• Title, Summary, Keyword: Fine Structure

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Prediction of Bow Flare Impact Pressure and Its Application to Ship Structure Design - Container Ship and PCC - (선수 플레어 충격압력 추정과 구조설계에의 응용 - 콘테이너선과 자동차 운반선 -)

  • 김용직;신기석;신찬호;강점문;김만수;김성찬;오수관;임채환;김대헌
    • Journal of the Society of Naval Architects of Korea
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    • v.40 no.3
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    • pp.29-36
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    • 2003
  • In rough seas, bow-flare regions of the fine ships (container ship and PCC) are subject to high impact pressures due to the bow-flare slamming. And many ships suffer structural damages in that region, even though they were built under the bow structure strengthening rules of the ship classes. So, a new design method for bow-flare structure is highly required. In this paper, a new prediction method of the bow-flare impact pressure (in terms of equivalent static pressure) acting on the fine ships' bow is presented. This method is based on the 11 fine ships' damage analysis and the mechanisms of water entry impact and breaking wave impact. Calculation results of the bow-flare impact pressure and the shell plate thickness are shown and discussed. Through the example calculations, it was found that the present method is useful for the structure design of the fine ships' bow.

Prosodic Strengthening in Speech Production and Perception: The Current Issues

  • Cho, Tae-Hong
    • Speech Sciences
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    • v.14 no.4
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    • pp.7-24
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    • 2007
  • This paper discusses some current issues regarding how prosodic structure is manifested in fine-grained phonetic details, how prosodically-conditioned articulatory variation is explained in terms of speech dynamics, and how such phonetic manifestation of prosodic structure may be exploited in spoken word recognition. Prosodic structure is phonetically manifested in prosodically important landmark locations such as prosodic domain-final position, domain-initial position and stressed/accented syllables. It will be discussed how each of the prosodic landmarks engenders particular phonetic patterns, ow articulatory variation in such locations are dynamically accounted for, and how prosodically-driven fine-grained phonetic detail is exploited by listeners in speech comprehension.

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A Study on the Fine Structure of the Marine Diatoms of Korean Coastal Waters - Genus Thalassiosira 3

  • Lee, Jin-Hwan;Park, Joon-Sang
    • ALGAE
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    • v.23 no.3
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    • pp.187-199
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    • 2008
  • A study on the fine structure of the marine diatom Thalassiosira has been carried out during the periods from January 2007 to March 2008 in Korean coastal waters. As the third series of the Thalassiosira species, a fine structure, description, distribution and taxonomic remarks of the six Thalassiosira species were observed by means of light microscope and scanning electron microscope. The critical features of Thalassiosira species were a shape of external tubes of marginal strutted processes and labiate process. Six species showed each different shape of external tubes, marginal strutted processes and labiate process. The shape of external tube was divided into five types: T shape of Thalassiosira curviseriata, small-rounded shape of T. lundiana, double-layer form and flame shape of T. nordenskioeldii, tulip shape of T. punctigera and tooth-shape of T. tenera. This external character may be able to key character for positive identification of the Thalassiosira species. Of these Thalassiosira lundiana, T. minuscula and T. tenera were new records for Korean coastal waters.

Effects of Fine-slits for High Transmittance in MVA-mode LCD

  • Jung, Moo-Sung;Kim, Dae-Woo;Won, Tae-Young;Yoon, Hyung-Jin;Lee, Cheol-Soo;Yoon, Suk-In;Yoon, Sang-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • pp.443-445
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    • 2005
  • In this paper, we propose an MVA mode cell structure with improved optical characteristics. Our MVA cell has an electrode with fine-slits. Optical characteristics of our proposed structure were compared with those without fine-slits. Moreover, we varied the interval as well as the widths of fine-slits in order to appreciate the effect of fine-slits. Optical characteristics of these cells were calculated with 3DFEM solver, TechWiz LCD. It was confirmed that the transmittance can be improved by more than 7% with fine-slits.

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Fine Structure of the Cutaneous Pigments in the Black Widow Spider, Latrodectus mactans (검은과부거미 (Latrodectus mactans) 피부 색소의 미세구조에 관한 연구)

  • Moon, Myung-Jin
    • Applied Microscopy
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    • v.28 no.4
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    • pp.503-512
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    • 1998
  • Fine structure of the cutaneous pigments in the black widow spider, Latrodectus mactans are studied with light and electron microscopes. The cutaneous pigments are only observed in epidermal layer just beneath the cuticle. These pigments are compactly distributed around the spinnerets which located at caudal area of the abdomen. According to the fine structural characteristics of the pigment granules, two main types of guanine pigment granules-carotenoid vesicles and reflecting platelets - are observed in the cytoplasm of the epidermal cells. Morphological features of these pigment granules are characterized as the electron dense carotenoid vesicles and the electron lucent reflecting platelets. Marginal electron density of the carotenoid vesicle is different from that of internal region, whereas the reflecting platelets have laminated crystalline granules. Typiral structures of these pigment granules are very similar to those of invertebrate's chromatophores, especially erythrophores and iridophores. Moreover differentiation of these pigment granules are also originated from the small vesicles of Golgi complexes similarly to those of cutaneous chromatophores.

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Multi-Scaling Models of TCP/IP and Sub-Frame VBR Video Traffic

  • Erramilli, Ashok;Narayan, Onuttom;Neidhardt, Arnold;Saniee, Iraj
    • Journal of Communications and Networks
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    • v.3 no.4
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    • pp.383-395
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    • 2001
  • Recent measurement and simulation studies have revealed that wide area network traffic displays complex statistical characteristics-possibly multifractal scaling-on fine timescales, in addition to the well-known properly of self-similar scaling on coarser timescales. In this paper we investigate the performance and network engineering significance of these fine timescale features using measured TCP anti MPEG2 video traces, queueing simulations and analytical arguments. We demonstrate that the fine timescale features can affect performance substantially at low and intermediate utilizations, while the longer timescale self-similarity is important at intermediate and high utilizations. We relate the fine timescale structure in the measured TCP traces to flow controls, and show that UDP traffic-which is not flow controlled-lacks such fine timescale structure. Likewise we relate the fine timescale structure in video MPEG2 traces to sub-frame encoding. We show that it is possibly to construct a relatively parsimonious multi-fractal cascade model of fine timescale features that matches the queueing performance of both the TCP and video traces. We outline an analytical method ta estimate performance for traffic that is self-similar on coarse timescales and multi-fractal on fine timescales, and show that the engineering problem of setting safe operating points for planning or admission controls can be significantly influenced by fine timescale fluctuations in network traffic. The work reported here can be used to model the relevant characteristics of wide area traffic across a full range of engineering timescales, and can be the basis of more accurate network performance analysis and engineering.

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Crystal Structure of $TiO_2-SnO_2$ Fine Powders Prepared by Coprecipitation (공침법에 의해 제조된 $TiO_2-SnO_2$ 미분말의 결정구조)

  • 이종흔;박순자
    • Journal of the Korean Ceramic Society
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    • v.30 no.9
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    • pp.740-746
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    • 1993
  • TiO2-SnO2 fine powders prepared by coprecipitation from TiCl4-SnCl4 aqueous solution, and their crystal structures were studied. All the TiO2-SnO2 fine powders calcined at 180~$700^{\circ}C$ showed the complete solid solution between TiO2(rutile structure) and SnO2(rutile structure). This crystal structure of TiO2-SnO2 powders is thought to be originated mainly from the heterogeneous nucleation of Ti-hydroxde on the Sn-hydroxide with coherent structure.

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Integrated Optimization Design of Carbon Fiber Composite Framework for Small Lightweight Space Camera

  • Yang, Shuai;Sha, Wei;Chen, Changzheng;Zhang, Xingxiang;Ren, Jianyue
    • Journal of the Optical Society of Korea
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    • v.20 no.3
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    • pp.389-395
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    • 2016
  • A Carbon Fiber Composite (CFC) framework was designed for a small lightweight space camera. According to the distribution characteristics of each optical element in the optical system, CFC (M40J) was chosen to accomplish the design of the framework. TC4 embedded parts were used to solve the low accuracy of the CFC framework interface problem. An integrated optimization method and the optimization strategy which combined a genetic global optimization algorithm with a downhill simplex local optimization algorithm were adopted to optimize the structure parameters of the framework. After optimization, the total weight of the CFC framework and the TC4 embedded parts is 15.6 kg, accounting for only 18.4% that of the camera. The first order frequency of the camera reaches 104.8 Hz. Finally, a mechanical environment test was performed, and the result demonstrates that the first order frequency of the camera is 102 Hz, which is consistent with the simulation result. It further verifies the rationality and correctness of the optimization result. The integrated optimization method mentioned in this paper can be applied to the structure design of other space cameras, which can greatly improve the structure design efficiency.

Fine Seek Control of Extended Applicable Range for Optical Disk Drives

  • Ryoo, Jung-Rae;Jin, Kyoung-Bog;Doh, Tae-Young;Chung, Myung-Jin
    • Transactions on Control, Automation and Systems Engineering
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    • v.3 no.3
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    • pp.146-151
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    • 2001
  • Optical disk drive has excellent advantage of random accessibility of which performance is measured by access time. However, due to the increased rotational velocity of the disk and constraints of mechanical structure, two-stage seek algorithm which executes coarse and fine seeks sequentially has been adopted in most commercial optical disk drives. Although the laser spot is moved to a target track by a single seek operation, the limited operation range of the fine actuator restricts the application of the fine seek algorithm below a few hundreds of tracks. Especially, excessive movement of the objective lens causes a failure in generation of track-cross pulse and results in an unstable seek operation. In this paper, a new control algorithm for extending the fine seek range is proposed with an appropriate control structure. The coarse actuator is utilized to reduce the misalignment between the objective lens and the laser beam axis, and the fine actuator is controlled to follow the reference velocity trajectory. The proposed algorithm is applied to a CD-ROM drive to show its feasibility and some experimental results are presented.

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