• Proceedings of the KSR Conference
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1037-1043
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• 2007

The railroad systems with the ballast tracks have been widely used for a long time. But recently, the use of the slab track is being increased gradually with a technical developments. So, this paper deals with the appliance of the slab tracks on the railroad bridges. Firstly, review the design criteria of the railroad bridges related to the slab tracks for the stability and serviceability, based on DIN and EURO code. Then, perform the analysis of the railroad prestressed concrete bridges, and check whether the results of the analysis satisfy the design criteria. Finally, find the construction condition of bridges that all the design criteria are satisfied. As a result, to maintain the stability and serviceability of the bridges, bridges must have some restrictions, including a time of installation of the slab tracks. So, the construction schedule for the erection of the bridges will be carefully considered in case of the concrete railroad bridges with the slab tracks.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제13권2호
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• pp.109-121
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• 2009

In this paper, we use He's polynomials for solving higher order integro differential equations (IDES) by converting them to an equivalent system of integral equations. The He's polynomials which are easier to calculate and are compatible to Adomian's polynomials are found by using homotopy perturbation method. The analytical results of the equations have been obtained in terms of convergent series with easily computable components. Several examples are given to verify the reliability and efficiency of the proposed method.

• Natural Product Sciences
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• 제3권1호
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• pp.42-48
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• 1997

The roots of Tabernaemontana macrocarpa Jack (Apocynaceae) yielded nine indole alkaloids which were identified as coronaridine (2), voacangine hydroxy-indolenine (3), 3-oxo-coronaridine (4), 19-R-heyneanine (7), coronaridine pseudoindoxyl (8) and voacangine pseudoindoxyl (9) while 3-(2-oxopropyl)-coronaridine (1), 3-(2-oxopropyl)-coronaridine-pseudoindoxyl (5) and 3-(2-oxopropyl)-voacangine-pseudoindoxyl (6) were isolated as artefacts formed during the isolation process. All of the alkaloids were identified by spectroscopic methods $(UV,\;MS,\;^1H-NMR\;&\;^{13}C-NMR)$ and in comparison with the literature data.

• Proceedings of the Korean Geotechical Society Conference
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.331-338
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• 2001

The soil-steel bridges which were introduced in Korea recently are widely used instead of underpasses of highway or small bridges. This bridge is a kind of flexible buried conduit which sustain the applied load by the interaction with the backfill soil. The 6.25m din. round soil-steel bridge was instrumented so as to investigate the behavior of load sustenance, The axial forces and moments at the 7 locations around the metallic shell were calculated from the measurement of strains during backfilling. The maximum axial force and moment were compared with those of various design predictions. Finally, the stability of bridge was evaluated.

• Journal of The Korea Institute of Healthcare Architecture
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• 제13권4호
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• pp.25-35
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• 2007

In Germany, community based daycare facilities has been supported by long term care policies since the 1970s. With the legislation of Care Insurance, those policy has been developed further. As the use of daycare facilities decreased and the financial burden for consumers increased, administrators of facilities has been seeking for innovative programs and management methods in order to improve the service. For the same reason, policy makers have been pursuing new regulations of architectural standards of facilities. By looking at legislations (i.e., Law of Care Insurance, Law of Heim, and DIN18025) that stipulate architectural standard of facilities in Germany, this study will identify the development process of architectural change of daycare facilities. In addition, the study aims to contribute to the discussion on the use of day care facilities in Korea in terms of the legislation of Care Insurance soon to be introduced.

• Journal of applied mathematics & informatics
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• 제27권5_6호
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• pp.1343-1359
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• 2009

In this paper, we implement a relatively new analytical technique by combining the traditional variational iteration method and the decomposition method which is called as the variational decomposition method (VDM) for solving the sixth-order boundary value problems. The proposed technique is in fact the modification of variatioanal iteration method by coupling it with the so-called Adomian's polynomials. The analytical results of the equations have been obtained in terms of convergent series with easily computable components. Comparisons are made to verify the reliability and accuracy of the proposed algorithm. Several examples are given to check the efficiency of the proposed algorithm. We have also considered an example where the VDM is not reliable.

• Journal of applied mathematics & informatics
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• 제27권5_6호
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• pp.1265-1277
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• 2009

In this paper, we apply a new decomposition method for solving initial and boundary value problems, which is due to Noor and Noor [18]. The analytical results are calculated in terms of convergent series with easily computable components. The diagonal Pade approximants are applied to make the work more concise and for the better understanding of the solution behavior. The proposed technique is tested on boundary layer problem; Thomas-Fermi, Blasius and sixth-order singularly perturbed Boussinesq equations. Numerical results reveal the complete reliability of the suggested scheme. This new decomposition method can be viewed as an alternative of Adomian decomposition method and homotopy perturbation methods.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.851-856
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• 2003

The study on the new measurement method of room acoustics is now in process in the ISO TC43/SC2/WG24 New standard(WD 18233) is dealing with the MLS, swept sinusoidal signal and impulse. This working group is composed of more than 20 specialists in 10 countries and the convener is professor J.H.Rindel in technical university of Denmark. The meeting of WG24 was held in the DIN, Berlin at 23rd. this september and the results was sent to the secretary of ISO TC43/SC2 for the circulation. Brief information of ISO/WD18233 and the result of this meeting is given here.

• Journal of Korean Society of Transportation
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• 제14권2호
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• pp.31-44
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• 1996

This study focuses on the evaluation of the streets on residential areas. For this purpose, pedestrain and vehicle occupancy indicators on residential areas are proposed, and vehicle, pedestrain flow and status of on-street parking on residential streets are analyzed. Also, according to the suggested occupancy indicator, occupancy status of pedestrain and vehicle are identified. At the end, evaluation of residential streets are conducted. The suggested occupancy indicator is a quantitative indicator which can represent the traffic situation on street. It can also be represente din the same dimension among pedestrain, vehicle flow, packed vehicle. Also, occupancy indicator can be utilized for the allocation and evaluation of transportation modes on residential street. Except on-street parking during the day time, moving vehicle occupancy rate contains the more than 80 precent when it is estimated based on the vehicle flow and pedestrain only. As the streets on residential area are occupied by the pedestrain approximately 20 percent during the day time, it is identified quantitatively that the necessity of space for pedestrain.

• Journal of The Korean Association For Science Education
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• 제22권5호
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• pp.1044-1070
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• 2002

Initial science teacher education in Hong Kong is provided by the Post-graduate Diploma in Education Programme (PGDE) for both pre-service and in-service secondary school teachers. This programme includes a balanced treatment of subject curriculum and teaching in science, general pedagogical knowledge and skills, educational psychology and school administration. The science courses in this programme also have some units that equip science teachers with the knowledge and skills that are essential for teaching a science curriculum that emphasises conceptual change and understanding of the nature and methods of science. This emphasis is illustrated by two studies: (1) Developing a conceptual change model of instruction in Biology teachers, and (2) Constructing understanding of the nature and methods of science.