• Coupled systems mechanics
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• 제9권4호
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• pp.343-358
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• 2020

The present research deals with the time-harmonic deformation in transversely isotropic magneto thermoelastic solid with two temperature (2T), rotation due to inclined load and laser pulse. Generalized theory of thermoelasticity has been formulated for this mathematical model. The entire thermo-elastic medium is rotating with uniform angular velocity and subjected to thermally insulated and isothermal boundaries. The inclined load is supposed to be a linear combination of a normal load and a tangential load. The Fourier transform techniques have been used to find the solution to the problem. The displacement components, stress components, and conductive temperature distribution with the horizontal distance are computed in the transformed domain and further calculated in the physical domain using numerical inversion techniques. The effect of angle of inclination of normal and tangential load for Green Lindsay Model and time-harmonic source for Lord Shulman model is depicted graphically on the resulting quantities.

• 대한기계학회논문집A
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• 제30권11호
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• pp.1384-1391
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• 2006

The problem of an infinite anisotropic material with a crack inclined with respect to the principal material axes is analyzed. The material is subjected to uniform biaxial load along its boundary. It is assumed that the material is homogeneous, but anisotropic. By considering the effect of the horizontal load, the distribution of stresses at the crack tip is analyzed. The problem of predicting critical stress in anisotropic solids which is a subject of considerable practical importance is examined and the effect of load biaxiality is made explicitly. The present results based on the normal stress ratio theory show significant effects of biaxial load, crack inclination angle and fiber orientation on the critical stress. The analysis is performed for a wide range of the crack angles and biaxial loads.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권1호
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• pp.117-135
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• 2016

Performance enhancement is one of the most important issues in high performance distributed computing systems. In such computing systems, online users submit their jobs anytime and anywhere to a set of dynamic resources. Jobs arrival and processes execution times are stochastic. The performance of a distributed computing system can be improved by using an effective load balancing strategy to redistribute the user tasks among computing resources for efficient utilization. This paper presents a multi-class load balancing strategy that balances different classes of user tasks on multiple heterogeneous computing nodes to minimize the per-class mean response time. For a wide range of system parameters, the performance of the proposed multi-class load balancing strategy is compared with that of the random distribution load balancing, and uniform distribution load balancing strategies using simulation. The results show that, the proposed strategy outperforms the other two studied strategies in terms of average task response time, and average computing nodes utilization.

• Structural Engineering and Mechanics
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• 제57권3호
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• pp.543-567
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• 2016

This study attempts to address the buckling and free vibration characteristics of an isotropic cylindrical panel subjected to non-uniform temperature rise using numerical approach. Finite element analysis has been used in the present study. The approach involves three parts, in the first part non-uniform temperature field is obtained using heat transfer analysis, in the second part, the stress field is computed under the thermal load using static condition and, the last part, the buckling and pre-stressed modal analysis are carried out to compute critical buckling temperature as well as natural frequencies and associated mode shapes. In the present study, the effect of non-uniform temperature field, heat sink temperatures and in-plane boundary constraints are considered. The relation between buckling temperature under uniform and non-uniform temperature fields has been established. Results revealed that decrease (Case (ii)) type temperature variation field influences the fundamental buckling mode shape significantly. Further, it is observed that natural frequencies under free vibration state, decreases as temperature increases. However, the reduction is significantly higher for the lowest natural frequency. It is also found that, with an increase in temperature, nodal and anti-nodal positions of free vibration mode shapes is shifting towards the location where the intensity of the heat source is high and structural stiffness is low.

• 한국공간구조학회논문집
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• 제18권2호
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• pp.99-108
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• 2018

This paper presents the design, analysis, and experimental evaluations of precast reinforced UHPC (ultra high-performance concrete) beams with a new design concept of non-uniform flexural members. With outstanding mechanical properties of UHPC which can develop the compressive strength up to 200MPa, the tensile strengths up to 8~20MPa and the tensile strain up to 1~5%, a non-uniform structural shape of UHPC flexural beams were optimally designed using three-dimensional finite element analysis. The experiments were carried out and compared with the design strength in order to verify the performance of them. Proposed non-uniform UHPC beams were evaluated by a series of three-point beam loading test as well as estimated by design bending and shear strength of members. The newly designed UHPC beams show excellent performances not only in transverse load capacities but also in deformation capacities.

• Composites Research
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• 제15권3호
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• pp.11-17
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• 2002

본 연구에서는 분산형 강화복합재료에 균열이 발생하면 하중부하능력이 감소와 더불어 재료의 손상을 초래할 수 있어 재료의 완전한 게재물과 균열이 존재한 게재물이 있는 경우를 상정하여 하중부하능력과 탄성 음력분포를 평가한다. 무한체가 전단음력을 받을 때 완전한 게재물과 균열이 내재한 경우에 대하여 3차원 유한요소해석이 수행되어 완전한 게재물의 경우는 게재물의 영역의 음력은 동일하고 게재물의 계면은 다소 불균일하게 나타났다. 그리고 균열이 내재한 경우에는 균열주변에는 음력이 집중되는 경우를 볼수 있을 뿐만아니라 아주 복잡한 분포를 볼수 있었다. 불균질물의 평균응력은 하중부하능력으로 표현이 가능하였고 완전만 게재물과 균열의 경우도 균열손상에 의해 하중부하능력의 차이를 볼 수 있었다. 특히, 균열이 내재한 경우에 에스펙터비(aspect ratio)가 증가할수록 하중부하능력이 증가함을 알 수 있었다.

• 설비공학논문집
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• 제15권2호
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• pp.95-102
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• 2003

Optimization for the insulation thickness and external shape of a household refrigerator is peformed in order to minimize thermal load through the insulation wall. The one dimensional conduction heat transfer model is adopted to calculate thermal load. Calculus of variation is employed to optimize the thickness and shape of refrigerator or freezer. The uniform distribution of an insulation thickness and cubed external shape make thermal load minimize. Finally, by using both of the computational and experimental method, the thermal load is minimized for a refrigerator/freezer. It is shown that there exists optimal thickness of insulation walls and external shape for given the external cabinet dimensions and freezer and refrigerator internal volumes, Also, the analytical results are well agreed with the experimental results.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
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• pp.297-302
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• 2000

This paper presents the effect of diaphragm spacing ratio(depth to span) on behavior and capacity of composite steel-concrete structures of sandwich system. Numerical analysis has been performed variety diaphragm ratio, behavior and load condition. As a results of this study, in case of shear behavior and concentrated load, the capacity of structure such as yielding and ultimate load improve according to diaphragm ratio because of concrete confining effect by steel plate and stress redistribution by diaphragm. But in case of bending behavior or uniform load, it proved that diaphragm ratio don't influence on behavior and capacity of composite structures of sandwich system.

• 한국철도학회논문집
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• 제9권6호
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• pp.753-760
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• 2006

This paper presents the procedure and results of the numerical modelling that was carried out to investigate the stability of reinforced soil slopes under dynamic railway load. The two-dimensional explicit dynamic finite element method (ABACUS) was used to carry out the numerical analyses. To simulate the railway load, the top surface of the embankment was excited by the uniform distributed load whose frequency and magnitude was estimated by the measured railway acceleration during train passing. The embankment displacements and geogrid axial forces were analyzed to evaluate the stability of reinforced soil slopes under the dynamic train load.

• 한국통신학회논문지
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• 제27권11C호
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• pp.1040-1045
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• 2002

This paper focuses on a hash-based, distributed Wet caching network that eliminates inter-cache communication. An agent program on cache servers, a mapping program on the DNS server, and other components comprised in a distributed Web caching network were modified and developed to implement a so-called "consistent" hashing. Also, a dynamic load balancing algorithm is proposed to address the load-balancing problem that is a key performance issue on distributed architectures. This algorithm effectively balances the load among cache servers by distributing the calculated amount of mapping items that have higher popularity than others. Therefore, this developed network can resolve the imbalanced load that is caused by a variable page popularity, a non-uniform distribution of a hash-based mapping, and a variation of cache servers.