• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.378-384
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• 2008

This Paper presents dynamic analysis of HVAC(Heating Ventilation & Air Condition) Heater Case which consists of heater and evaporator unit for passenger car. To analyze the dynamic characteristics of HVAC Heater Case. finite element model which consists of shell elements is constructed for modal analysis and experimental Modal analysis has been conducted. Finite element analysis results are compared with experimental results to evaluate of validity of finite element model After identifying node shape and natural frequency of HVAC Heater Case, local stiffness of HVAC Case is evaluated through point mobility using finite element analysis and experiment.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.265-268
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• 2006

Performed fatigue strength analysis for Hub to get the targeted service life of 20 years. ANSYS is used to analysis. The major structure of bearing which connect the hub and blades is modeled using the element of LINK10. To represent the stiffness of LINK10 element, initial strain and diameter of LINK10 element is applied. Prior to calculating the fatigue damages, the influence matrix is extracted from the unit loads. The target service life of 20 years is achieved from the Analysis results.

• Structural Engineering and Mechanics
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• v.20 no.3
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• pp.279-292
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• 2005

In this study, element loading matrices are defined for static application of classical M$\ddot{u}$ller-Breslau principle to finite element method. The loading matrices are derived from existing element matrices using Betti's law and known governing equations of F.E.M. Thus, the ordinates of influence lines and influence surfaces may be easily obtained from structural analysis for the loading matrices derived from governing equations, instead of through introduced unit force or displacement techniques. An algorithm for a computer program and comparative numerical examples are also presented to illustrate the procedure for determination of influence line and surface ordinates.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.1
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• pp.101-108
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• 2009

This paper presents dynamic analysis of HVAC(heating ventilation & air conditioning) heater case which consists of heater and evaporator unit for passenger car. To analyze the dynamic characteristics of HVAC heater case, finite element model which consists of shell elements is constructed for modal analysis and experimental modal analysis has been conducted. Finite element analysis results are compared with experimental results to evaluate of validity of finite element model. After identifying mode shape and natural frequency of HVAC heater case, local stiffness of HVAC case is evaluated through point mobility using finite element analysis and experiment.

• Journal of Ocean Engineering and Technology
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• v.27 no.2
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• pp.13-18
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• 2013

Most ships and offshore structures are equipped with a variety of pipes, which inevitably contain curved portions. The structural design of these pipes mostly relies on the commercial code, CAESAR-II, which was especially developed for the structural analysis of pipes. This study conducted stress analyses of the same pipe unit, including loops, using both CAESAR-II and MSC/NASTRAN, and compared the results to investigate the characteristics of CAESAR-II. A parametric study was then conducted of the various design variables of pipe loops using CAESAR-II to draw some useful information about the structural characteristics of the loops.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1085-1090
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• 2011

To assure the safety of rolling stock, it is important to perform the fatigue analysis of reduction gear unit in rolling stock considering a variation of velocity and traction motor capability. This paper presents fatigue analysis of the damage of reduction gear unit of railway vehicle under variable amplitude loading(VAL) based on quasi-static fatigue analysis using finite element model and linear Miner's rule. The VAL for the simulation was constructed from the tractive effort curve and train run curves of railway vehicle under commercial operation condition using MSC.ADAMS dynamic analysis. The finite element model for evaluating the carburizing effect on the gear surface was used for predicting the fatigue life of the middle gear based on strain-life based approach. The results showed that the frequent high starting torque due to a quick start as well as increasing numbers of stops at station would decrease the fatigue life of reduction gear unit.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.4
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• pp.313-326
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• 2007

With rising prevalency of mouth breathing children caused by developing civilization and increasing pollution, there are many maxillary transverse discrepancy patients with undergrowth of maxilla. For improving this, maxillary mid-palatal suture splitting was often performed. The purpose of this study was to analyse the stress distribution on the craniofacial suture and cranium after rapid maxillary expansion by finite element model. The boy(13Y6M) was chosen for taking computed-tomography for finite element model. Three-dimensional model of maxilla, first premolar, first molar, buccal and lingual part of rapid maxillary expansion were constructed. 1. The alveolar bone adjacent to the first molar and the first premolar that was affected directly by rapid maxillary expansion was displaced laterally approximately 4.04mm at maximum. The force decreased toward anterior region and frontal alveolar bone displaced laterally about 3.18mm. 2. A forward maximum displacement was exhibited at zygomatic process middle region. 3. At maximum, maxillary median part experienced 0.973mm downward repositioning and 0.65mm upward repositioning at lateral alveolar bone. 4. Von mises stress was observed the largest stress distribution around teeth and zygomatic buttress. 5. The largest tensile force was observed around alveolar bone of teeth, while compression force was observed at zygomatic buttress.

• Journal of the Korean housing association
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• v.16 no.2
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• pp.55-65
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• 2005

'Movement System' is made of the interaction of user and architectural spaces related to each other in order. 'Movement' meant in movement system is possible only in the status of user and architectural space together. Movement created and disappeared by the user is not subordinated to the existing architectural space but becomes the main element of formating movement system. It is required that movement conception applied to architecture should be derived from the essence of movement and this study presents the movement system. To explain the formating process of movement system, A. N. Whitehead's process philosophy theory is at the basis and transformed in architectural aspects. On basis of these theoretical backgrounds, the process of making movement system can be explained. There are unit movement, unit object, and elements for movement process as the basic requirements for movement system, each unit is apprehended by individual operation and the nexus is composed by associative operation of apprehended units. This nexus becomes the object of a new subject and forms multiple nexus. Relation of unit movement and unit object and nexus are apprehended as the continuation and extensive continuum is made. At that time, movement with multiple phases set inbetween systems and extended multiplied. Through above study, movement system is applied to Korean traditional houses.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.6
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• pp.499-505
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• 2011

This paper presents optimal design of controllable magnetorheological suspension unit for a tracked vehicle. As a first step, a double-rod type MR suspension unit is designed on the basis of the Bingham model of commercially available MR fluid, and its damping characteristics are evaluated with respect to the intensity of the magnetic field. Subsequently, the governing equation of motion of the MR suspension system featuring the MR valve is established. Then, the optimization problem to find optimal geometric dimensions of the MR supension unit is formulated by considering an objective function which is related to damping torque and control energy. The first order optimization method intergrated with a commercial finite element method(FEM) software is adopted to obtain optimal solution of the system. The performance characteristics of the optimized MR susepnsion unit is then evaluated and compared with initial one.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.6
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• pp.512-519
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• 2016

Auxiliary Power Unit of FA-50 which provides energy other than propulsion is an important element to maintain airworthiness on aircraft. Also Inlet Guide Vane of Auxiliary Power Unit is a device that supplies appropriate airflow into the Auxiliary Power Unit after adjusting influent airflow into the load compressor. This report, based on the problems occurred the driving gears of Inlet Guide Vane, deals with cause of occurrence, troubleshooting, design improvement and result of test flight verification for FA-50 aircraft Auxiliary Power Unit lifespan.