非可展面を初期形状に持つ板材は、変形後の曲面上にを描くことで、見かけのひずみを知ることができる。本研究では、変形後の曲面に法を適用し、工学的に価値のある利用分野を探す。

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現在，造船分野では曲率線に従った方向へしか加熱できない「曲率線展開法」が用いられている．そこで本研究では，加熱方向が曲率線に縛られない「-面内ひずみ法」を提案し，-面内ひずみ法を用いて曲面に含まれる面内ひずみ量を測定し，鞍形を形成する加熱方案の自由度について検討した．

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Of recent years, the progress of E. D. P. S. (Electronic Data Processing System) has been very remarkable, and this system is now considered very effective method for ship construction.
In Yokohams Shipyard, I. B. M. 7090 Type which is installed in M. C. C. (Mitsubishi Computing Center) is used for mould loft calculation, such as calculation of developing off-sets for curved shell plates, bending off-sets for frames, and assembling off-sets for erection units etc.
And this calculation system has been adopted for several kinds and type of actual ships, such as 40, 000 DWT oil tanker and 10, 000 DWT super liner cargo ship.
The system is featured by many charactiristics, such as:
1) The number of shell plates which can be dealt with by this system are approximately 150-200 pieces of plate for either one 40, 000 DWT oil tanker or 10, 000 DWT cargo ship, which is 90% of total curved shell plates.
2) Only 1/1000 hours is needed to calculate the developing off-sets and bending off-sets for one plate.
3) Error in calculation can be kept less than ± 2.5mm in average, which is more accurate than the provious 1/10 scale mould lofting.
4) Since making input data is very simple, even unskilled worker can accomplish this work fast and without error.
In this first report, calculation methon for curved shell plater and twisted longitudinal frames will be explained.

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It is not always possible that a curved surface in the Euclid space of three dimensions is developed on the Euclid plane of two dimensions. Therefore, we use many approximate methods for the development of undevelopable curved surfaces which are shell plates, because the amount of expansion and contraction of parts of shell plates are not much in practice.
Then the author analysed these methods by differential geometry for the purpose of investigating the accuracy. Namely two geodesic lines being at right angles on the shell surface and being competent for making the correct developed plane, are found out by the calculus of variations, and the position of base points or base line of each method being relaitive to the geodesic line on the curved shell surface, are compared with the correct position of them on the developed plane, then the accuracy of each method is known.
And the author analysed the question of back-sets and the roll line of the shell plate by differential geometry.
After all, it was verified that the geodesic line method had the best accuracy in practice.

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As common shell plates have gentle curved surface, we can easily develop them by all kind of approximate developing method. But the cant shell plate is curved severly, therefore the development is not easy. Some shipbuilders use the mock-up mould or the approximate developing method that the cant shell plate is devided into many small parts, and these parts are devloped by the diagonal method. These methods are complicated and have not good accuracy.
Then the author devised the method of developing the cant shell plate, which is easy and has good accuracy. This method is an application of “the development of an undevelopable curved shell plate” which the author announced in the proceding journal of Zosen Kiokai, namely some temporary frame lines which are convenient for developing this shell plate, and the geodesic line which is suited for being formed undevelopable curved surface, are used, then the amount to shrink is known, and the cant shell plate is developed on a flat plane at a stretch.
The author intends to explain concretely the actual method of the development of the undevelopable cant shell plate.

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色空間がRiemann空間であるということが知られている.Riemann幾何学を利用することで,色空間にRiemann正規座標系と呼ばれる原点からのと等距離線で構成された極座標系を構築できる.これにより,等明度平面上で色相と彩度で表現されるマンセル表色系の拡張系を得ることが可能となる.しかし,空間内の曲率の値によって構築時にの交差が問題となることがある.曲率とは空間の曲がり具合を表したものでその符号によっての振る舞いが決まる.現在,色空間におけるRiemann幾何学はや計量については十分な検討がなされているが,曲率については十分な考察がなされていない.そこで本論文では,Riemann幾何学の性質の中でも曲率に着目し,Riemann正規座標系は負曲率の色空間でしか存在しないことを示す.また,CIELAB色空間とCIELUV色空間において,2組の色弁別楕円データとそのデータから計算された曲率の性質から,曲率との振る舞いの関係を示し,正曲率問題に対する解決策について考察する.

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The author calculated the equation of the terrestrial geodesic line and the distance between two points on the line. Let L: longitude l: geographic latitude θ: reduced latitude tanθ=b/a<tanl> a: terrestrial radius on the equator plane b: terrestrial radius on the axis Equation: -[numerical formula] Distance: -[numerical formula] s: distence

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現在，造船分野では曲率線に従った方向へしか加熱できない「曲率線展開法」が用いられている．そこで本研究では，加熱方向が曲率線に縛られない「-面内ひずみ法」を提案し，-面内ひずみ法を用いて曲面に含まれる面内ひずみ量を測定し，鞍形を形成した場合の加工方向の影響を検討した．

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現在，造船分野では曲率線に従った方向へしか加熱できない「曲率線展開法」が用いられている．そこで本研究では、加工方向が曲率線に縛られない「-面内ひずみ法」を提案し，-面内ひずみ法を用いて曲面に含まれる面内ひずみ量を測定し，椀形を形成した場合の加工方向の影響を検討した．

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We know numerous methods of developing shell plate, but these are approximate methods which are founded on the assumption that every shell plate is developable. However, actually some shell plats are formed undevelopable curved surfaces by the process to shrink or to extend some parts of them. Then, if the amount to shrink or to extend is known by simple method, we can develope and mark the figure of such a shell plate on a flat steel plate rationally.
The author intends to explain one method to get the amount to shrink, and to develope such an undevelopable, curved shell plate.

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We present a method for medial voxel extraction from large volumetric models. Our method first computes distance fields computed by our previous work. Next, we evaluate each voxel by pseudo geodesic distance of nearest boundary points of it. Since this computation is completely local, our algorithm is sequential algorithm and efficient for large data. We also demonstrate results of medial voxel extraction from large volumetric models.

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