• 한국도로학회:학술대회논문집
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• 2010.09a
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• pp.99-107
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• 2010

A permanent deformation model was developed in this study based on the shear properties of asphalt mixtures such as cohesion and friction angle. Triaxial compressive strength (TCS) and repeated load permanent deformation (RLPD) tests on the three types of asphalt mixtures are performed at various loading and temperature conditions to correlate shear properties of asphalt mixtures to rutting performance. It is observed from the tests results that the ratio of shear stress to strength accurately identifies the mixture rutting performance. It could take care of not only mixture types but also load and temperature conditions dependences. Three different versions of the permanent deformation model based on different input levels are proposed and verified using the tests data. The proposed model based on the ratio of shear stress to strength can successfully predict the permanent deformation of various asphalt mixtures all the way up to the 10% of permanent strain including all three stages of permanent deformation in a wide range of loading and temperature conditions without changing model coefficients.

• Textile Coloration and Finishing
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• v.24 no.1
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• pp.27-32
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• 2012

Generally, hair treatments by complementary actions to give a sense of activity are permanent setting, dyeing, and bleaching, etc. In this study, we investigated the wave formation ability and hair damage occuring in permanent setting and bleaching process. The wave formation ability was evaluated by the differences of length and curl diameter after permanent setting. And the hair damage was also evaluated by the protein release ability and SEM of hair. The bleached hair immediately after permanent setting treatment has better wave formation ability, but much more damaged than the bleached hair after rinsing thoroughly with warm water. It was considered that the chain of hair keratin broke down easily by the bleaching action in the existence of permanent setting agents.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10b
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• pp.906-911
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• 1998

This study is about an application of permanent form to the field. The present problem of this country's building market in the face of 3D, in addition to construction cost increase, materials lack problems and opening a building market to foreign countries, is trying to find out the efficient ways of overcoming these problems. So the efficacy of form work to technical improvement will contribute a practical permanent form in field through scientific test of the design and construction of permanent form. According to the result of these experiments, they seemed to be a permissible error range of Permanent form ± 5mm and steel reinforcing of Permanent form seemed to be ±5mm. a modification of Permanent form is superior to any wooden form.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.2
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• pp.53-58
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• 2001

This paper describes a moving mesh technique for dynamic characteristics analysis of permanent magnet linear synchronous motor with the secondary aluminium sheet. The moving mesh technique applied to the linear induction motor can be used to analyze the linear synchronous motor with the rectangular permanent magnet. But in case of the permanent magnet with taper, the shape of the permanent magnet is presented. The time-stepped finite element method is used for the dynamic characteristics simulation of the permanent magnet linear synchronous motor, The results of application example(hysteresis current controlled inverter fed control) such as thrust, current and flux plots are shown.

• Honam Mathematical Journal
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• v.28 no.4
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• pp.521-531
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• 2006

In this paper, we construct a procedure of Maple programming for (0, 1)-matrix with a prescribed permanent, $1,2,...,2^{n-1}$. An application of such construction is given, and we obtain the some results of (0, 1)-matrices with the permanent less than or equal to n! by replacing elements 0's by 1's.

• Bulletin of the Korean Space Science Society
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• 2002.10a
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• pp.35.2-35
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• 2002

• Bulletin of the Korean Mathematical Society
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• v.36 no.3
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• pp.459-465
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• 1999

In this paper, we represent the permanent of a matrix A as inner products of some vectors or functions by noting that the permanent of A equals certain coefficients of some polynomials associated with A.

• Journal of Families and Better Life
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• v.25 no.5
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• pp.185-197
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• 2007

Permanent rental housing which is entirely financed by the Government is welfare housing for those who fall within the lowest income bracket. This type of housing is intended for use as rental housing on a long-term basis. At present, there are about 190,000 permanent rental housing units in Korea. The purpose of this study is to suggest the implications to improve the management and welfare service system of permanent rental housing. For this, qualitative data were collected by using the in-depth interview with staffs of community welfare center and management office of five permanent rental housing complexes and two times of advisory committee meeting with housing and social welfare experts. To analyze the data gathered in this study, the constant comparative method of data analysis was used. Conflicts between the management office and social welfare center of permanent rental housing could be classified into two aspects; personal and operational. Main reasons for the conflicts between two institutions were identified such as attitude of management office staffs, lack of cooperation, current administrative system, lack of management resources such as space and operation cost, and so on. Based on the results, some implications including institutional support and social complementary cooperation were suggested for improvement of management and welfare service system for the residents of permanent rental housing.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2310-2316
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• 2011

In order to apply Interior Permanet Magnet Synchronous Motor(IPMSM) to the propulsion system of the railway transit, 110 (kW) class IPMSMs with high-power density are designed as a concentrated winding model and a distributed winding model in this study. The concentrated winding model designed in this study is 6 poles/9 slots and the distributed winding model is 6 poles/36 slots. In general, the eddy current losses in the permanent magnets of IPMSM are caused by the slot harmonics. The thermal demagnetization of the magnet by the eddy current losses at high rotational speed often becomes one of the major problems in the IPMSM with a concentrated windings especially. A design to reduce eddy current losses in permanent magnets design is important in IPMSM for the railway vehicle propulsion system which requires high-speed operation. Therefore, a method to devide the permanent magnet is proposed to reduce the eddy current losses in permanent magnet in this study. Authors analyze the variation characteristics of the eddy current losses generated in permanent magnet of the concentrated winding model by changing the number of the division of the permanent magnets.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.3
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• pp.143-151
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• 2004

High-speed permanent magnet machines are likely to be a key technology for electric drives and motion control systems for many applications, since they are conductive to high efficiency, high power density, small size and low weight. In high-speed machines, the permanent magnets are often contained within a retaining sleeve. However, the sleeve and the magnets are exposed to high order flux harmonics, which cause parasitic eddy current losses. Rotor losses of high-speed machines are of great importance especially in high-speed applications, because losses heat the rotor, which is often very compact construction and thereby difficult to cool. This causes a danger of demagnetization of the NdFeB permanent magnets. Therefore, special attention should be paid to the prediction of the rotor losses. This paper is concerned with the rotor losses in permanent magnet high-speed machines that are caused by permeance variation due to stator slotting. First, the flux harmonics are determined by double Fourier analysis of the normal flux density data over the rotor surface. And then, the rectilinear model was used to calculate rotor losses in permanent magnet machines. Finally, Poynting vector have been used to investigate the rotor eddy current losses of high-speed Permanent magnet machine.