• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.4
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• pp.428-435
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• 2015

This paper presents the experimental study of cabin thermal comfort using a cold storage heat exchanger in a vehicle air-conditioning system. Recent vehicle-applied ISG functions for fuel economy and emission, but when vehicles stop, compressors in the air-conditioning system stop, and the cabin temperature sharply increases, making passengers feel thermal discomfort. This study conducts thermal comfort evaluation in the vehicle, which is applied to a cold storage system for the climate control wind tunnel test and the vehicle fleet road test with various airflow volume rates and ambient temperatures blowing to the cold storage heat exchanger. The experimental results, in the cold storage system, air discharge temperature is $3.1-4.2^{\circ}C$ lower than current air-conditioning system when the compressor stops and provides cold air for at least 38 extra seconds. In addition, the blowing airflow volume to the cold storage heat exchanger with various ambient temperature was examined for the control logic of the cold storage system, and in the results, the airflow volume rate is dominant over the outside temperature. For this study, a cold storage system is economically useful to keep the cabin at a thermally comfortable level during the short period when the engine stops in ISG vehicles.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.5
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• pp.77-83
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• 2008

Semi-active cabin air suspension system improves driver's comfort by controlling the damping characteristics in accordance with driving situation. For the driver's comfort evaluation, test procedure has the two methodologies which are filed test and lab test. A field test method has a drawback. It requires a lot of time and money on repetitive test, due to the sensitivity of field test. On the other hand, the test with six axes simulation table at laboratory can obtain the repeatability of test, better than the field test method. In this paper, the procedures of ride performance test and control logic tuning with the table are presented. Drive files of the table can be represented with the almost same input condition as field test data. According to the result from the comparative test using six axes simulation table between passive and semi-active system by making ECU logic tuning, the RMS acceleration of semi-active cabin air suspension system was reduced by 29.6% compared with passive system.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.3
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• pp.255-264
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• 2015

Wind load and flow field of a drillship with respect to various super structures were experimentally investigated in KARI 1m-wide wind tunnel with an atmospheric boundary layer simulation. Six-component external balance and Particle image velocimetry technique were used to measure wind load and velocity vectors in the flow-field around the model respectively. The experimental model was an imaginary shaped drillship with an approximated model which has 1/640 scale compared with recent typical drillships. The test Reynolds number based on the overall length was about 1.5×10⁶. It was found that dominant factors influencing on ship wind load are cabin shape and cabin height. Round cabin has smaller axial wind load and narrow boundary layer around the ship than rectangular one, but its yawing moment at certain angles becomes higher. Low cabin height also show positive effects on axial wind load too. Hull shape and forecastle shape show relatively small influences on wind loads except for slight changes around ±45° wind directions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7377-7384
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• 2015

Agricultural tractors must have a function of ROPS to protect drivers under roll-over accident. In this study, finite element analyses and an optimal design were performed to reduce the cost and the production period of the cabin frame of a tractor to pass the ROPS strength test. To confirm the pass of ROPS strength test of an initial design model, the results of deformation and principal strain from the analyses were evaluated. To reduce the weight of the cabin frame, design of experiment of Taguchi was implemented, and an optimal design was obtained. The weight of the optimal design model was reduced by 7% comparing with the initial design model.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.6
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• pp.29-37
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• 1994

Active noise control of random noise which propatate in the vehicle cabin as a form of spherical wave is the target of this study. In the previous study, the adaptive algorithm for adaptive controller is presented for the application in active noise control system. And for the preliminary study of adaptive active noise control in vehicle cabin as a real system, a computer simulation is performed on the effectiveness of the adaptive algorithm in the amplitude of the pressure fluctuation. This work studies the implementation of multi-channel feedforward adaptive algorithm for the reduction of the noise inside a vehicle cabin using a number of secondary sources derived by adaptive filtering of reference noise source. Multi-channel adaptive feedforward algorithm are verified in numerical simulation and semi-experimental justification of developed system is made on a domestic passenger car. In the results of semi-experimental study, the noise of specific region in the interior of automobile are reduced for the appreciabe sound pressure level in the operating engine rpm and finally this study suggests the capabilities of the real time active noise control in 3 dimensional acoustic fields.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.3
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• pp.76-89
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• 2012

The number of foreign cabin crews consist of 7% of total crews in K-airline, of which Chinese crews are of 38%. The number of foreign crews are 433 from 10 countries as of the end of July 2012. The airline has continued to hire foreign cabin crews to increase efficiency of human resourcing qualified flight attendants. This paper tried to do empirical research through SEM(Structural Equation Model) to overview confirmatory factors and course effects integrally. Cultural stress, aggressive coping, social support and job adaption have been chosen to be a factors. Especially, the SEM was set to show indirect effects of cultural stress and aggressive coping through social support to the dependant variable, job adaptation. According to the analysis result, cultural stress has a direct negative effect on job adaptation. Aggressive coping has also a direct positive effect on job adaptation. It has also proven cultural stress and aggressive coping has a indirect effect to job adaptation through social support. This paper is expect to contribute to develop such training and administrative programs as enhancing foreign crews' job adaptability and managing them effectively.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.27 no.3
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• pp.54-69
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• 2019

Transformational and authentic leadership are known to create positive effects on follower's various outcomes, like job satisfaction and organizational commitment. We're mostly interested in testing positive effects of transformational and authentic leadership of cabin team leaders in airline industry, because their leadership tends to have strong and immediate impact on cabin crew's quality of customer services. We figured that cabin team leader's transformational and authentic leadership had positive effects on crew member's job satisfaction and organizational commitment. And, these positive relationships were at least partially mediated through crew member's self-efficacy and LMX. Based on these positive results, we discussed several theoretical and practical implications for developing effective leadership across cabin team leaders in airline services industry.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.657-663
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• 2018

In this study, shape optimization was performed to improve the vibration isolation capability of an anti-vibration rubber assembly, which is used in the field option cabin of agricultural tractors. A uniaxial tension test and biaxial tension test were performed to characterize the hyper-elastic material properties of rubber, and the data were used to calibrate the material model used in the finite element analyses. A field test was performed to quantify the input excitation from the tractor and the output response at the cabin frame. To account for the nonlinear behavior of rubber, static analyses were performed and the load-displacement curve of rubber was derived. The stiffness of the rubber was calculated from this curve and input to the harmonic analyses of the cabin. The results were verified using the test data. Taguchi's parameter design method was used to find the optimal shape of the anti-vibration rubber assembly, which indicated a shape with reduced stiffness. The vibration of the cabin frame was reduced by the optimization by as much as 35% compared to the initial design.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.2
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• pp.85-91
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• 2016

The Positive Temperature Coefficient (PTC) is used for cabin air heating of a battery electric vehicle, which is different from conventional vehicles. Since the PTC heater consumes a large quantity of power in a parasitic manner, many valuable studies have been reported in the field of alternative heat pumps. In this study, a model for an R134a heat pump taking into account the thermal environment of the cabin was developed for a MATLAB/SIMULINK(R) platform. Component and cabin models are validated with reference values. Results show that the heat pump is more competitive for parasitic power consumption over all ambient temperature conditions. Additionally, the method of waste heat recovery to overcome disadvantages when temperatures are below zero is applied to efficiently operate the heat pump.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.5
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• pp.145-157
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• 2018

The purpose of this study is to explore ways of service recovery and procedures through the service failure cases depending on the employee capacity that leads to improving quality of the airline cabin service. This study was tested using the failure case of airline in korea. Since interrupting and discontinuing of customer service affect customer defections, customer satisfaction must quickly respond to the service's error situation. The service of the cabin crew is closely related to the customer's evaluation, the direct connection. Customer's objectives are to meet employee needs for service recovery and to recognize and analyze customer perceptions of human resources services, restore customer expectations and maintain contracts with customers. Therefore, this study proposes a set of strategies for effectively preventing and responding to customer related service failure in the airline cabin service.