• Title/Summary/Keyword: envelopes

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A Study on Loading Arm Envelope and Alarm Setting according to Ship Movement

  • Choi, Byoung-Yeol;Jo, Hyo-Jae;Choi, Han-Sik;Choi, Dong-Eon
    • Journal of Advanced Research in Ocean Engineering
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    • v.4 no.3
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    • pp.115-123
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    • 2018
  • This study was carried using the new approach method to design appropriately the Loading Arm length and the alarm setting according to ship movements on Loading and Unloading marine Berth. The quasi-static mooring analysis was performed to estimate 110,000DWT ship's movements based on environmental conditions such as wind, current and wave. The mooring motion of the ship is very important to determine the loading arm scope, and in this case, the operation condition is performed on the ship without considering the damaged condition of the mooring line because the ship movement in case of damage is larger than intact, and all operations are stopped, the loading arm being released due to control system. From the result of mooring analysis, motion displacements, velocities and accelerations were simulated. They were used to simulate the maximum drifting speeds and distances. The maximum drifting speeds were checked to be satisfied within drifting speed limits. The total maximum drifting distances were simulated with alarm steps of the new approach method. Finally, the loading arm envelopes using the total maximum drifting distances were completed. Therefore, it was confirmed that the new approach method for loading arm envelopes and alarm settings was appropriate from the above results. In the future, it will be necessary to perform the further advanced dynamic mooring analysis instead of the quasi-static mooring analysis and to use the precise computer program analysis for various environments and ship movement conditions.

Ultrastructure of the Matured Egg Envelope in Pond Smelt, Osmeridae, Teleostei (경골어류 바다빙어과 빙어의 성숙란 난막 미세구조)

  • Kim, Dong-Heui;Kim, Jae-Goo;Reu, Dong-Suck
    • Applied Microscopy
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    • v.41 no.1
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    • pp.13-20
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    • 2011
  • The ultrastructure of the matured egg envelope in Pond smelt, Hypomesus nipponensis belonging to Osmeridae, Osmeriformes were investigated by routine light and electron microscopes. The matured egg have two egg envelopes and have a single micropyle, which is thought to the pathway of sperm in the area of the animal pole. An outer egg envelope was surrounded by a follicular layer and outer surface of inner egg envelope have structure with high electron density. Also, the inner egg envelope consisted of 6 horizontal lamellae with higher electron density alternating with 5 interlamellae of lower electron density. Many grooves distributed on the outer surface of outer egg envelope, and the outer surface of inner egg envelope was covered by amorphous structures. In conclusion, the egg of teleost is surrounded by one egg envelope according to the studies on morphology of egg envelope up to the present. The fact that have two egg envelopes is a species specificity of Pond smelt and these ultrastructural characters of egg envelope can be utilized in taxonomy of teleost.

High-Reliable Classification of Multiple Induction Motor Faults using Robust Vibration Signatures in Noisy Environments based on a LPC Analysis and an EM Algorithm (LPC 분석 기법 및 EM 알고리즘 기반 잡음 환경에 강인한 진동 특징을 이용한 고 신뢰성 유도 전동기 다중 결함 분류)

  • Kang, Myeongsu;Jang, Won-Chul;Kim, Jong-Myon
    • Journal of the Korea Society of Computer and Information
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    • v.19 no.2
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    • pp.21-30
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    • 2014
  • The use of induction motors has been recently increasing in a variety of industrial sites, and they play a significant role. This has motivated that many researchers have studied on developing fault detection and classification systems of induction motors in order to reduce economical damage caused by their faults. To early identify induction motor faults, this paper effectively estimates spectral envelopes of each induction motor fault by utilizing a linear prediction coding (LPC) analysis technique and an expectation maximization (EM) algorithm. Moreover, this paper classifies induction motor faults into their corresponding categories by calculating Mahalanobis distance using the estimated spectral envelopes and finding the minimum distance. Experimental results show that the proposed approach yields higher classification accuracies than the state-of-the-art conventional approach for both noiseless and noisy environments for identifying the induction motor faults.

Evaluation and Improvement for Enforcement of the Waste Recycling System in Pohang City (쓰레기 종량제 실시 후 평가 및 개선방향 - 포항시 중심으로 -)

  • Ha, Yeong-Gil;Park, Kyung-Min;Lee, Sung-Kook
    • Journal of agricultural medicine and community health
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    • v.21 no.1
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    • pp.97-105
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    • 1996
  • This study conducted to determine the evaluation and improvement for enforcement of the waste recycling system in Pohang city and surveyed 4 areas at the southern and northern districts respectively by a team of two officials during the period 6 February 7 February 1995. The rates of the use for waste recycling system's envelope from home trash were 94.2% at the northern district and 92.8% at the southern district by areas, 95.6% at the group houses (apartments and tenement houses) and 91.3% at the separate houses by patterns of house, the low economic class 96.4%, the middle economic class 96.3% and the upper economic class 87.5% by the economic levels, and the bell method 96.5%, the container method 95.6%, door take method 86.1% in order, respectively. The trash from houses were garbage 57.4%, paper 18.7%, plastic 10.3%, fiber 7.9%, bottle 2.7%, metal and can 1.4%, and wood and rubber 0.7% in order. The rates of the reuse trash(reuse possible paper, plastic, bottle, can and metal) were 20.2% of the total, 21.8% at the southern district and 18.5% at the northern district by areas, 25.7% at the separate houses and 14.7% at the group houses(apartments and tenement houses) by patterns of house, and the door take method 34.3%, the bell take method 17.1% and the container take method 14.7% in order, respectively. There were the double envelopes of the plastic bag from stories 46.3% and the clear plastic bag 29.5% in the waste cycling system's envelopes. There were 1.9 double envelopes in the waste cycling system's envelopes. Garbage occupied more than half of the total trash, so it is need to be compost and provender.

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NUMERICAL STUDY OF AN EXTERNAL STORE RELEASED FROM A FIGHTER AIRCRAFT

  • Yoon, Young-Hyun;Cho, Hwan-Kee;Chung, H.S.;Lee, S.H.;Han, C.H.
    • Journal of computational fluids engineering
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    • v.13 no.4
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    • pp.80-85
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    • 2008
  • The prediction of the separation trajectories of external stores released from a military aircraft is an important task in the aircraft design area having the objective to define the operational and release envelopes. This paper presents the results obtained for store separation by employing commercial softwares, FLUENT and CFD-FASTRAN. FLUENT treats the rigid body motion by employing a remeshing scheme. CFD-FASTRAN uses Chimera(overset) grid and interpolations. It was found that, for the prediction of the trajectories and behavior of the stores separated from the wing, both codes show the good agreement with the experimental results.

Modified Generic Mode Coding Scheme for Enhanced Sound Quality of G.718 SWB (G.718 초광대역 코덱의 음질 향상을 위한 개선된 Generic Mode Coding 방법)

  • Cho, Keun-Seok;Jeong, Sang-Bae
    • Phonetics and Speech Sciences
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    • v.4 no.3
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    • pp.119-125
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    • 2012
  • This paper describes a new algorithm for encoding spectral shape and envelope in the generic mode of G.718 super-wide band (SWB). In the G.718 SWB coder, generic mode coding and sinusoidal enhancement are used for the quantization of modified discrete cosine transform (MDCT)-based parameters in the high frequency band. In the generic mode, the high frequency band is divided into sub-bands and for every sub-band the most similar match with the selected similarity criteria is searched from the coded and envelope normalized wideband content. In order to improve the quantization scheme in high frequency region of speech/audio signals, the modified generic mode by the improvement of the generic mode in G.718 SWB is proposed. In the proposed generic mode, perceptual vector quantization of spectral envelopes and the resolution increase for spectral copy are used. The performance of the proposed algorithm is evaluated in terms of objective quality. Experimental results show that the proposed algorithm increases the quality of sounds significantly.

Recent trends in advanced flight control

  • Kanai, Kimio
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.24.1-24
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    • 1996
  • The development of future aircraft that involves the expanded flight envelop will place increased performance requirements on the design of the flight control system. Maneuvering areas are expanding into flight envelopes characterized by significantly larger levels of modeling uncertainty than encountered in present flight control designs. Conventional flight control techniques that ignore the effects of large parameter variations, modeling uncertainties and nonlinearities, will likely produce designs with poor performance and robustness. Recent advances in modern control theories called advanced control theories, most notably the H$\_$.inf./ synthesis technique, adaptive control and neural network application, offer the promise of a design technique that can produce both high performance and robust controllers for next generation aircraft. This special lecture will survey the recent development in advanced flight control and review the possible application of advanced control theories.

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Comparison of Sound Source Localization Methods Based on Zero Crossings

  • Park, Yong-Jin;Lee, Soo-Yeon;Park, Hyung-Min
    • The Journal of the Acoustical Society of Korea
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    • v.28 no.3E
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    • pp.79-87
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    • 2009
  • This paper reviews several multi-source localization methods which estimate ITDs based on zero crossings (ZCs). Employing signal-to-noise ratio (SNR) estimation from ITD variances, these ZC-based source localization methods are more robust to diffuse noise than the cross-correlation (CC)-based one with less computational complexity. In order to take reverberant environments into account, two approaches detect intervals which dominantly contain direct-path components from sources to sensors because they may effectively provide reliable ITDDs corresponding to source directions. One accomplishes the detection by comparing the original and cepstral-prefiltering-processed envelopes, and the other searches sudden increase of acoustic energy by considering typical characteristics of acoustic reverberation. Experiments for comparison of these methods demonstrate that the approach with energy-based detection efficiently achieves multi-source localization in reverberant environments.

Micromechanical failure analysis of composite materials subjected to biaxial and off-axis loading

  • Ahmadi, Isa
    • Structural Engineering and Mechanics
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    • v.62 no.1
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    • pp.43-54
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    • 2017
  • In this study, the failure behavior of composite material in the biaxial and off-axis loading is studied based on a computational micromechanical model. The model is developed so that the combination of mechanical and thermal loading conditions can be considered in the analysis. The modified generalized plane strain assumption of the theory of elasticity is used for formulation of the micromechanical modeling of the problem. A truly meshless method is employed to solve the governing equation and predict the distribution of micro-stresses in the selected RVE of composite. The fiber matrix interface is assumed to be perfect until the interface failure occurs. The biaxial and off-axis loading of the SiC/Ti and Kevlar/Epoxy composite is studied. The failure envelopes of SiC/Ti and Kevlar/Epoxy composite in off-axis loading, biaxial transverse-transverse and axial-transverse loading are predicted based on the micromechanical approach. Various failure criteria are considered for fiber, matrix and fiber-matrix interface. Comparison of results with the available results in the litreture shows excellent agreement with experimental studies.

Thermal Effect of the Transparent Insulated Opaque Envelopes (투명 단열외피의 열적성능에 관한 연구)

  • Kim, Se-Hwan;Lee, Sung
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.4 no.4
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    • pp.19-24
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    • 2004
  • The thermal effect of a transparent insulated opake wall with solar energy was investigated theoretically. The heat gain through transparent insulated opake wall was studied for relative simple conditions. The stationary heat transport effect was studied for layer which is built on the opake wall. This study shows that a relative low solar radiation intensity causes a great heat reduction through the transparent insulated opake wall. Because the transparent insulation layer is mostly transparent to solar radiation, it is opaque to heat radiation.

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