• 대한토목학회논문집
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• 제14권4호
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• pp.711-719
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• 1994

본 논문은 철근콘크리트 구조물의 해석시 부착슬립의 효과를 효율적으로 고려하기 위한 새로운 알고리즘의 개발에 관한 것으로 2중절정을 사용해야 하는 기존의 고전적인 부착요소와는 달리 부착슬립 효과를 고려한 철근의 등가강성을 산정하므로써 2중절점의 고려없이 부착슬립 효과를 고려할 수 있도록 도모하였다. 또한 콘크리트 변위를 산정한 후 철근의 각 절점에서 힘과 변위의 평형관계와 철근과 콘크리트 사이의 관계식을 이용하여 구성된 관계식을 토대로 철근요소의 각 절점변위와 부재력을 첫번째 철근요소부터 역으로 산정하는 반복해석 과정을 통해 최종 결정하게 된다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권6호
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• pp.3581-3585
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• 2013

Background: Accurate statistics on the cancer burden are essential, both for purposes of research and for setting priorities in healthcare management. So that in vast countries with partial registration coverage, such as Iran, local data are more useful. We here estimated the incidence, prevalence and mortality time trend of four major cancer site, lung, stomach, breast and prostate, over the period 2001-2010 and provided short-range projections to 2015 in Isfahan. Materials and Methods: Estimates were derived by applying the mortality-incidence analysis method, a back-calculation approach to estimate and project incidence, prevalence and mortality of chronic degenerative disease, starting from knowledge of mortality and relative survival information. Results: Age adjusted incidence, mortality and prevalence rates in Isfahan exhibited a clear upward trend for all four sites during the period 2001-2015, with marked increasees in prostate and breast predicted for the future. Difference in incidence trends between males and females might be attributable to the difference in risk factors specific to certain cancer sites, with smoking being the main risk factor. Conclusions: In this study, males and females displayed an increasing pattern for incidence and mortality rate over the entire study period until 2015. This information can be used as basis for planning healthcare management and allocating recourses in public health.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.612-617
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• 2001

This paper reports the cooling performance of a PDP(plasma display panel) with a heat spreader by means of numerical analysis. Due to the simplifications and assumptions inherent in the analysis, computed results are found to differ those of the experiment by 13%. Calculation shows a maximum temperature of $65^{\circ}C$ for the plasma glass, as opposed to the allowable temperature of $90^{\circ}C$, producing a temperature difference of $25^{\circ}C$ between the upper and lower regions. This is enough to cause cracks in the plasma glass. In order to avoid this, more ventholes are added at the upper center region of the back cover, thereby causing a $3^{\circ}C$ drop in the maximum temperature, which reduces the temperature difference to $12^{\circ}C$. The new design gives more uniform temperature distribution across the plasma glass.

• 한국수소및신에너지학회논문집
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• 제20권3호
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• pp.256-263
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• 2009

The operating range of HCCI engine is narrow due to excessive rate of pressure rise on high load. The fuel stratification is proposed to solve the problem. The purpose of this study is to gain a better understanding of the effects of fuel stratification on reducing the pressure-rise rate at high load in HCCI combustion and to investigate that the operating range is expanded for fuel stratification in the preceding condition of initial temperature and equivalence ratios. The engine is fueled with Di-Methyl Ether (DME) which has unique 2-stage heat release. The computations were conducted using SENKIN application of the CHEMKINll kinetics rate code. Calculation result shows that proper fuel stratification prolongs combustion duration and reduce pressure rise rate.

• 대한기계학회논문집
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• 제16권7호
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• pp.1332-1340
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• 1992

본 연구에서는 제어기에 관심을 갖던 기존의 방법에서 탈피해서 포화요소에 촛점을 맞추어 와인드업 현상을 해결하는 방법을 제시하고자 한다. 이 방법은 단입 출력 시스템에서는 역계산방법(back calculation method)과 동일하나 제어기와 보상기 를 분리하여 설계한 후 보상기를 각각의 엑추에이터 앞에 설치함으로써 다입 출력 시 스템에 쉽게 적용될 수 있다는 점에서 새로운 제안이라 할 수 있다. 또한 제어기를 바꾸지 않고도 보상기만을 추가로 설치하여 와인드업을 방지할 수 있으므로 이미 설치 된 시스템에의 적용이 용이함도 특기할 만하다.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2004년도 추계학술발표대회 개요집
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• pp.58-60
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• 2004

In the field of welding the behavior of a welded structure under consideration may be predicted via heat transfer and residual stress analysis. In order to facilitate the industrial applications of welding, numerical modeling of heat transfer and residual stress in weldment has been carried out applying Finite Element Method (FEM) and the analysis with the external load including this residual stress due to welding has been done. The present work includes the specialized finite element codes for the calculation of nonlinear heat transfer details and residual stress redistributed along with the external load in the welded structures. A basic interface, which allows models, built in commercial preprocessing package access to the data necessary to build standard input decks for these specialized FEM codes, which are not supported by commercial package. The results from the FEM codes are imported back into commercial package for visualization. In addition the residual stress values are exported to commercial package (such as ANSYS, PATRAN etc.) for further analysis with the external loads, which make the FEM codes fully applicable to the industrial purpose.

• Journal of Advanced Research in Ocean Engineering
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• 제3권2호
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• pp.59-65
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• 2017

When an anchor is dropped into the sea, there exists a danger of collision on the pipeline and subsea cables in the seabed. This collision could cause huge environmental disasters and serious economic losses. In order to secure the safety of subsea structures such as pipelines and subsea cables from the external impact, it is necessary to estimate the exact external force through the anchor's terminal velocity on the water. FLUENT, a computational fluid dynamic program, was used to acquire the terminal velocity and drag coefficient computation. A half-symmetry condition was used in order to reduce the computational time and a moving deforming mesh technique also adapted to present hydrostatic pressure. The results were examined with the equation based on Newton's Second Law to check the error rate. In this study, three example cases were calculated by stockless anchors of 5.25 ton, 10.5 ton, and 15.4 ton, and for the onshore experiment dropped height was back calculated with the anchor's terminal velocity in the water.

• 전기학회논문지
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• 제62권10호
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• pp.1403-1407
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• 2013

This paper presents the method to calculate the motor parameters considering skew in EPS Interior Permanent Magnet Synchronous Motor (IPMSM). The skew is applied to stator or rotor by general technology used for design of reducing noise and vibration in motor. The characteristics analysis of motor including the skew is mostly used by 3D Finite Element Analysis (FEA), though, this analysis is a very time-consuming to perform. Besides, The reliability lacks due to the considerable change of motor characteristics according to the number of elements in 3D FEA. However, analysis time and effort can be saved by characteristic analysis considering skew using 2D FEA. Therefore, in this paper, a quick and accurate method for the calculations of motor parameters considering skew is suggested. The proposed method is verified by the comparison of calculated and experimental results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 A
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• pp.171-174
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• 2003

In this paper, a Learning module for a reconfigurable neural network processor(ERNIE) was proposed for an On-chip learning. The existing reconfigurable neural network processor(ERNIE) has a much better performance than the software program but it doesn't support On-chip learning function. A learning module which is based on Back Propagation algorithm was designed for a help of this weak point. A pipeline structure let the learning module be able to update the weights rapidly and continuously. It was tested with five types of alphabet font to evaluate learning module. It compared with C programed neural network model on PC in calculation speed and correctness of recognition. As a result of this experiment, it can be found that the neural network processor(ERNIE) with learning module decrease the neural network training time efficiently at the same recognition rate compared with software computing based neural network model. This On-chip learning module showed that the reconfigurable neural network processor(ERNIE) could be a evolvable neural network processor which can fine the optimal configuration of network by itself.

• 전기학회논문지P
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• 제58권3호
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• pp.316-322
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• 2009

This paper presents an analytical design method of a passive harmonic filter for a three-phase diode rectifier and uses a new transfer function approach in the analysis and design. The transfer function approach derives an analytical formulation of an utility system including passive filters with a basis of Laplace transform and provides a graphical formulation so that a visualized insight into an interaction between individual filter and system response can be attainted. Harmonic impedance, voltage division and current division transfer function are used as a design tool, which makes a calculated filter parameters to satisfy IEEE-519 distortion limits. A simple five-step design procedure is introduced in the filter design, which consists of system analysis, selection of PCC(Point of Common Coupling), filter specification calculation, appropriate filter design for system and filter implementation. Philosophy governing the design procedure is based on a numerical/graphical iterative solution, trial and error with visualization feed-back based on "algebra on the graph". Finally, performance of the designed passive harmonic filter is verified by experiment and shows that 5th, 7th, 9th, 11th and 13th harmonics are decreased within IEEE-519 distortion limits, respectively.