日本航海学会論文集
Online ISSN : 2187-3275
Print ISSN : 0388-7405
ISSN-L : 0388-7405
100 巻
選択された号の論文の39件中1~39を表示しています
  • 原稿種別: 表紙
    1999 年 100 巻 p. Cover1-
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
  • 原稿種別: 付録等
    1999 年 100 巻 p. App1-
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
  • 原稿種別: 付録等
    1999 年 100 巻 p. App2-
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
  • 原稿種別: 目次
    1999 年 100 巻 p. Toc1-
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
  • 原稿種別: 目次
    1999 年 100 巻 p. Toc2-
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
  • 佐藤 尚登, 西 隆昭, 山下 享子, 平野 研一
    原稿種別: 本文
    1999 年 100 巻 p. 1-11
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    We have reported that the main towers of the large suspension-bridge have been considered macroscopically as a couple of the vertical electric dipoles from studying in Minami-Bisan Seto-Oohashi Bridge. In this paper, from experiments and theoretical considerations for 100kHz band waves near the Akashi-kaikyou-Ohhashi Bridge, it was confirmed that the sources of the secondary wave in the vicinity of the bridge is the metallic materials, "like main cable". Then, electric fields of the primary wave as well as the secondary waves re-radiated from both the two vertical towers and the metallic materials are derived theoretically. Furthermore, in the summer of 1997, a series of phase errors measurement of 8930 Loran-C chain was made, using both rho-rho Loran-C receivers and RTK-GPS/OTF. Taking notice of the phase errors within about ±200m from the bridge, the experimental values for Niijima station show the advances of about 0.5μ sec. Finally, it is shown that some aspects of the experimental results are reasonably interpreted by using the models of considering both a couple of vertical towers and the metallic materials to be vertical electric dipole antennas.
  • 鈴木 充雄, 大島 正毅
    原稿種別: 本文
    1999 年 100 巻 p. 13-19
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    Experiments to extract ships in the spatiotemporal images are performed aiming to provide useful supporting information for ship maneuvering instead of human eyes in the watching. The experimental data is a sequence of images including a moving (traversing) ship. This is obtained by a television camera fixed on an anchoring ship. The optical flow method is applied to the data to extract the vector field of pixel movement. The histograms of horizontal and vertical movement are used so that the background is rejected. The differentiated picture in the time domain is projected to the vertical axis to find the part the ship exists. This data is used to reject the wave part remained. The results for a set of sequential images to extract a ship have been so far satisfactory.
  • 坂井 丈泰, 惟村 和宣
    原稿種別: 本文
    1999 年 100 巻 p. 21-29
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    GPS (global positioning system) has insufficient capability in its vertical positioning accuracy for aircraft in the approach and landing phases of flight. Then, some augmentation systems including pseudolites are now under study to overcome this issue. The authors are considering of using precise clock to improve GPS vertical positioning accuracy. The simulation results show that the vertical positioning error is strongly correlated to the receiver clock estimation error. If one could know the receiver clock error precisely, the vertical error may be corrected significantly, while the horizontal error not. We explain that the aircraft equipped a precise clock, such as an atomic clock, toghther with GPS could obtain significantly accurate vertical position. Some simulation results would also be shown.
  • 天井 治, 長岡 栄
    原稿種別: 本文
    1999 年 100 巻 p. 31-40
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    The evaluation trials for navigation and arrival/departure procedures using the RNAV(Area Navigation) function of FMS(Flight Management System), which is an onboard system of aircraft, were carried out in Japan. Lateral navigation accuracy for the aircraft which flew on the newly established arrival or departure routes for the trials was estimated on the basis of ASR(Airport Surveillance Radar) data. The result of the analysis on the trajectory of one hundred thirty-eight flights shows that all aircraft flew on every segment of the routes including curved route portions with a lateral deviation value of less than 1.0NM.
  • 住谷 泰人, 白川 昌之, 小瀬木 滋
    原稿種別: 本文
    1999 年 100 巻 p. 41-49
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    ACAS (Airborne Collision Avoidance System) was developed to prevent near-midair-collision. The operational evaluation for ACASII with vertical RA(Resolution Advisory) function has been conducted in Japan since 1990. It uses pilot reports, ATC(Air Traffic Control) comment sheets, on-board data of ACAS II aircraft and radar data. This paper presents the evaluation results based on pilot reports from January 1, 1995 to December 31, 1997. In the evaluation, the data written in pilot reports are classified directly and correlated each other. The principal component analysis was applied to make clear the tendency of pilot reports or the correlation of the items of pilots reports. For the analysis, we could obtain the combination of a high correlation of the items of pilots reports.
  • 稲石 正明, 白 暁燕
    原稿種別: 本文
    1999 年 100 巻 p. 51-57
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    This paper deals with knowledge acquisition from ship operators' know-how that is related to ship collision avoidance. A new knowledge acquisition method is proposed that utilizes an autonomous distributed simulator and a data-mining algorithm. The method consists of five operations : (1) Setting of knowledge base for each ship, (2) Simulation of ship operation, (3) Storage of simulation results, (4) Data mining for extraction of a performance feature, (5) Evaluation of the performance feature. The prototype simulator is composed of three functions : ship operation, communication network and data mining. The prototype simulator is designed to perform as a knowledge acquisition tool. Evaluations of the prototype simulator performance and indispensable simulator functions are discussed.
  • 古荘 雅生
    原稿種別: 本文
    1999 年 100 巻 p. 59-66
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    The principal cause of the ship collision is "Lookout insufficiency". Why cannot another ship be watched visually immediately before the collision in the place where the ship collides? This study uses "visibility level" (hereafter, it is written as VL) as an index to express the easiness to watch the ship at sea to clarify the cause. It is a purpose of this study to understand the realities of the lookout based on the VL, and to propose navigator's lookout points in addition. To examine the visual and perceptional conditions of the ship by the influence of the sun light at sea, the visual environment at sea (luminance of the sky, luminance of the sea surface, and luminance of the ship) was measured by the experiment on board. Author shows the items of the results on this study as follows; 1. The relation between VL and the distance to the ship. 2. The visual perception on the ship and the relation to VL.
  • 今津 隼馬, 浦 環
    原稿種別: 本文
    1999 年 100 巻 p. 67-73
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    It is necessary to make numerous improvements to the Marine Operation System to increase the safety. Here, we try to find out the issues to improve on the Marine Operation System by a method of questionnaire. We expected that there were many near misses that had occurred at the work of ship's navigation bridge, as it seems to be especially related to human element in serious maritime casualties. So we tried to collect instance of near miss incident on board. The investigation was carried out in co-operation with a great number of seafarers (captains, officers and pilots) that belong to the Japanese flag ships and Pilot Association through their companies and associations. They were permitted to answer the questionnaire with keeping their name unmentioned and plural answers per an item. Some two thousand respondents participated in the investigation. The result of the investigation consists of both the instances of near miss incidents on board and personal matters of the respondents.
  • 鈴木 三郎, 松村 正純
    原稿種別: 本文
    1999 年 100 巻 p. 75-80
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    According to the Annual report of Maritime Safety Agency (Japanese Coast Guard) , 391 vessels requested the rescue to M.S.A. cause of collision in 1996. The report says that the collision is the major cause of the sea casualties. It is to be supposed that many vessels are not operated appropriately. We researched on those vessels which were not operated appropriately in Japanese teritorial water and found that Japanese pilots encountered such vessels at the rate of 4.4% on their piloting. Also we found that Inland Sea pilots and Yokosuka pilots often encountered such vessels in the Traffic Route.
  • 高山 久明, 合田 政次, 矢田 殖朗, 山口 恭弘
    原稿種別: 本文
    1999 年 100 巻 p. 81-89
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    In this study we experimented to clarify handling and sweeping method of a "Ro". Using a strain gage attached to the "Ro", we compared the skills of an "expert" seaman (A or A') with those of average skills, the middle (B) and those who have almost no experience (C). The results were as follows : 1) In the case of the "expert" seaman, the boat headed straight for the target point because push (Osae) and pull (Hikae) rate was relatively constant as was the tension on the "Haya-o". In addition the ship's pitch and roll was very small. 2) Under good sea conditions the average "Haya-o" pulling force was about 30% of each seaman's body weight. Comparing body weight the maximum value of "Haya-o" for the expert seaman was from 70%(A) to 120%(A'), and "Osae" was 1/3 or less than that of "Hikae". 3) For this study the "Ro" was positioned on the port quarter of the stern. It was found that although the power which moves the blade in the water depends on the position of the "Ro-gui", it was almost equal for "Osae" and "Hikae" when the boat was going straight.
  • 高岡 俊輔, 村山 雄二郎, 久保 雅義
    原稿種別: 本文
    1999 年 100 巻 p. 91-101
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    The largest problem of sail equipped motor vessel is poor manoeuvring by effect of sail. But this important problem has been left unsolved. In order to remove this defect, we develop a 2 dimensional bird's -eye view manoeuvring simulator with five automatic controls and discuss the manoeuvring ability using the simulator. Above five automatic controls are follows. (1) Ahead control (2) Turing control (3) Heave to control (4) Astern control (5) Aslant move control The results of the simulations on the simulator show a significant improvement in ship manoeuvring of sail equipped motor vessel.
  • 戸田 保幸, 定兼 廣行, 柳谷 昌信, 李 允石
    原稿種別: 本文
    1999 年 100 巻 p. 103-111
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    The ship speed near the berth is very low and the fluid flow around a ship hull is unsteady. So, the transient fluid motion should be considered to estimate the drag force acting on the ship hull. Especially, the lateral motion in a berthing maneuver of a VLCC starts from the rest and ends within one ship length. In that problem, the force is usually estimated using steady state drag force coefficient obtained by towing tank experiment, although some transient force model equations were proposed by some researchers. In the low speed and short time lateral motion, the vorticity is created by the body and grows up in the acceleration stage and the velocity induced by the vorticity affect to the body in deceleration stage. For this kind of problem, CFD is considered as the good tool to understand the phenomena. In the present study, the 2D CFD code is used for basic consideration of the phenomena to solve the flow in the cross section of the ship considering the ship is slender and the water depth is large enough. The flow fields and hydrodynamic forces for the some prescribed motions are computed. The results are compared with well-known potential flow code results and the preliminary experimental results.
  • 多田 光男, 村山 雄二郎, 沼野 正義, 緒方 純俊
    原稿種別: 本文
    1999 年 100 巻 p. 113-119
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    Authors surveyed and analyzed tidal current flows and structures by 300KHz ADCP and observed on ship movement by Data Recording System of T.S. Yuge-Maru (240tons) at the passage area of the Kurushima channel on August 26 and 27, 1997. Results are summarized as follows; (1) Remarkable changes in tidal flows were observed near Osumi Headland, Tsushima Island, Oshima Island, which can be regarded as the effect of island and headlands. (2) The upper layer flows of tidal current were almost similar to the lower layer flows except at several deep areas. (3) Effects of the tidal current for ship movement were controlled by the upper layer flows.
  • 久保 雅義, 榊原 繁樹
    原稿種別: 本文
    1999 年 100 巻 p. 121-130
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    Recently in various harbors, large and long period moored ship motions are caused by long period waves whose period are near to the natural period of surge. Rope breaking accidents, excessive compression and shearing deformations of fenders also happen in the case. So at an earlier stage, the moored ship is compelled to shift to offshore. In this paper, we propose a time domain analysis of moored ship motions in a harbor considering harbor oscillations and investigate the accuracy of the simulation by a field test for moored 90, 000DWT bulk carrier. It is clarified that the proposed time domain analysis of the moored ship motions considering harbor oscillations has a validity in accordance with the field test and some investigations.
  • 久保 雅義, 斎藤 勝彦, 沖 剛志
    原稿種別: 本文
    1999 年 100 巻 p. 131-137
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    In the previous papers, we proposed the prevention system of ship separation from quay wall. In the last experiment, we carried out a small scale model test which was similar to an actual mooring ship in order to clear some problems for practical application under wave condition. In this experiment, we improve the water cut-off property by a cover on the device. We carry out the experiments and compare the results with and without the cover. From the studies, the obtained results are summarized as follows : (1) The improved model has a better water cut-off property. (2) From wave conditions and the calculated mooring force of the system, we obtain a design principle of the system. (3) By the principle, we can calculate a quantity of entering water from outside of the system by rolling motion.
  • 久保 雅義, 山本 一誠, 淺木 健司, 鹿沼 洋司
    原稿種別: 本文
    1999 年 100 巻 p. 139-144
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    There are various prevention methods of mooring ropes breaking on board. These methods are Rope Protector, Rubber Protector, Serving, Racking, Splicing on a part of rope near a fair leader and so on. The effect of these methods is not researched well and depends upon seaman's experience. Rubber Protector, Canvas Protector and Splicing are chosen as the subjects of the study. Mooring ropes are trailed on boards and the quays, and then it is feared that mooring ropes are stained with something like sands. The strength of ropes with sands is researched, too. In this paper, the strength of mooring ropes is examined under the repeated load in order to evaluate prevention methods of mooring ropes breaking on board. The obtained results are summarized as follows : (1) Splicing on a part of rope near a fair leader is more effective than Rubber Protector or Canvas Protector in all. (2) Without prevention methods, sands make the strength of ropes weakened. (3) Prevention methods can keep the strength of ropes with sands.
  • 三田 重雄, 庄司 邦昭, 野々村 千里, 船城 健一
    原稿種別: 本文
    1999 年 100 巻 p. 145-151
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    The protective device that was made with the elastic resin is excellent in restoration. Therefore, when the collision ship is removed even if the ship collides with it the form almost returns to an original form. Recently, we are doing the research that checks the characteristic of the protective device by the model experiment and numerical value analysis and use the urethane foam as a model. In the previous paper, we discussed the characteristic of the time that the ship penetrated into it statically. The bow model that we used is 1 kind and entrance angle is 35 degrees. In the present paper, we report about the research result in the time that changed the measure of the bow. The following results are obtained. (1) When the entrance angle of the bow becomes big, the slope of a reaction force-bow penetration curve becomes steep. At this time, the change rate of the slope becomes steep with the increase of the entrance angle. (2) When the curvature radius of the top becomes big, the slope of the reaction force-bow penetration curve becomes steep a little. The influence of radius curvature decreases when the entrance angle becomes big. (3) These results almost agree with the numerical value analysis and model experiment.
  • 遠藤 真, 新村 俊二, 大谷 哲也, 正角 豊
    原稿種別: 本文
    1999 年 100 巻 p. 153-160
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    The authors have proposed a new safety management system for small vessels. The proposed system automatically assists a human operator in managing the safety operation of his vessel not only on the vessel but also remotely from the shore. The system has developed by using current advanced CNS technologies. The results of some trials showed that the system was useful to manage safety operations of small vessels and had reached the stage for practical use. The concept, the configuration and the feasibility of further applications of the system are reported.
  • 小林 弘明, 村田 信
    原稿種別: 本文
    1999 年 100 巻 p. 161-168
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    Ship handling techniques are already developed to elemental technique based on the concept of the technical education. And it is reported that the elemental technique training is effective and that the training shortens the training time comparing to the total training. Although the compound ability which is indispensable for upper class, the learning process of ship handling techniques have not been investigated sufficiently. In this paper, authors analyzed the learning process of compound ability by experiments using ship maneuvering simulator, and made a proposal of the following formula that the characteristics of learning process for ship handling techniques are described. A(n)=1-(1-a(n))e^<-(x/T(n))> Where A : the achieved level of the technique n : variable indicating the kind of technique to be trained a : the achieved level of the technique at the starting time of the training T : time constant indicating the speed of learning process x : proceeding time for learning It is possible that the necessary training periods for achievement level is obtained by the formula described above. As the result, the learning process of compound ability was clarified and it was certified that rational ratio of simulator-time to sea-time can be estimated based on the characteristics of learning process.
  • 井上 欣三, 臼井 英夫
    原稿種別: 本文
    1999 年 100 巻 p. 169-179
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    When the configuration of anchorages in harbour is designed, the shiphandling difficulty which is imposed on a ship navigating between the anchored ships should be considered. However, no research work has been done about the method to fix quantitatively the design elements of the configuration of anchorages under the condition that the shiphandling difficulty comes to an allowable level. The relationship betweeen the configuration of anchorages and the shiphandling difficulty was analyzed by applying the Environmental Stress Model as introduced in the previous paper. In the present paper, an algorithm to design the configuration of anchorages in harbour under the condition that the shiphandling difficulty comes to an allowable level was investigated. And a computer aided supporting system to design the configuration of anchorages was developed taking into consideration the userfriendly interface through graphical information on CRT display. It is avairable by using this system to select an alternative of the configuration of anchorages that the condition of the sizes of anchored ships and the shape and area of anchorage can be taken into consideration.
  • 西村 悦子, 今井 昭夫
    原稿種別: 本文
    1999 年 100 巻 p. 181-189
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    Japan's ports were major hubs of the international maritime container transportation system. However their roles as hubs have been disappearing these days because of efficient ports of other countries in Asia with relatively cheaper port charges. Therefore, it is important for Japan to reduce the cost related with ports and improve port services so as to increase the cargo volume to be handled in ports. For this, we propose a public berth system where the ship-to-berth allocation is dynamically performed. In this parer we discuss the efficient berth allocation by using Genetic algorithm (GA) . We conduct some numerical experiments with ship arrival and handling data in port of Kobe, resulting in the same handling performance with fewer berths available than those in Kobe.
  • 井上 欣三, 川瀬 雅勇己, 安田 克, 原 大地
    原稿種別: 本文
    1999 年 100 巻 p. 191-198
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    To compare the shiphandling difficulties of ports and harbours, human factors must be excluded. The reason is that the stress which is imposed on the mariner may be concealed by mixing individual differences based on the mariner's techniques, skills and personality in the shiphandling result. In the present paper, the concept of "Latent Environmental Stress" is introduced to avoid the influence of the individual differences of mariners and to guarantee the universality of the results in evaluating the shiphandling difficulty. The latent environmental stress is defined as the stress value found by the application of a standardized shiphandling process as follows. The own vessel proceeds along a fixed course at a fixed speed. And it does not take any action to avoid collision with other ships.
  • 勝原 光治郎, 亀山 道弘, 宮田 修
    原稿種別: 本文
    1999 年 100 巻 p. 199-207
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    Simulations of human escape on board, taking human factors into consideration, are carried out with parameters such as initial allocation of full members of passenger, person types, incident scenarios, and psychological variables. Effects of mass psychology on escape time are shown in 3-D graph. Based on these results, the method of escape analysis is proposed. First, preliminary analysis is to design general arrangement roughly modified by using the function of simulation program that shows bottlenecks of the routes. Second, escape simulations are carried out in necessary and sufficient conditions. The worst case and the best case are identified. The best case is the optimum one, of which the route should be that of the escape route design. The value of the best and worst case is regarded as the characteristics of design.
  • 吉村 浩, 合田 政次, 青島 隆, 山脇 信博
    原稿種別: 本文
    1999 年 100 巻 p. 209-213
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    Various harmful insects exist in the land facilities and houses. An investigation research is widely done about the harmful insects. And an insecticide against them is variously developed, and a report about their effect is done. Harmful insects exist in a ship as well as on the land. However, a research report regarding them is a few. In Nagasaki University, we are getting rid of harmful insects in the training ship Kakuyo-maru in June or July every year. However, approximately 3 months later, an inhabitation number of a cockroach returned as it was before. Because 20 years elapsed after the Kakuyo-maru constructed, it offered a cochroach comfortable trace to exist in the ship. Then, we have executed a biannual cockroach extermination using bait medicine from 1997. We continue a state that there is hardly any cockroaches, i. e. cockroach index is less than 0.1 through the year. Consequently, it is thought that the using of bait medicine indicates a persistent effectively in a ship.
  • 児玉 工, 木村 暢夫, 甫喜本 司, 天下井 清
    原稿種別: 本文
    1999 年 100 巻 p. 215-220
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    In general, rolling motion of small fishing boats shows nonlinear response relation to waves, because small fishing boats have characteristic shapes, such as flat bottom of boat and overhanging desk. So, we suppose that rolling motion of small fishing boats for scallop hanging type culture in mooring at trunk line also shows nonlinear response relation to waves, we confirmed it by tank tests used ship model of "MARUTOU-MARU" that has a typical ship shapes of fishing boats for scallop hanging type culture. As tank tests results, the rolling response system showed nonlinear aspect. In this paper, we tried to use a Neural Network Model as one of method to express this nonlinear rolling response system of small fishing boats. The results are obtained as follows : ・Output by Neural Network Model sufficiently correspond with experimental rolling motion, and a Neural Network Model could be used to forecast rolling motion of nonlinear response system. ・The nonlinear rolling response system in fishing operations is constructed by 4 inputs, inclination of wave, y-axis acceleration, z-axis acceleration, mooring tension and 1 output, rolling angle. ・A Neural Network Model is an effective method to express nonlinear response system, like the rolling response system of small fishing boats in fishing operations.
  • 甫喜本 司, 木村 暢夫, 天下井 清, 藤井 光昭
    原稿種別: 本文
    1999 年 100 巻 p. 221-227
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    This paper concerns with statistical forecasting of the sea surface movement in winter, which generates in Uchiura (Funka) Bay, Hokkaido. Traditionally, the above movement is often ragarded to be stationary and then an autoregressive model is used to construct the predictor. However, our statistical researches using measured data show the possibility that the movement does not always keep stationarity. From the above reason, in this paper, we consider geographical characteristics around this bay and then propose a predictor for forecasting sea surface movements by taking account of the possibility of nonstationarity. To discuss the validity of our predictor coupled by a locally stationary autoregressive model and Holt-Winters' method, forecasting accuracies are compared numerically among the predictors constructed by an autoregressive model, a locally stationary autoregressive model, a time varying coefficients autoregressive model and Holt-Winters' method. The results showed that our predictor gave the best forecasts among the above predictors.
  • 田中 隆博, 井上 欣三, 原 潔
    原稿種別: 本文
    1999 年 100 巻 p. 229-236
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    Large scale marine constructions such as an offshore airport and reclaimed land in ports and harbors change the topographical environment of water area and affect the marine traffic. The risk assessment of marine traffic for limited water area has been carried out from the viewpoint of mariners. In this paper, the authors proposed an evaluation method of marine traffic for wider water area, namely a macroscopic evaluation method, where the concept of Voroni Medial Axis (VMA) is taken into consideration. The VMA is obtained by computing the Voronoi Diagram for boundary points of the image of concerned water area, and extracts a simple continuous line. By applying this method, the results of the macroscopic evaluation for the topographical environment of harbor water areas was obtained.
  • 浪江 宏宗, 田中 直人, 安田 明生
    原稿種別: 本文
    1999 年 100 巻 p. 237-244
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    RTK-GPS is a real time positioning system of a few cm order of accuracy with carrier phase measurement of the radio waves from GPS satellites. The phase data, transmitted from the reference station, are necessary to deduce the positions. The service for RTK-GPS data dissemination has been operated experimentally since October in 1997 from several GPS-based control stations of GSI (Geographical Survey Institute in Japan) via a mobile communication system, called DMCA (Digital Multi-Channel Access). The authors tried RTK-GPS positioning simultaneously at a fixed point by two receivers with a single antenna, using different GPS-based stations, Nerima and Kawasaki, respectively via DMCA. The result shows that the both of 2drms are a few cm and the discrepancy between the averaged positions is a few cm. Although the base lines of both reference stations exceed 10 km, which is the boundary for the accurate positioning described in the instruction, the remarkable coincidence is obtained. Next, they tried the positioning on board a ship in Tokyo Bay under navigation. They confirmed that it worked well.
  • 山崎 祐介, 村山 義夫, 遠藤 真
    原稿種別: 本文
    1999 年 100 巻 p. 245-251
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
    The marine incident is the important source of the information on marine accident prevention measures. In this paper, comparing the marine incidents with the marine accidents, authors made investigation into similarities of the occurrence situation on both. And, the relation between the incident and the watchkeepers' duty state regarded as an important factor of the human errors could be analyzed furthermore. The findings are as follows. The marine incidents have many points of similarities to the marine accidents. And also, it became clear that the incidents happened around two hours later after the watchkeeping duty began. Considering these findings, authors suggest the optimum procedure to establish a method to investigate the marine incident. At first, the factors of the marine incident and the accident should be investigated, and they should be compared repeatedly. And, the investigation of the obvious relation between marine incident factors and marine accident factors should be done.
  • 原稿種別: 付録等
    1999 年 100 巻 p. App3-
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
  • 原稿種別: 付録等
    1999 年 100 巻 p. App4-
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
  • 原稿種別: 付録等
    1999 年 100 巻 p. App5-
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
  • 原稿種別: 付録等
    1999 年 100 巻 p. App6-
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
  • 原稿種別: 表紙
    1999 年 100 巻 p. Cover2-
    発行日: 1999/03/25
    公開日: 2017/01/15
    ジャーナル フリー
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