著者

黒田 貴子 池田 良穂

出版者

社団法人 日本船舶海洋工学会

雑誌

関西造船協会論文集 (ISSN:13467727)

巻号頁・発行日

vol.2001, no.236, pp.175-180, 2001-09-25 (Released:2017-09-06)

被引用文献数

2

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In the design process of a passenger ship, ship owners try to improve the seakeeping quality of a ship by changing ship hull shape and size, or by installing additional anti-motion apparatuses, like a fin stabilizer, an anti-rolling tank, a ride control system or an anti-pitching fin. Such improvements usually coat the ship owners. They consider the merit and the demerit of each choice carefully, and then decide which way is the best one from the point of view of operation and economics. In this paper, an evaluation method of seakeeping quality from the economical point of view is proposed. The method is divided into three parts ; prediction of ship motions in waves, prediction of vomiting ratio of MSI(Motion Sickness Incidence)of passengers on the ship, and prediction of increases of share of demand for the ship due to improvement of the vomiting ratio. The evaluation method is applied to two domestic routes in Japan.

著者

川中 幸一 馬場 信弘

出版者

社団法人 日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

vol.178, pp.33-40, 1995-12

参考文献数

10

被引用文献数

10 2

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Computational results of a two-dimensional gravity current in a lock-exchange flow is presented in which a finite volume of homogeneous fluid was released instantaneously into another fluid of slightly lower density when a lock gate was opened. The computations were performed in a two-dimensional channel by solving the incompressible Navier-Stokes equation for an inhomogeneous fluid, the continuity equation and the transport equation for solute by the finite volume method. For accurate representation of small density difference, the density variation relative to the characteristic density difference was used as one of primitive variables. The finite volume formulation holds the conservative property with respect to mass at the boundaries as well as at the density interface so that the total mass of the two fluids with different density remains constant. Some of standard numerical schemes were used to examine their performance to the density jump of the interface. The computed gravity current moves steadily in an initial phase, and the front speed decreases with distance in a self-similar phase when an internal bore on the interface reflected from the back of the lock reaches the front of the current. The effects of the bottom boundary layer on the internal structure of the current is investigated from numerical experiments with no slip and free-slip boundary conditions. The volume of the diluted fluid in a gravity current by the entrainment of ambient fluid is evaluated as a function of time to quantify the mixing. The result indicates that at low Reynolds numbers the subsequent mixing occurs in the early stage of the evolution of the gravity current in a lock-exchange flow.

著者

片岡 秀太郎 宮田 秀明 金井 亮浩

出版者

社団法人 日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

vol.182, pp.113-120, 1997-12

参考文献数

9

被引用文献数

3

---

A new technique for PPS (performance prediction simulation) to design sailing boats is developed. The performance of a sailing boat with 6 degrees of freedom is predicted. The boat sails in the simulation with automatic steering to get steady state and with automatic sail trimming to get better VMG (Velocity Made Good). With this technique the steady performance of sailing boats is predicted with sufficient accuracy on various conditions. This system is applied to the design procedure for a IACC (International America's Cup Class) sailing boat for which the steady sailing attitude plays an important role for the sailing performance.

著者

大沼 覚 山本 鷹司 中野 元博 尾上 光賢

出版者

社団法人 日本船舶海洋工学会

雑誌

西部造船会々報 (ISSN:0389911X)

巻号頁・発行日

vol.38, pp.93-120, 1969

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Qualitative investigation has been carried out on the vibration of superstructure which is assumed to be a shear beam of uniform section on elastic foundation. Coupling effect with vertical vibration of main hull is also studied, and is assessed to be less than 5% on the frequency. Calculation procedure of the vibration, using electronic digital computer, is established treating the deck houses as an array of shear beams connected each other by elastic springs. The qualitative investigation mentioned above is extended in more detail by this procedure. The results show that there exists a relation among the calculated frequencies, which is similar to so-called Dunkerley's formula, i.e. (1.07/Nc)^2=(1/Nr)^2+(1/Ns)^2 where Nc, Nr and Ns are calculated frequencies and Nc; Considering finite values of both vertical-and shearing springs. Ns; Frequency in the limiting case where elasticity of vertical springs tend to infinity. Nr; Frequency in another limiting case where elasticity of shearing springs tend to infinity. Then the lowest frequency is effected predominantly by the lower one of both Nr and Ns. In the actual structures Ns has simple relation with the height of the structure, i.e.: Ns=2600-90H cpm (H: height of superstructure, excepting poop Dk house) On the contrary, Nr undergoes significant changes due to the variety of structure. Vibration experiments have been carried out on 10 ships, and the vibratory behavior of the superstructures is observed. Comparison between measured frequency and calculated value shows that the latter is higher than the former by about 30%. Thus the lowest frequency can be estimated applying the empirical coefficient (0.73) to the calculated values. Estimated frequencies of 10 ships by digital computer agree within±10% of error with their measured values. A brief discussion on the effect of designing factors on the frepuency is investigated by the procedure mentioned above. Finally the simplified method is proposed to calculate natural frequency. Estimated frequencies of 14 ships by this method agree with their measured values within±15% of error.

著者

福田 淳一 小野 雄二

出版者

社団法人 日本船舶海洋工学会

雑誌

西部造船会々報 (ISSN:0389911X)

巻号頁・発行日

vol.28, pp.53-61, 1964

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The authors tried on to substitute the average sea states by the assumed fully-developed wave spectra following a formula of the Neumann-type: [r(ω,χ)]^2=C_1/ω^6exp(-C_2/ω^2)cos^2χ:0≦ω≦∞ -π/2≦χ≦π/2 The coefficient C_1 and C_2 can be calculated as follows: [numerical formula] H^^〜_<1/3>: average wave height in the average sea states T^^&esim;: average wave period in the average sea states H^^〜_<1/3> and T^^&esim; can be defined respectively as a function of wind velocity based upon the average value of observations. Then, the significant wave height and the average wave period of the assumed wave spectra coincides respectively with the each of the average sea states. A sample of the application of the substitutional wave spectra for the average sea states were presented; The relative vertical bow motions with respect to the water surface of a bulk-carrier in ballast conditions were estimated in the average sea states of North Atlantic, and the critical fore drought with respect to the bow emergence was investigated. The derived results were rather reasonable.

著者

有冨 正男 富 武満

出版者

社団法人 日本船舶海洋工学会

雑誌

西部造船会々報 (ISSN:0389911X)

巻号頁・発行日

vol.87, pp.185-200, 1994

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Detailed considerations are given for the motion of Foucault's pendulum suspended by a string from a support that can rotate freely. It is well-known that the vertical axis attached to the support of the pendrum rotates with uniform angular velocity due to Coriolis force induced by the rotation of the Earth. In an earlier work, one of the present writers derived an equation of motion for a load suspended from a slewing jib crane attached to a rotating vertical pole. This equation is applied to analyze the motion of Foucault's pendulum. It is shown that the centrifugal force abuot the suport may have a signifficant effect on the pendulum motion. Exact solutions are obtained and experiments on Foucault's pendulum are then conducted to confirm the theoretical predictions.

著者

川口 勝義 浦 環 折出 光宏 坂巻 隆

出版者

社団法人 日本船舶海洋工学会

雑誌

日本造船学会論文集 (ISSN:05148499)

巻号頁・発行日

vol.178, pp.657-666, 1995-12

参考文献数

9

被引用文献数

8 7

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The ALBAC designed by the authors and constructed in 1992 is a prototype of shuttle type autonomous underwater vehicles. The ALBAC was developed for the oceanographic measurement of water column on the way and from the seabed.<BR>The vehicle does not have a propeller thruster but moves aside by gliding. To carry out the mission, the software includes three simple fuzzy controllers for longitudinal and lateral motion. The longitudinal motion controller displaces the longitudinal coordinate of the location of the center of gravity (C. G.) and controls the gliding angle, respectively of the vehicle. Two lateral motion controllers also displace the lateral coordinate of C. G. and control azimuth and yaw rate. The parameters of the fuzzy rules were optimized by using the Evolution Strategies on the simulator, and examined based on the motion data of every trial. 300-meter depth sea trials were successfully conducted in April of 1995 at the Suruga Bay of Japan.<BR>Consequently, the ALBAC is highly reliable and can be easily operated to carry out the mission to measure the profile of scientific data.

著者

吉田 孝太郎

出版者

社団法人 日本船舶海洋工学会

雑誌

造船協會會報 (ISSN:18842054)

巻号頁・発行日

vol.1925, no.37, pp.21-36, 1925 (Released:2009-09-04)

著者

惠藤 浩朗 佐藤 千昭 増田 光一 居駒 知樹 清水 研 畔柳 昭雄 山口 順子

出版者

社団法人 日本船舶海洋工学会

雑誌

日本船舶海洋工学会論文集 (ISSN:18803717)

巻号頁・発行日

vol.19, pp.245-253, 2014 (Released:2014-08-28)

参考文献数

18

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An innumerable number of buildings in the coastal part of the east side of Japan were devastated by the Great East Japan Earthquake and Tsunami. Medical institutions also suffered the damage caused by tsunami, and the function to carry out the medical act has been spoiled. And the disabled concentrated on the medical institution which avoided tsunami damage. Under such circumstances, assistance from the water area began three days after the earthquake disaster, and much support supplies reached the stricken area. It was revealed that the support from the water area including the river was extremely effective against the stricken area.And then, the Tokyo Inland Earthquake disaster was assumed, floating medical support system installed in the quay of Arakawa River in Tokyo was proposed. Floating medical support system is movable; furthermore, it is built in the structural system of having very high isolation characteristics. Therefore, feasibility study such as selection of suitable setting position of this floating structure on Arakawa River, floor planning and flow planning at the time of always and a disaster, facilities and storage of various material,structural strength of the floating base, and the effects of disaster risk reduction was carried out about floating medical support system.

著者

中村 昌彦 百留 忠洋 吉田 弘 青木 太郎

出版者

社団法人 日本船舶海洋工学会

雑誌

日本船舶海洋工学会論文集 (ISSN:18803717)

巻号頁・発行日

vol.9, pp.139-153, 2009 (Released:2009-10-08)

参考文献数

12

被引用文献数

4

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A small AUV "MR-X1" was developed in 2000 for detailed investigation of the seafloor and marine organisms at JAMSTEC (Japan Agency for Marine-Earth Science and Technology). In order to assure high maneuverability under low-speed cruising and good hovering performance, the motion of the vehicle is controlled by five thrusters. When the vehicle was built, PID control was implemented, but in order to improve control performance, renovation of the vehicle operating system has been ongoing since 2007, and a model based control (LQI control) is due to be adopted when this is complete.The paper summarizes the mathematical model of the vehicle and the design method of the motion and path controller, and shows successful numerical simulated results.

著者

赤崎 繁 井口 常雄 出淵 巽 小野木 敏夫 加茂 正雄 加藤 弘 菅 四郎 榊原 鉞止 斯波 孝四郎 鈴木 恒太郎 玉井 喬介 常松 四郎 朝永 研一郎 南波 松太郎 松本 良一 湊 一磨 八代 準 山本 開藏 山縣 昌夫 吉識 雅夫 渡邊 賢介

出版者

社団法人 日本船舶海洋工学会

雑誌

造船協會會報 (ISSN:18842054)

巻号頁・発行日

vol.1949, no.80, pp.53-66, 1949 (Released:2007-05-29)

著者

中村 昌彦 梶原 宏之 稲田 勝 原 正一 星野 邦弘 黒田 貴子

出版者

社団法人 日本船舶海洋工学会

雑誌

日本船舶海洋工学会論文集 (ISSN:18803717)

巻号頁・発行日

vol.4, pp.95-105, 2006 (Released:2007-04-06)

参考文献数

6

被引用文献数

2

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Recently, in domestic shipping, a shortage of crew members resulting from the severe labor environment and the aging of members are serious problems, and there is concern about stable transportation becoming difficult because of this. The hiring of younger crew members by improving the labor environment and reducing the labor load is therefore an important target. The automatic mooring is one means of mitigating the labor load of standby operations. If the shift of the mooring tension induced by tide level change and the draft change while loading can be prevented, and moreover, if the hull position can be kept automatic within the allowable limit, the labor load can be reduced. In this research, a simulator which calculates mooring tensions and ship motions was built first, and calculation accuracy was checked by model experiments. The controller was then designed using the simulator and the performance was verified by tank tests. Successful results are shown.

著者

市来崎 哲雄 山本 郁夫

出版者

社団法人 日本船舶海洋工学会

雑誌

日本船舶海洋工学会論文集 (ISSN:18803717)

巻号頁・発行日

vol.5, pp.9-13, 2007 (Released:2007-09-11)

参考文献数

8

被引用文献数

2

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The authors developed a robotic fish that swim with fins that apply flexible oscillating fin technology. The Carp Robot, whose artificial appearance was created through three-dimensional CAD processing of numerical data for the outer shape of living carp sampled through three-dimensional laser digitizing. Although this robotic fish was developed for the amusement field, it is thought to contain key technologies for the development of work robots in the future. For example, "mechatronics" technology involving center-of-gravity shifts, FM radio wave technology for navigation, CCD image data transfer technology for observation, and other technologies were applied to the robotic fish. In this report this robotic fish will be used as examples to explain these development achievements.