• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.11a
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• pp.383-384
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• 2022

Gas Combustion Unit (GCU) onboard liquefied natural gas carriers handles boil-off to stabilize tank pressure. There are many factors for LNG cargo operators to take into consideration to determine whether to use GCU or not. Gas consumption of main engine and re-liquefied gas through the Partial Re-Liquefaction System (PRS) are good examples of these factors. Human gas operators have decided the operation so far. In this paper, some deep learning neural network models were developed to provide human gas operators with a decision support system. The models consider various factors specially into GCU operation. A deep learning model with Sigmoid activation functions in input layer and hidden layers made the best performance among eight different deep learning models.

• Journal of Advanced Navigation Technology
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• v.20 no.6
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• pp.544-555
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• 2016

Organizations of airport continue to invest heavily in the acquisition of self-esteem. Because, it is that self-esteem will become more productive. In this article, We verify to influence in the operation performance by the air navigation system and moderated effect of self-esteem. A survey of Incheon International Airport and Gimpo International Airport was conducted to better understand the factors that affect air navigation system to explain operation performance of airport perspective on air navigation system operator. The findings indicate that the positively moderated self-esteem affects operation performance of airports. We also confirmed that air navigation policy, maintenance, and promotion activities of air navigation system factors are affecting the operation performance of airports. The results of this study suggest that self-esteem could be the basis for a strong measurement tool to evaluate whether self-esteem in a given organization of airport are meeting enhancement of operation performance.

• Journal of Nutrition and Health
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• v.37 no.5
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• pp.406-414
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• 2004

The purposes of this study were 1) to investigate the importance level on factors affecting the foodservice management contract perceived by the clients in the office building, government and public offices and manufacturing company in Seoul and Kyungi 2) to compare the perceived importance levels of the present contract and future contract 3) to compare the perceived importance levels of the competitive bid with those of the private contract. To collect the data on the perceived importance level on the affecting the foodservice management contract, the questionnaires were developed by the delphi technique and modified by the pilot test. The questionnaires consisted of 4 categories and 19 items on the factors affecting the foodservice management contract and the importance level on the factors were measured by 5-likert scale. From March 12 to April 13 in 2003, the self-administrative questionnaires were mailed to 280 clients. The questionnaires were responded from the 50 clients (respondent rate: 25％). On the factors affecting the present contract and the future contract, among the 4 categories (the appropriateness of foodservice operation plan, the evaluation of the foodservice company, sales ability, the conditions of the cost in the contract), the importance level of the appropriateness of foodservice operation plan was higher than those of the other categories. In the comparison of the perceived importance level between the present contract and the future contract, the importance level of 4 items (sanitation and safety management plan, menu management plan, service management plan, food cost per meal) in the future contract were significantly higher than those in the present contract (p＜.01, p＜.05, p＜.05, p＜.01). There were the significant differences between the private contract and competitive bid on the factors affecting the present contract in the 3 items, which were $\ulcorner$renewal plan for interior and environment$\lrcorner$, $\ulcorner$strategic alliance with the contractor$\lrcorner$, $\ulcorner$lobby of the foodservice company$\lrcorner$ (p＜.05, p＜.05, p＜.05). And on the factors affecting the future contract, there were significant differences in the 2 items, which were $\ulcorner$renewal plan for interior and environment$\lrcorner$and $\ulcorner$cost per meal$\lrcorner$in comparing the competitive bid and private contract (p＜.05, p＜.01). The clients perceived the appropriateness of foodservice operation plan was more important than the other categories in the future foodservice management contract. It was proposed that the foodservice management contract company should focus on the foodservice operation to satisfy the customers and clients in order to get more contract in the future.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.4
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• pp.1-10
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• 2020

Safety can be defined as being maintained or reduced to a level below which the possibility of human or physical harm can be tolerated through continuous identification of risks and safety risk management. FAA, EASA, IATA and Boeing, major organizations that conduct research and analysis for aviation safety around the world, report that about 70 percent of aviation accidents are caused by human factors, which have led to a surge in interest in human factors-induced accident prevention activities around the world. As part of this purpose, the FAA in the U.S. is raising awareness among aviation workers by publicizing the 12 human errors (Boeing, 2016), which account for the largest part of aviation accidents under the theme of Dirty Dozen, to prevent aviation accidents. Therefore, based on the domestic helicopter accidents reported to the Air Railroad Accident Investigation Committee from 2007 until recently, this study aims to use HFACS to extract human factors for the six recent helicopter accidents in Korea, analyze the extracted human factors in conjunction with the Dirty Dozen concept, and then present measures to prevent accidents by item.

• International Journal of Automotive Technology
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• v.7 no.5
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• pp.625-635
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• 2006

From a viewpoint of human factors, automated highway systems(AHS) can be defined as one of the newly developing human-machine systems that consist of humans(drivers and operators), machines(vehicles and facilities), and environments(roads and roadside environments). AHS will require a changed vehicle control process and driver-vehicle interface(DVI) comparing with conventional driving. This study introduces a fixed-based AHS simulator and provides questionnaire-based human factors evaluation results after three kinds of automated driving speed experiences in terms of road configuration, operation policies, information devices, and overall AHS use. In the simulator, the "shared space-at-grade" concept-based road configuration was virtually implemented on a portion of the Kyungbu highway in Korea, and heads-up display(HUD), AHS information display, and variable message signs(VMS) were installed for appropriate AHS DVI implementation. As the results, the subjects expressed positive opinions on the implemented road configuration, operation policies, and the overall use of AHS. The results of this study would be helpful in developing the road configuration and DVI design guideline as the basic human factors research for the future implementation of AHS.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1063-1066
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• 1999

This paper presents an extended integral control with the PID controller by introducing the delay and decaying factors. The convolution integral control scheme is developed by substituting proportional convolution integral controls for the proportional-integral control. So far, the integral part of the PI controller produces a signal that is proportional to the time integral of the input of the controller. The steady-state operation points are affected forever by the errors in the past due to the input signal containing the information of the errors in the past. These phenomina may cause some disturbances for other control purposes related to the given PI control. Introduction of forgetting factors of the error in the past can resolve the disturbance problems. Various forgetting factors are developed using the delay, the decaying factors, and the combination of the delay and the decaying factors. The proposed various extended integral control schemes can be applicable to corresponding PI control designs in which the error in the past may badly affect to the current steady-state operation points and may cause some disturbances for other control purposes.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.7
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• pp.345-349
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• 2000

This paper presents an extended integral control with the PI controller by introducing the delay and decaying factors. The extended integral control scheme is developed by substituting the proportional convolution integral control for the PI(Proportional Integral) control. So far, the integral part of PI controller produces a signal that is proportional to the time integral of the input signal to the controller. The steady-state operation points are affected forever by errors in the past due to the input signal containing the information of the error in the past. These phenomena may cause some disturbances for other control purposes related to the given PI control. Introduction of forgetting factors to the error in the past can resolve the disturbance problems. Various forgetting factors are developed using the delay elements, the decaying factors, and the combination of the delay and decaying factors. The proposed various extended integral control schemes can be applicable to the corresponding PI control designs in which the error in the past may badly affect the current steady-state operation points and may cause some disturbances for other control purposes.

• Clinics in Shoulder and Elbow
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• v.9 no.1
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• pp.27-33
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• 2006

Purpose: To investigate early complications after repair of massive rotator cuff tears and to find out factors that compromise the results. Materials and Methods: Fourteen patients who had two or more cuff tendons involved were included. All patients were operated by open acromioplasty and rotator cuff repair. At 3 months after operation, we investigated whether there were any early complications or not. We used ASES scoring system for preoperative and follow up evaluation. In addition, various preoperative factors, such as duration of symptom, degree of tendon retraction, degree of fatty degeneration, and acromio-humeral distance, were compared between the complicated patients and non-complicated patients. Results: At 3 months after operation, the ASES score and pain were improved in any degree in all patients. But 5 patients complained persisting pain, and three of them showed major complications such as re-rupture of rotator cuff or deltoid rupture. But no preoperative factors in complicated patients were significantly different from those in non-complicated patients. Conclusion: None of the preoperative factors were related to the complications. There was a tendency of overestimation of fatty degeneration in MRI. Some factors in surgical technique and rehabilitation were highly suspected to be related to the complications.

• Journal of Navigation and Port Research
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• v.31 no.4
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• pp.281-287
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• 2007

Human factors have been considered the primary reason of marine accidents. Especially, the collision between vessels is mostly mused by human behavior. However, there have not been many researches to clarify the reason of marine accidents mused by human factors quantitatively. In order to understand human factors and to enhance safe navigation systematically, using a full mission ship-handling simulator, we've investigated the characteristics of avoiding behavior taken by mariners. Further in order to apply the characteristics more widely and effectively, it's necessary to formulate the standard behavior for ship-handling in the condition of collision avoidance. Is this study, therefore, we intended to propose the concept to model the mariner's standard behavior on the handling of collision avoidance as the first step. As a result, we confirmed the contents of information processing in ship-handling that mariner's generally taking to avoid collision.

• Journal of Navigation and Port Research
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• v.31 no.4
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• pp.309-315
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• 2007

We've investigated the characteristics on mariner's behavior in the collision situation through a full-mission ship handling simulator and considered that it's necessary to model the standard avoiding behavior of mariners in order to apply the obtained results more widely and effectively. Thus we described the contents of standard avoiding behavior taken by mariners in the collision situation and established the concept of the standard model based on human factors for collision avoidance in a previous study. As a following study, this paper is to propose the method of modeling on mariners' standard behavior for collision avoidance by analyzing the contents of mariner's information processing and the related factors using regression analysis. As a result, we confirmed the influence of relating factors to avoiding behavior in mariner's deciding decisions and proposed the modeling method of mariners' standard behavior for collision avoidance with a example of recognition model.