Abstract: The authors have advanced the research of systematic validation on Radar/ARPA simulator training for beginners (students) in order to validate and to propose the effective training method. The technique needed for radar positioning and plotting was systematically classified from the viewpoint of degree of rapidity and accuracy. Then, we have already presented the paper that the result of the simulator training could be quantitatively and qualitatively arranged in the International Conference such as INSLC. This time, further we had been analyzed the result of the radar simulator training, and the mastering characteristics in the radar simulator training for beginners were examined. The training that we made to be an object this time is positioning. And, the similar radar simulator experiment for the mate was carried out. By comparing these results, it was possible to grasp the training tendency of beginners. Then, it was proven that the training frequency and the training hours as a necessity could be presented. In this paper, the result of the radar simulator training is quantitatively and qualitatively evaluated, and mastering characteristics of beginners and ideal way of beginners training are mentioned

　

 Radar/ARPA simulator is used for the trainings of (1) positioning of own ship, (2) plotting of target ship and (3) collision avoidance. In these trainings, the ability of accurately interpreting the radar image is required. The technical element, which is indispensable to this ability, has already been clarified by verification experiment using simulator and on-board radar. By analyzing above-mentioned three elemental techniques, the relation between simulator training and training using on-board radar is clarified, and the matter required for the simulator training is proven. For example, "position fix", that is one of the elemental techniques, includes skills as follows;

 In addition, the level of these skills can be obtained by measuring the errors of positioning, the time required for the positioning and so on. The level of these skills can be analyzed quantitatively. These levels present the characters of trainees too, so the effective training will be done in briefing and/or debriefing. The training effect will be measured and discussed by these levels measured using radar simulator and on-board radar.

　

 In Japan radar simulator training is carried out based on the STCW convention (1995) and the Law for Ships' Officers of the municipal law. As acquisition requirement of the certificate of competency, it is being divided into "Rader Observer Course" and "Radar/ARPA Simulator Course". In the former training, the on-board radar is used as basic operation of the radar and interpretation method of the image. In the latter training, the simulator is used as a training of analysis of targets and collision avoidance.

 However, each organization has been carrying out the training using their own method, and it was not unified on concrete training method and evaluation method of the training result. As a concrete training, the model course is shown by IMO. But, the model course is made basically for the person with their sea experiences, and this does not always coincide with present status in Japan. Because radar simulator training in Japan is usually carried out for beginners or students who have not or very short sea experience. It is necessary that the training instructor sufficiently recognize this point.

 In revised STCW convention (1995), the training using Radar/ARPA simulator became enforcement. And, the training using more than two own ships was added by this revision.

　

3.1 Outline of the Positioning Training

　

 The experiment by the radar simulator was carried out in order to systematically evaluate the radar simulator training. And, the similar experiment was carried out successively after the simulator training using on-board radar equipped a training ship in order to clarify effectiveness of the radar simulator training and the problem. Both of experiments were carried out in Tokyo University of Fisheries (TUF). Examinees are students without the sea experience.

　

(1) Radar Simulator Experiment in TUF

 The own ship position is fixed in Tateyama Bay in the experiment. Tateyama Bay is the sea area in the entrance south in Tokyo Bay. Each examinee chooses three land objects on the basis of the radar image, and distance and azimuth of the selection object are measured. Using only distance data of three objects, the ship position was decided by the description. It continues to each examinee in totals 3 times. Examinees are 71 persons in total, and they were divided into two groups by the existence of the briefing (with briefing 34, without briefing 37). The experiment was carried out throughout totals four days.

 The briefing was conducted about 10 minutes per one examinee prior to the first experiment. In the briefing, the following were concretely explained for each examinee: selection criterion of the object, correspondence with chart, reflection characteristic of radar radio wave, etc. And, all the examinees have already had a basic knowledge on positioning principle and positioning method of the radar. Though the training for the machine operation was also important in the beginner training, the adjustment of the equipment was made unnecessary in order to extract only the positioning technology. The radar is fixed in the 6-mile range, and gain and tuning, etc. have been adjusted beforehand. Each examinee was in a base of the same condition.

　

(2) On-board Radar Experiment in TUF

 The experiment using the on-board radar was made to anchor training ship "Umitaka Maru" (TUF, 1,800GT) in Tateyama Bay, and it was carried out in the setting equal to the simulator experiment. The anchorage position is almost equal to the position of the simulator experiment, and it was done for students of 18 persons who participated in the simulator experiment. And, the similar experiment was also carried out to mate of 3 persons in order to compare with the learning process of beginners. Positioning frequency of each examinee is one time. The standard position was used the DGPS position at the end of measuring the 3 objects (using the correction data from Kensaki station 11.2 nautical miles far from here).

　

(3) Radar Simulator Experiment in Toba National College of Maritime Technology (TCMT)

 Using the experimental result of the above-mentioned mate, the approximation that shows the learning process of beginners is proposed. Positioning experiment, which used the radar simulator in TCMT, was newly carried out in order to verify the validity of the approximation. Examinees are 8 persons, and condition and setting of the experiment are similar to the experiment on the last time. Experiment frequencies in a day of one examinee are 3 times. Since such experiment was carried out two days in totals, one person total 6 times was examined.

　

3.2 Evaluation Item

　

 It is necessary to clarify the training purpose in order to effectively and efficiently carry out the radar simulator training. Then, the training result must be appropriately evaluated. Therefore, the evaluation item is found every required, and evaluated value must be quantitatively extracted. Referring to the radar positioning, the basic concept of the training evaluation is described.

 First, it is necessary to clarify the technique necessary for the radar positioning. This technique is obtained by tracing the action of the mate until it gets the ship position using the radar, and analyzing the action in the element unit. Next, this analyzed item is made to be the elemental technique item, and dealing with evaluation item was individually set.

 It is required that the positioning is made accurately and quickly, when radar positioning on board is assumed. Though it is a contradictory matter, the positioning must be politely and quickly carried out. Then, the evaluation item is classified and shall be quantitatively and qualitatively evaluated from the viewpoint of "degree of accuracy" and "degree of rapidity". Evaluation item of the positioning training is shown in Table 1.

　

4.1 Validation for Radar Simulator Training

　

(1) Validation from the Viewpoint of Degree of Rapidity

　Fig. 1 shows time required to the ship's position decision by the existence of briefing. Transverse axis is the training frequency, and vertical axis is the training hours (second). As a result of the statistical processing by dispersion analysis, the shortening of working time by repeating the training was confirmed (p=0.0093,5% level of significance). However. the difference by the existence of the briefing could not be recognized. "Degree of rapidity " was improved by repeating the training rather than the briefing effect. This result was also same on either other working time (selection, measurement, description).

 The first training result shows that much time is needed in the group, which received the briefing. Fig.2 shows the total time for the positioning according to the male and female students. In the first time, it is proved that much time is needed in female student. There was a similar tendency for the object selection and description time. It can be guessed that the female student who received the briefing becomes more prudent. Actually, in the briefing, the female student had many questions comparing with male student, and they intended to understand completely. And, there were many female students who were nervous, since the working time was measured by the instructor (the evaluation person). Prudence and strain seem to affect the time.

 In the training for beginners, training method considering psychological state of the examinee is important. However, this happens in an initial stage of the training, and with the advance of the training, it has appeared of the effect by the existence of the briefing. Although the significance by the sexes was examined using the third experimental results, the significance could not be found.

　

　

(2) Validation from the Viewpoint of Degree of Rapidity

 Fig.3 shows the mean value of the positioning error according to the briefing. The effect of the briefing has remarkably appeared. The significance was confirmed from the result of the dispersion analysis (p=0.0439). On the accuracy, it was proved obviously that the effect by the briefing was reflected. In the meantime, there is no improvement of the accuracy, when the briefing was not received. It can be guessed with the effect by advancing for next training without teaching the trainee right or wrong of the training result. For the beginner without the operational experience, it is difficult to analyze by himself or herself right or wrong of the positioning result. Therefore, it is proved that the briefing is very important in the training for beginners. The mean value of distance error according to sexes and briefing is shown in Fig.4.

 Fig.5 and Fig.6 show distribution diagram of positioning error. The center is true position, and vertical axis is error in latitude (meters), and transverse axis is error in longitude (meters). Although the maximum error is 1,000 meters in the figure, the errors larger than 1,000 meters were often found in the non-briefing student's data. In comparison with both figures, the degree of convergence in the data of student who received the briefing is remarkable.

 Fig. 7 and Fig.8 are histograms of the intercept angles of targets selected by students. Transverse axis takes the intercept angles in the 20-degree interval, and the frequency is taken in vertical axis. It is found that the intercept angles in the group, which received the briefing, is concentrated in 120 to 140 degrees. It is based on the result of briefing that intercept angle of 120 degrees is ideal for positioning, when three objects are chosen. It seemed to improve the accuracy by faithfully executing the advice in the briefing.