• Journal of Electrical Engineering and Technology
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• v.9 no.3
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• pp.888-892
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• 2014

In the design of the rotor of an interior permanent magnet synchronous motor (IPMSM), the bridge between the permanent magnets helps prevent the scattering of permanent magnets and pole pieces during high-speed operation. In the design of a motor, if the bridge is too thick, its performance will be largely degraded because of flux leakage. Additionally, if the bridge is too thin, its mechanical safety cannot be guaranteed. Thus, an accurate analysis method is required to determine the thickness of the bridge. Conventional stress analysis methods determine the thickness of the bridge by only considering the centrifugal force of the rotors. In this study, however, a method that additionally considers the radial force generated by the air-gap flux density based on the conventional methods is proposed and reflected in the design of a traction motor for electric vehicles. Finally, the validity of this study is verified through a reliability test related to high-speed operation.

• Clinical and Experimental Pediatrics
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• v.52 no.8
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• pp.851-855
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• 2009

Death is not only a medical problem; it is also an ethical problem. When doctors face a dying neonate, their knowledge of bioethics and the opinions of ethical specialists and religious leaders are helpful for them and the family of the dying baby. In recent years, due to the increase of surviving babies who have suffered from severe illness, those born too small or too early, and those with severe anomalies in neonatal intensive care unit (NICU), we have met with complicated bioethical problems frequently. To lessen the burdens of doctors and the parents of the dying baby, I reviewed medical, ethical and religious articles about bioethics in adult death. My suggestions are listed as follows: 1) regular bioethical education and activation of bioethical committees in NICU, 2) a well-controlled nationwide database, 3) a hospice unit space and programs for dying baby in NICU, and 4) social support for pregnant women and financial support for the NICU.

• Korean Journal of Computational Design and Engineering
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• v.10 no.1
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• pp.11-16
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• 2005

CAD/CAM system may have such advantages of cost reduction, production time shortening, and product quality improvement. But current advanced versions of CAD/CAM system for 3-D NC data generation are too much expensive to purchase and too difficult to make full use for small-scale manufacturers whose main products are of 2-D simple shapes. The objective of this paper is to introduce a cost-effective way to 2-D NC data generation with a widely spread CAD software. Using VISUAL LISP in the well-known AUTO-CAD, the contents and steps of an automatic NC data generation program are presented for 2-D machining of contours and pockets. To approve the usefulness of program, a test application to a real part is exhibited also.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.624-627
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• 1992

Mathematical modeling is majorly divided into three parts: the derivation of models, the fitting of models to data, and the simulation of data from models. This paper focuses on the parameter optimization which is necessary for the fitting of models to data. The method of simulated annealing(SA) is a technique that has recently attracted significant attention as suitable for optimization problem of very large scale. If the temperature is too high, then some of the structure created by the heuristic will be destroyed and unnecessary extra work will be done. If it is too low then solution is lost, similar to the case of a quenching cooling schedule in the SA phase. In this study, therfore, we propose a technique of determination of the starting temperature and cooling schedule for SA phase.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.122-125
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• 2008

Sensors used in many USN (Ubiquitous Sensor Network) domain applications generate a large amount of sensor stream data. The volume of sensor stream data is too huge to store the whole data and data speed is too fast to control each of them. In order to provide rapid and reliable context analysis service over sensor stream data, we propose a WHEN-DO context analysis model that supports the functionality of sliding window. This model is designed to be used as follows: If the sensor stream data satisfies condition in 'WHEN' clause, then it will execute actions in 'DO' clause in WHEN-DO context analysis model. The proposed WHEN-DO context analysis model can be applied to many other USN environment applications such as monitoring the status of a building and then taking actions in corresponding context condition.

• The Korean Journal of Applied Statistics
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• v.25 no.4
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• pp.661-668
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• 2012

For displaying multivariate numerical data on a 2D plane by the projection, principal components biplot and the GGobi are two main tools of data visualization. The biplot is very useful for capturing the global shape of the dataset, by representing $n$ observations and $p$ variables simultaneously on a single graph. The GGobi shows a dynamic movie of the images of $n$ observations projected onto a sequence of unit vectors floating on the $p$-dimensional sphere. Even though these two methods are certainly very valuable, there are drawbacks. The biplot is too condensed to describe the detailed parts of the data, and the GGobi is too burdensome for ordinary data analyses. In this paper, "the local projective display(LPD)" is proposed for visualizing multivariate numerical data. Main steps of the LDP are 1) $k$-means clustering of the data into $k$ subsets, 2) drawing $k$ principal components biplots of individual subsets, and 3) sequencing $k$ plots by Hurley's (2004) endlink algorithm for cognitive continuity.

• Journal of the Korean Graphic Arts Communication Society
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• v.19 no.1
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• pp.42-54
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• 2001

The combination of a silicone surfaced plate and high viscosity ink produced a waterless printing system that worked well, but had limitation. The limitation was that this system was restricted to relatively short run lengths. In the waterless printing process, the press tended to heat up rapidly. Heat in turn, broke down the resins in the inks, causing them to become more fluid. When the ink is heated, the viscosity will drop, the ink will become too liquid and the plate will no longer be able to resist it. The ink will adhere to the non-print portions of the plate, and will print as a very fine mist or speckle pattern in the non-image area. On the other hand, when the ink gets too cold, viscosity will increase until ink transfer is impeded. This study carried otu to investigate the effect of temperature variations of the inks on the print quality in waterless lithography and to examine the adaptability of waterless lithography to conventional offset press without cooling system.

• Nuclear Engineering and Technology
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• v.43 no.1
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• pp.75-82
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• 2011

The neutron multiplication factor in spent fuel storage racks, in which a stainless steel plate encloses a fuel assembly, was evaluated according to the variation of distance between the fuel assembly and stainless steel plate, as well as the pitch. The stainless steel plate position with the lowest multiplication factor on each pitch consistently appeared as 6mm or 9mm away from the outmost surface of the fuel assembly. Because the stainless steel plate has a thermal neutron absorption cross section, its ability to absorb neutrons can work best only if it is installed at the position where thermal neutrons can be gathered most easily. Therefore, the stainless steel plate position should not be too close or too far away from the fuel assembly, but it should be kept a pertinent distance from the fuel assembly.

• Journal of Biomedical Engineering Research
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• v.35 no.2
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• pp.19-25
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• 2014

According to recent data more than 80% of people suffer from back pain, due to an aging and a poor posture, at least once in their life time, and 7~10% of them have chronic spine illness. Researchers over the years have studied on various spinal traction devices that utilize the force of traction, and have also reported clinical test results. However, most existing devices are too complicated and too expensive. In order to solve these problems, we have developed a new device in which the frame moves up and down and at the same time tilting angle of the frame is adjusted. We have analyzed the forces applied on the body as a function of tilting angle. And the result shows that the new device has achieved the force of traction, which is known to be effective for spinal rehabilitation.

• International Journal of High-Rise Buildings
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• v.7 no.2
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• pp.127-140
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• 2018

The skylines of many cities worldwide are still defined by the dominant and ubiquitous office blocks of the twentieth century. While there is consensus stating that future tall building typologies should depart substantially from these past models, the inheritance of large and obsolete tall office building stocks presents a problem of global significance. Too old for present corporate models, but too new for gaining public historical importance, the twentieth-century office tower is a typology under threat of extinction. However, the need for a culturally informed strategy of preservation for that generation of tall buildings is seldom advocated. Drawing evidence from the case of Melbourne, Australia, this article presents a methodological pathway to overcome pitfalls of memory and interpretation, which commonly prevent an unbiased assessment of the value and urban contribution of late-twentieth-century skyscrapers.