• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.2
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• pp.219-235
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• 2014

With the development of the technology of underwater moving bodies, the need for developing the knowledge of surface effect interaction of free surface and underwater moving bodies is increased. Hence, the two-phase flow is a subject which is interesting for many researchers all around the world. In this paper, the non-linear free surface deformations which occur during the water-exit of a circular cylinder due to its buoyancy are solved using finite volume discretization based code, and using Volume of Fluid (VOF) scheme for solving two phase flow. Dynamic mesh model is used to simulate dynamic motion of the cylinder. In addition, the effect of cylinder mass in presence of an external force is studied. Moreover, the oblique exit and entry of a circular cylinder with two exit angles is simulated. At last, water-exit of a circular cylinder in six degrees of freedom is simulated in 3D using parallel processing. The simulation errors of present work (using VOF method) for maximum velocity and height of a circular cylinder are less than the corresponding errors of level set method reported by previous researchers. Oblique exit shows interesting results; formation of waves caused by exit of the cylinder, wave motion in horizontal direction and the air trapped between the waves are observable. In 3D simulation the visualization of water motion on the top surface of the cylinder and the free surface breaking on the front and back faces of the 3D cylinder at the exit phase are observed which cannot be seen in 2D simulation. Comparing the results, 3D simulation shows better agreement with experimental data, specially in the maximum height position of the cylinder.

• The Journal of Industrial Distribution & Business
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• v.10 no.5
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• pp.59-66
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• 2019

Purpose - Many studies show that dissatisfied customers are silent rather than expressing complaints directly to firms. Although silent voices are pervasive in service failure, they have received little attention from researchers. Silence implies a multidimensional nature, not just the opposite of voice. This study focuses on two types of silent students in higher education: acquiescent silence and defensive silence. This study also proposes cognitive trust and affective trust as variables affecting student silence. The objective of this study is to analyse the effects of trust types on student silence and exit intention. Research design, data, and methodology - To test the proposed model, this study conducted a survey with undergraduate students who selected silence in a dissatisfied relationship with a professor. Respondents were asked to respond to the questionnaire, recalling the dissatisfaction at that time. A total of 300 students was surveyed from whom 275 completed questionnaires was obtained. The structural equation model analysis was used for the hypothesis test. Results - First, cognitive trust was negatively related to acquiescent and defensive silence. Second, affective trust was negatively related to acquiescent and defensive silence. Third, cognitive trust was negatively exit intention, but affective trust didn't significantly reduce exit intention. Forth, acquiescent silence was positively related to exit intention, but defensive silence didn't have a significant positive impact on exit intention. Thus, a key result of this analysis was that acquiescent silence enhances exit intention. Conclusions - The findings of the study provide a better understanding of the types of silence, and the role of trust, thus furthering the implication of student reactions to dissatisfaction. In particular, this study is meaningful in that it confirms the value of student silence in the context of complaint management. Acquiescent silence should be more importantly managed because it has stronger negative motive than defensive silence. Acquiescent silence is reduced through various channels(mail, telephone, counseling) that can express complaints. Cognitive trust and affective trust are a essential factors in reducing silence. Also, in explaining exit intention, cognitive trust plays a more important role than affective trust.

• Journal of Arbitration Studies
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• v.31 no.4
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• pp.99-117
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• 2021

In this study, the effect of reducing and increasing factors in relationship conflict on the relationship exit between auto parts suppliers and buyers was analyzed based on transaction cost theory and relational exchange theory. As a result of the hypothesis test, Hypothesis 1, which states that relationship commitment will hurt relationship exit, and Hypothesis 3 that replacement will harm relationship exit were supported. In addition, Hypothesis 2 which states that transaction-specific investment will positively affect relationship exit was not supported. The theoretical and practical implications of this study are as follows. This study has identified the antecedents of relationship exit by comprehensively applying the transaction cost theory and relational exchange theory. In addition, this study can identify what a company should manage specifically to lower conflict and relationship exit by identifying the antecedents of relationship exit. The limitations of this study and the directions for future studies are as follows. First, not all of the antecedents of relationship exits between auto parts suppliers and buyers have been extensively investigated in the viewpoint of the transaction cost theory and relational exchange theory. In the future, it is necessary to identify additional factors. Second, the study was conducted only from the supplier's viewpoint. In future studies, it is expected that more accurate research results can be obtained by simultaneously examining the supplier's point of view and the buyer's point of view.

• Architectural research
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• v.22 no.2
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• pp.53-61
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• 2020

The purpose of this study is to examine the influence of remoteness between exit stairways on evacuation performance. Firstly, we reviewed the design regulations of the U.S., the U.K., and South Korea, in relation to remoteness between Exit stairways. Secondly, evacuation simulation was implemented, in order to evaluate the adequacy of each standard. Eight tall buildings in South Korea were selected for the simulation. Evacuation performance was assessed for different remote distances between Exit stairways. Lastly, this research analyses the evacuation simulation data statistically in relation to the effect of remoteness on evacuation time. We found that as the distance between two exit stairways increases, the total evacuation time and average evacuation time for evacuees decreases. There was no statistical influence between the maximum travel distance of the evacuee and the remoteness between two exit stairways, but there was a significant effect on the average travel distance of the evacuees. In addition, the results from the optimal point showed that the L_ratio had the highest evacuation time at 0.44, while the D_ratio had the highest evacuation time at 0.38.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1816-1819
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• 2003

As a result of milling operation, we expect to have burr at the outward edge of workpiece. Also, it causes undesirable problems such as deburring cost, low quality of machined surface, and bottleneck in manufacturing process. Though it is impossible to totally remove burr in machining, it is necessary to plan a machining process that minimizes the occurrence of burr. In this paper, a scheme is proposed which identifies the tool path of the milling operation with minimum burr. In the previous research, a Burr Expert System was developed where the feature identification, the cutting condition identification, and the analysis on exit burr formation are the key steps in the program. The Burr Expert System predicts which portion of workpiece would have the exit burr in advance so that we can calculate the burr length of each milling operation. Here, the critical angle determines whether the burr analyzed is an exit burr or not. So the burr minimization scheme becomes to minimize the burr with critical angle. By iterating all the possible tool paths in certain milling operation, we can identify the tool path with minimum burr.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.4
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• pp.93-100
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• 2007

The flow velocity distribution at inlet and exit of Diesel Particulate Filter(DPF) by fabricating L-shape connector with the DPF was measured using a Pitot-tube and 2-D transverse machine. An adaptor designed for making the Pitot tube probe access to the inlet and exit of the DPF was connected with the inlet and exit flange of the DPF, respectively. The Pitot tube which was mounted in the 2-D positioning machine could access to the inlet and exit of the DPF through the rectangular window of the adaptor. The L-shape connector in the DPF inlet has a flow guide which is a perforated steel pipe. The flow velocity distribution at the inlet of the DPF showed a chaotic velocity distribution which is different from that with a diffuser type connector. The velocity distribution at the exit of the DPF showed a crown shape which is similar to that of the diffuser type connector. The velocity distribution at the exit of DPF showed different patterns according to the air flow rate.

• Survey Research
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• v.4 no.2
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• pp.87-102
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• 2003

Till now, much progress has been made in election forecasting. But fixed-line telephone survey has limitations, because it has become more and more difficult to get a representative sample, Exit poll has been considered to provide a new solution. From the beginning, exit poll provided more accurate predictions than those based on surveys using fixed-line phone. In 2002 presidential election, prediction based on exit poll was perfect. Its predictive error was zero. This paper describes how the exit poll was done in 2002 presidential elections. Specifically, we are to show the estimating procedures as well as sampling and polling process. Among many factors, sampling procedure has been fond to be the most important factor in exit poll accuracy.

• Fire Science and Engineering
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• v.33 no.6
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• pp.28-34
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• 2019

The purpose of this study is to examine the influence of occupant's path selection on the shape of the pictogram and the opening/closing of the door. This study was carried out through a simulation experiment using computer virtual reality. Exit light pictogram for exit door and exit light pictogram for passage were arranged for each scenario in type T corridor and type + corridor. The computer graphic was used to carry out the simulation. In addition, we analyzed the response of human behavior according to the two directions (left and right) of exit light pictogram for exit door and the effect of opening direction of doorway. In addition, the change of decision-making according to the presence or absence of exit light pictogram for passage was confirmed. The results of the direction selection response were as follows. First, in the case of the T-shaped corridor, if the exit light was not installed on the door, it was influenced by the opening direction of the door. Second, when the exit light is attached to the door, the selectivity in the direction that matches the exit light pictogram direction is high. As a result, it was confirmed that the pictogram direction of the exit light influenced the evacuation route selection of the occupants.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.1049-1050
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• 2006

In this paper, we present the analysis of Tree-LDPC codes using EXIT(Extrinsic information transfer) charts methods. Two different EXIT charts schemes are compared. One is based on the closed form equation and the other is based on Monte-Carlo simulation. The thresholds by these two schemes match well with the threshold by DE(density evolution) scheme. Simulation performance is also shown with the obtained thresholds.

• Tunnel and Underground Space
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• v.6 no.3
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• pp.245-249
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• 1996

In this study, the flow field and the recirculation phenomena are investigated numerically for the model around a tunnel entrance and exit. It turns out that the air entering to the tunnel entrance comes mostly from the upper region of the entrance implying that maintaining the air clear in that region is important for the inside-tunnel ventilation. We also found that the recirculation of the exhaust gas from the exit to the entrance has a maximum effect when the flow velocity at the exit is somewhat lower than that of the entrance.