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3.2 Assessment of Mariner's Competency
 
 Assessments of mariner's competency are executed based on mariner's reaction for specific situation. As mentioned before, the required behavior should be clarified for specific situation. In order to assess the specific competency, the situation that connects to the specific behavior corresponding to required competency shall be reappeared. There are three important factors to assess the competency of mariner using simulator.
 
(1) Required behavior should be clarified for specific situation.
(2) Required behavior should be assessed based on rational method.
(3) Simulator using for assessment of competency shall equip the relating function.
 
 For assessing mariner's competency, the functions being reappeared in simulator have to be discussed. That is basically same relation between training technique and necessary simulator's function. Adding to the function in simulator for training, the equipment that supply the information of mariner's behavior are required for the simulator for assessment. The represent installation is monitoring system, which shows his behavior and manipulation of navigational equipments. Photo 7 shows monitoring system for assessing mariner's behavior. Assessor can recognize their action and conversation. The handling contents, ship's motion and traffic condition are also monitored by other system.
 
 The assessment using simulator is applied for judgment of license in some countries. Simulator will be used more and more for assessing mariner's competency to be realized in next generation.
 
Photo.7  
Monitoring display for assessment of mariner's competency
 
4. APPLICATION OF SIMULATOR FOR ASSESSMENT ON NAVIGATIONAL CONDITION
 One of major application of simulator is assessment of navigational condition. The targets of assessment are very large fields mentioned below. There are several kinds of methods to assess the condition. We have to consider the reason why simulator is used for assessment of them. And we have to apply the simulator for assessment after understanding the reasons. Simulator function is very important when we apply the simulator for assessment. We have to clarify the relation between the function of simulator and object of usage
 In this section, the kinds of usage of simulator and discussion on their rationality are shown. The examples of assessments applied simulator are as following,
 
1. Fairway design
2. Harbor design
3, Ship maneuverability
4. Navigation support system
5. Marine traffic
6. Others
 
 The assessment objects mentioned above are not evaluated as only each issue. The subject of each assessing issue is to evaluate the object in the relation to navigational condition. They are assessed whether they affect on the rationality in given condition for safe navigation. The following are the some example of relation between assessment object and other navigational condition.
 
1. Object is assessment on ship maneuverability; navigational condition is shape of fairway.
2. Object is assessment on effectiveness of IBS; navigational condition is specific traffic condition.
3. Object is assessment on shape of fairway; navigational condition is specific traffic condition.
4. Object is assessment on traffic control; navigational condition is specific traffic condition.
5. Others
 
 In the case of assessment, simulator has to fulfill the function of reappearance on the situation in which the assessment object and navigational condition appear. In case I mentioned above, the accurate reappearance of maneuverability is needed and the visual information showing shape of fairway is also necessary. In case 2, the reappearance of traffic condition by visual information is necessary as well as IBS installation. When the assessment is carried out, we have to keep that in mind the function of simulator decides the results of assessment.
 
4.1 Peculiarity of Simulator as a Tool of Assessment
 
 In previous section, it is pointed out that all of assessments are carried out to discuss the relation between the assessing item and the navigational condition. Assessing items may be physical issues or one kind of rule decided by authority. On the other hand, the condition relating to assessing items may be also physical issues. If all of these factors can be expressed by the characteristics as numerical formula and/or some function rule base, numerical simulation can be applied.
 
 When we discuss and evaluate the navigational condition, we have to consider one important factor that give the extreme influence on safe navigation. That is a human factor. The navigation is extremely affected on by operator's behavior. In case of the discussion of safe navigation applying numerical simulation, human factor have to be expressed as some rule. As a result, in order to carry out the assessment on navigational condition applied by numerical simulation, following issues must be satisfied.
 
1. All functions are described in formula or rule base.
2. Human factor is also described in formula or rule base.
 
 When the condition mentioned above is satisfied, numerical simulation can evaluate the relation among the relating factors that can be simulated in specific characteristics.
 
 On the contrary, the region of human factor described in formula or rule base is still small in maritime field. Mariner usually faces many situations and acts many kinds of behaviors. The situations have not been categorized systematically or concretely. Also the studies on mariner's behavior have been done in very small. These are the reasons why mariner's characteristics reacting for many situations have not been clarified.
 
 When we have to assess the navigational condition without knowledge on human factor relating to assessing item, the results of assessment can be used in limited condition. Therefore we have to know the human behavior in given condition in order to assess the condition. When assessment applying simulator is carried out, the objects of simulator experiments are summarized as following,
 
1. To assess the assessing factors directly.
2. To know the human factor in given condition.
 
 In case of #1, in order to get universal assessment on target factors, many experimental cases have to be carried out because, there are lots of relating factors and variable condition in which mariner behaves the wide variation corresponding to the condition. When we decide the assessment with small number of experiments, we can only have restricted solution under the condition. Nevertheless, the results of assessment are often applied for wide condition beyond the prerequisite condition. It is very dangerous for common society as well as mariners. The results of assessment cannot guarantee the safe navigation. In this case, we have to use the results within prerequisite condition.
 
 In case of #2, it is a best way to study the human factor in all of the condition concerned. To know the human characteristics in the condition allow the assessment of items under the condition concerned. In order to know the human characteristics in the condition, we have to discuss the construction of target condition and human's position under the condition prior to simulator experiments. Clarifying the target condition relating to assessment, necessary experiments will be limited numbers. However, most of assessments are carried out by case #1. It is mainly because of limited time, lack of analyzing procedure and lack of thought on this issue.
 
 Meanwhile, to know the human factor is important issue when assessments are carried out using simulator. Therefore, human factor in the condition should be discussed in the process of assessment using simulator. When we carry out the assessment applying simulator, we have to keep the human factor in mind. The meaning of simulator application is to be capable to discuss the human factor.
 
4.2 Study on Human Factor
 
 Human factor is very important factor in the discussion of safe navigation. However, the research results of human factor are extremely small. The researches were mainly discussed in the process of the assessment of physical issues. The physical issues mean navigational issues except human such as ship's characteristics, shape of waterway, instruments and so on. The researches on human factor were not done as direct objectives or systematically. The assessments on all of physical issues will be more efficiently after the systematic researches on human factor will be executed.
 
Examples of study on human factor concerning to ship operation.
 
(1) Study on human characteristics of course keeping and position control.
(2) Study on human characteristics of collision avoiding maneuver.
(3) Study on human characteristics of berthing maneuver.
 
 The studies mentioned above were carried out in the assessment on ship maneuverability or other navigational issues.[8] Some of them are shown in following section relating to the assessment of physical issues.
 
4.3 Study on Characteristics of Ship
 
 Ship maneuvering characteristics are important factor to achieve safe navigation. IMO declare to keep standard maneuvering characteristics to realize safe navigation. Ship motion is not decided only by ship maneuvering characteristics but also by handling characteristics of mariner. In order to maintain the safe navigation, we have to consider the ship's motion handled by human. Before understanding human characteristics for handling ship in specific condition, it is needed to evaluate the characteristics of ship motion controlled by human using simulator. Ship handling simulator is applied for studying this objectives.
 
 Following are some examples of the evaluation of Ship maneuverability.
 
(1) Course keeping ability
 This study can be done using single task simulator without visual scene. The results on this study are applied for the establishment of maneuvering standard of IMO. The reference in the last part of this paper is shown.[9]
 
(2) Position control ability
 This study can be done using multi task simulator with visual scene. Position control is required when navigating restricted water area. Mariner handles the ship over observing buoy or other navigation support arrangement. For this study, the simulator having the function of reappearance of visual images is required. However, the function is allowed within simple image. The reference in the last part of this paper is shown.[10]
 
(3) Berthing ability
 This study can be done using full mission simulator. Bare hull, controlling power equipped in ship and supporting power outside like tugboat are objects of discussion in this subject. Mariner handles her over observing visual objects as important information. Usually, many objects in wide field have to be reappeared precisely as the visual information.
 
(4) Maneuverability in restricted condition
 The present assessments on ship maneuverability have been done for basic conditions. For improving safe navigation, maneuverability in restricted condition has to be enhanced. The following characteristics are items for discussion.
- The characteristics on acceleration and deceleration
- The characteristics under wind and/or singular current condition
- The characteristics on interaction toward other vessel and structure
- Other important issues on safe navigation
 
 The required function of simulator is depends on the contents of study.
 
4.4 Study on Traffic Condition
 
4.4.1 Issues of maritime traffic
 
(1) Risk of collision
 When we discuss the encountering times of traffic vessels in specific water area, we do not need to use ship-handling simulator. Applying numerical simulation can solve it. However when we estimate the difficulty of avoiding collision. we have to use simulator because, the difficulty depends on the way to avoid collision, Mariner decides the way. Mariner's behavior should be clarified to discuss the risk of collision. We have to estimate the reasons of the way through the experiments using simulator. The required function of simulator is depends on the contents of study.
 
4.4.2 Study on Rule of Road
 
(1) Effect of traffic control
 The traffic control is defined as the standardization on natural traffic flow. some methods of standardization are as following,
- COLREG
- Definition of fairway
- Traffic management
 
 Concerning traffic control, ship maneuverability is often pointed out as the objectives of evaluation in order to discuss the rationality of the present or the assumed traffic control It is important issues whether ship handling is capable of the target traffic control. This issue contains two factors, one is ship maneuverability and the other is a human handling characteristics. The issues proposed by the authorities become evaluation items based on ship-human system. In this case, many functions of simulator are required almost same as full mission simulator. However, some of them can be executed by using limited task simulator. For instance, when limited horizontal view without traffic vessel is needed to evaluate narrow fairway, small simulator can be used for them. The required function of applied simulator depends on the issues of evaluation. Necessary function should be discusses carefully. It is important what is object to evaluate the condition and the factors concerned.
 
(2) Buoy arrangement and Condition of light of buoy
 When the buoy is arranged to indicate the navigational condition such as waterway, dangerous point, navigational area and objectives of navigation, suitable buoy arrangement and type of light are discussed. In this case, visual information of simulator is important factor. The visibility and brightness become important for recognition of buoy. These items are to be evaluated. The characteristics of images on Rader/ARPA are also important issues from viewpoint of visual information.
 
4.5 Study on Waterway and Harbor Condition
 
 Geographical condition of waterway and harbor are often discussed as the target of assessment.[11] Shape of waterway, shape of jetties, current condition and wind condition are often discussed for evaluation on the design on them. The reappearance of ship maneuverability and visual information in simulator and human handling characteristics are important factors to evaluate them. In case of study on Fairway, to realize the real situation for evaluating the condition, the information for mariner is necessary. Main functions required in simulator are listed in Table #2. Full mission simulator is mainly used for this issue.
 
4.6 Study on Navigational Equipment
 
 Recently, many kinds of navigational equipment are developed to enhance the safe navigation. However sometime the relation between the functions of equipment and the effectiveness for safe navigation has not been clarified.[12] Basically, these relations should be studied before manufacturing and installing them. When the information to mariner became large, he cannot only use them effectively but he also confuses to process them. Too much information is often to make trouble.
 
 In present situation on navigational equipment, many kinds of equipments are installed onboard. Some of them have installed from 100 years ago and some one has just equipped in these days. During this 100 or 150 years, conventional equipments have been used when new one is equipped. As a result, different navigational equipments supply similar information. Mariner has to recognize which one supplies the similar information and to understand the peculiarity of each information and then he has to select the equipment as the proper source of information. Finally, mariner has to integrate necessary information effectively for safe navigation. This situation is not good environment in reducing mariners in conning place. Today we have to consider the information situation onboard. When we discuss them, mariner's human characteristics should be considered. What mariner has to execute when he face the specific environmental and traffic condition should be considered. It is desired that the necessary information be supplied with effective processing. The necessary information depends on the situation and the mariner's competency. All of the ship motion is decided by human factor as mariner. We have to understand what the human factor of mariner is.
 
4.6.1 Equipment onboard
 
 Equipments onboard had been assessed as useful instruments supplying effective information for mariner and have been installed. However, the discussion why it is useful is very small.[13] The evaluation should be based on the achievement of necessary functions. The discussion based on the function shall be carried out when newly developed equipments are evaluated. The functional approach defined by IMO corresponds to this issue. When we discuss the information equipment, the role of information for human information processing has to be discussed. Therefore, information processing of human has to be discussed and then the role of the information is defined. And we can evaluate the information equipment whether it is useful or not. For the study on human's information processing, ship-handling simulator will be applied because many kinds of situation for the discussion can be reappeared.
 
4.6.2 Support system
 
 In the first part of this section, the importance of condition of information supply is pointed. Necessary information has to be integrated and shown to mariner. In these days, Integrated Bridge System (IBS) or Integrated Navigation System (INS) is developed. They are developed to realize this idea. These systems are not a system intending to operate ship automatically without mariner. That is support system for mariner. They are developed to supply the necessary information of mariner in the situation and to supply easy handling device. All systems are developed as support system for human. The characteristics of data processing, displaying and steering devices have to take human characteristics into account. The rational and analytical discussions on it are very small. It has to be discussed which human's function can be replaced as the function of support system. Nevertheless, number of mariner in bridge has been reduced when newly developed support system was installed. For promoting the discussion on evaluation of function in newly developed support system, ship-handling simulator should be applied because human factor using them have not been clarified yet.







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