine by steel balls of diameter of 5 mm and 10 mm, and impact-induced damages were evaluated under same impact speed of V=60m/s. The impact damaged zones were observed through a scanning acoustic microscope (SAM). The obtained results were summarized as follows: (1) Delaminations on the interfacial boundaries showed th directional characteristics to the fiber directions. The delamination area on the impact side (interface A) was considerably smaller compared to that of the opposite side (interface B). (2) Cracks corresponding to other delaminations than those mentioned in SAM photographs were also seen on the impact damaged zone. (3) The delamination patterns were affected by the ply-angle, the dimensions of the specimen, and the boundary conditions. (4) The impact damaged zone showed zone showed the delamination on the interfacial boundaries, transverse shear cracks of the surface layer, and bending cracks of the bottom layer.r.r.r.

• Journal of Life Science
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• v.20 no.9
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• pp.1420-1425
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• 2010

Innate immunity is the first line of host defense consisting of various molecules against infectious challenges. Mannose-binding lectin (MBL) belongs to the collectin protein family which takes part of innate immunity and is able to recognize specific carbohydrates on the surface of a variety of infectious agents acting as a pattern recognition molecule. In this way, MBL differentiates self from non-self and interacts with other molecules of the immune system. MBL genotype shows various MBL2 polymorphisms which are responsible for MBL deficiency in a substantial portion of the entire human population and for susceptibility to infectious disease. Therefore, it has been highlighted in the relationship between genetic variants and clinical significance. Here we focus on presenting anoverview of our understanding of MBL structure and functions.

• STI Policy Review
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• v.1 no.3
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• pp.25-37
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• 2010

Advances in Information Communication Technologies (ICT) have demonstrated tremendous potential for solving development challenges and improving development processes, culminating in the new Development 2.0. Many development practitioners have embraced ICT (particularly on Web 2.0 and mobile phone technologies and applications), which have become hot topics in both the development community and the policy community as they engage in development practice and dialogue. Despite this excitement, there lacks among the policy community a robust understanding of the powers and pitfalls of ICT in development, executed actions to back the excited chatter, and dissemination of this understanding to practitioners and policymakers alike. We conducted a literature review, interviewed experts, and engaged in discussion with leaders in international development and science and technology policy to provide an operational framework base in which to view ICT in development. This framework regards ICT as tools that support more effective and efficient community development actions and appropriate consideration of general guidelines, which enable better engagement across and within sectors and individuals. Flexibility and accountability are critical requirements pervading throughout the various actions and guidelines, which promote transparent, partnership-based, and sustainable development. We highlight the strengths and weaknesses of ICT to focus on the cautions to keep ICT access and distribution in context, understand the various levels of technologies and services, and dig below the surface as excitement about ICT increases and threatens to become a short-term solution. We offer ideas for specific programs that policymakers can implement to contribute to a more efficient and effective development process to ultimately support global human development, but stress the endless possibilities that can be explored with creativity and flexibility beyond what is proposed here.

• Korean Journal of Veterinary Service
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• v.30 no.1
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• pp.33-42
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• 2007

Fowl cholera(FC), which has been classified as reportable animal disease in Korea, occurred in the backyard farm located in Chungju, Chungbuk province. The farm was not ordinary domestic poultry farm but backyard farm with main cultivation of fruits. The farmer reported unusual mortality of chickens which were grazed in his own fruit farm without any poultry house. There was a lots of opportunities to contact with wild animals including wild birds freely. Clinical signs observed in the chickens were torticolis, mucous excretion from mouth and greenish diarrhea. On the necropsy we found multifocal necrosis on the surface of liver, hemorrhages in the epicardium and ovary and mucopurulent exudates in the joint. The causative agents was isolated from the liver of chickens collected from the farms and identified as Pasteurella multocida using biochemical tests of bacteria. Also, the isolated bacteria were inoculated into specific pathogen free chickens to evaluate the pathogenicity. High mortality and similar pathological lesions compared to those of chickens died in the farm were observed. We report the first case of fowl cholera of the chickens in Korea and further studies are needed to evaluate the serotype, genotype and pathogenicity of isolated Pasteurella multocida.