• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.10 no.2
• /
• pp.73-78
• /
• 2011

The existent cutting insert have occupied most product of grinding style, because it has a problem of accuracy and manufacturing process. The product has a concept but development is difficult, because grinding and manufacturing by press are impossible. But by development and stabilization of a technology, preference of non-ground insert increases gradually. And then insert that grinding is impossible is developed availably as non-ground product by using developed equipment and software. In this paper reports some experimental results on the machining performance of non-ground Cutting inserts. Three kinds of Cutting inserts were manufactured without using grinding process. Machining experiments were carried out to compare the machining performance of non-ground inserts with that of ground ones. The experimental results indicate that the cutting forces and tool wear and surface roughnesses of machined surface of both ground and non-ground inserts are comparable.

• Journal of KIISE
• /
• v.42 no.11
• /
• pp.1361-1371
• /
• 2015

Depending on the increase amongst various cloud services, the technology of the Cloud Service Broker (CSB) to find the most appropriate services to meet the needs of cloud service consumers has emerged. In order to advance for cloud services to be used through the CSB, it is important to ensure the quality level that meets the demands of consumers through a negotiation process based on the Service Level Agreement (SLA). However, quality metrics of cloud services are different from each other based on the measurement scale, which represents the quality level, and the calculation for each type of cloud services. Therefore, it is necessary to analyze the variability of the quality of cloud services and establish a SLA model for ensuring and improving the level of quality. In this paper, we analyze the quality metrics for the specific type of cloud services by applying the cross-cutting concept and propose a Virtual SLA (VSLA) meta-model.

• Journal of The Korean Association For Science Education
• /
• v.36 no.6
• /
• pp.815-833
• /
• 2016

This study investigated children's (grade 3 to 9) responses to assessment items on energy as a cross-cutting concept in order to get basic information for a learning progression. The assessment consisted of 8 ordered multiple-choice items at the contexts of electric circuit, mechanical energy of falling objects, phase change of matter, dissolution, biological phenomena of a lizard, food chain, radiative equilibrium between Sun and Earth, and the system of water cycling. Children's responses to each item were analyzed with using cross-tabulations in terms of grades and item option levels and Wright map and Differential item functioning based on Rasch modeled item response analysis. The results offered empirical evidence of children's development of understanding energy from relation between energy and its phenomena, types of energy, transfer and conversion of energy, towards conservation and equilibrium of energy for all of eight contexts. Children of each grade did not fully understand energy conservation. As grade goes up, their understandings of energy transfer and conversion were differentiated across the contexts and topics of energy. According to Rasch analysis, children had easier understanding of energy on dissolution and poorer understanding of energy on water cycling than that on other contexts. It was discussed and suggested that the results of this study help us organize science topics with regard to energy when developing new national science curriculum.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1996.11a
• /
• pp.9-14
• /
• 1996

The deflection of an end mill is very important in machining process and cutting simulation because it affects directly workpiece accuracy, cutting force, and chattering. In this study, the deflection of the end mill was studied both experimentally and by using finite element analysis. And the moment of inertia of radial cross sections of tile helical end mill is calculated for the determination of the relation between cross section and rigidity of tile tools. Using tile Bernoulli-Euler beam and and the concept of equivalent diameter, a deflection model is established, which includes most influence from tool geomety parameters. It was found that helix angle attenuates the rigidity of the end mill.

• Journal of the Korean Society for Precision Engineering
• /
• v.14 no.12
• /
• pp.143-152
• /
• 1997

The deflection of an end mill is very important in machining process and cutting simulation because it affects directly workpiece accuracy, cutting force, and chattering. In this study, the deflection of the end mill was studied both experimentally and by using finite element analysis. And the moment of inertia of cross sections of the helical end mill is calculated for the determination of the relation between geometry of radial cross section and rigidity of the tools. Using the Bernoulli-Euler beam theory and the concept of equivalent diameter, a deflection model is established, which includes most influences from tool geomety parameters. It was found that helix angle attenuates the rigidity of the end mill by the finite element analysis. As a result, the equivalent diameter is determined by tooth number, inscribed diameter ratio, cross sectional geometry and helix angle. Because the relation betweem equivalent diameter and each factor is nonlinear, neural network is used to decide the equivalent diameter. Input patterns and desired outputs for the neural network are obtained by FEM analysis in several case of end milling operations.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2001.04a
• /
• pp.1085-1088
• /
• 2001

The process of styrofoam pattern that has been used for material of press die pattern depends chiefly on handwork. Laser manufacturing system developed to increase precision and efficiency of process that is also able to convert the design easily. Applying the RP(rapid prototyping) concept reversely, the unnecessary part of section is vapored away by heat source of laser beam after converting 3-D CAD model into cross-sectional shape information. Laser beam is line-scanned in plane specimens to measure the depth and width of cut, surface roughness, cross-sectional shape as converting laser power, scanning speed, cutting gas pressure. With these basic data, plane surface, inclined surface, hole, outer contour trimming process is experimented and optimum condition are obtained. In plane and inclined surface experiments, 15W laser power and 50mm/s scanning speed make superior processing property and 30W, 10mm/s make processing efficiency increase in trimming process. With these results, simple patterns were manufactured and the possibility of applying laser manufacturing system to styrofoam pattern was convinced.

• SUVANNABHUMI
• /
• v.14 no.2
• /
• pp.207-231
• /
• 2022

From being understood as a dwelling, the concept of home is extended to denote belongingness and a sense of attachment in which spiritual, ethnic, religious and historical identities shape a sense of self. Hence, home with its expanded definitions is considered as a cross-cutting and fundamental theme in works by Võ Phiến, one of the diaspora's towering minds who devoted his life to capturing the rich details of Vietnamese culture, its villages and locals. This article pays attention to the cultural space created through Võ Phiến's tuỳ bút written when he lived in Saigon and California. Many representations of home were argued as evidence of subtle influences of the historical and social context on the way Võ Phiến perceived and built his own homeland. By observing disruption and continuity through the expressions of the home in Võ Phiến's writing, we shed light on how Võ Phiến managed to create an indigenous cultural space towards social interactions of Western ideology in South Vietnam from 1964 to 1975.

• Proceedings of the KIEE Conference
• /
• 2002.11c
• /
• pp.75-78
• /
• 2002

SFFS(Solid Freeform Fabrication System) is commercializing to rapid prototyping concept in world-wide some corporations including the States, have much technological problems yet and need new mode for agile solid freeform fabrication as well as prototyping. In this paper, we design an automatic control algorithm that the cutting path of laser beam, on the SFFS, is controlled with constant speed. The designed algorithm for constant-speed path control is implemented and experimented in the $CAFL^{VM}$ (Computer Aided Fabrication of Lamination for Various Material) system, the new SFFS which is developed in this paper. Its process is an automated fabrication method in which a 3D object is constructed from STL(SToreoLithography) 2D data, derived from CAD 3D image, by sequentially laminating the part cross-sections. The constant-speed path control is started from the STL data. After STL file is modified in data format to be available for control. The fabrication of the 2D part is, with constant speed, conducted from the 23 position data by laser beam. we confirm its high-performance through experiment results from the application into $CAFL^{VM}$ system.

• Journal of the Speleological Society of Korea
• /
• no.61
• /
• pp.65-82
• /
• 2000

The remarkable development of information technology today is significantly increasing the desire for related services as it allows one to process and transmit information fast and accurately as well as in an efficient way. Particularly, the spread of the Internet even changes our life pattern, not to mention allowing us to provide or share information. One of the most typical example is electronic commerce. The e-commerce industry, which is build upon informations super high way, is growing rapidly, backed on the development of communications technology and the combination of various media. Companies are active In embracing and utilizing the cutting-edge information technology, whereas the tourism industry in general is still at a rudimentary stage. Therefore, it is expected that the industry will harness e-commerce in many aspects. Tourism, in its characteristic, has a variety of sectors, and cross-sector cooperation is essential. Therefore, the industry can provide better services by connecting or integrating network systems and taking advantage of e-commerce, while it is of no less importance to have informal ion system for promoting products. This thesis will look into and the basic concept and role of e-commerce as well as the existing tourism information system. It will also study ways to make good use of e-commerce by adopting it into the tourism information system.

• Journal of The Korean Association For Science Education
• /
• v.35 no.4
• /
• pp.677-689
• /
• 2015

The purpose of this study is to derive suggestions and implications to strengthen the science curriculum continuity of Korea through comparative analysis with focus on the continuity of science curriculum in six countries (Taiwan, the United Kingdom, Finland, the United States, Canada, Korea). Original and Korean translations of the national curriculums of each country gathered from NCIC comparatively analyzed the contents of the 'Moon' and 'Rock cycle' based on features of curriculum configuration, vertical, and lateral connectivity. As a result, it was found that the concepts of Big Ideas or Cross-cutting Concept was utilized internationally to strengthen the linkage between grades or subjects. In particular, dealing with the aspect of the system was important. In the comparison of countries for the content, Korea deals with the most frequency on the 'Moon' and 'Rock cycle'. The contents of the chapter about the moon were simply repeated from elementary to high school levels with some variation. Korean science curriculum holds different perspectives and contents about the Rock cycle compared to other countries. In conclusion, Korea's curriculum requires appropriate tools to strengthen curriculum linkage and by doing so, it will be able to take advantage of the systems approach. Moreover, it is important to constitute the curriculum based on a sufficient understanding of the learning development of students according to their grade levels for the effective application of the curriculum.