• Title/Summary/Keyword: Modelling and evaluation

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Use of Methods and Evaluation Systems of the Impact Mitigation Principle in German EIA (독일 환경영향평가에서의 자연환경의 평가절차)

  • Peters, Wolfgang
    • Journal of Environmental Impact Assessment
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    • v.2 no.2
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    • pp.49-53
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    • 1993
  • Before the EIA was established in the Federal Republic of Germany, the impact mitigation principle - a planning instrument, which has its legal foundation in the German nature conservation legislation already had {and still has} the function to valuate environmental impacts. The valuation principles and methods which have been developed in correlation to this instrument are now also used in the EIA. Particularly for the valuation of alternating effects on the different ecological landscape functions and for the valuation of ecological mitigation and compensation measures this valuation methods are used. These methods base on a special kind of modelling nature and environment Following the aim of the nature conservation act, which is to save the capacity of the landscape to perform its essential functions, not the ecological factors (soil, water, air etc.) itselfs are evaluated but the ecological functions of the landscape, which are based on the ecological factors.

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A Design Evaluation of Strained Si-SiGe on Insulator (SSOI) Based Sub-50 nm nMOSFETs

  • Nawaz, Muhammad;Ostling, Mikael
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.5 no.2
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    • pp.136-147
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    • 2005
  • A theoretical design evaluation based on a hydrodynamic transport simulation of strained Si-SiGe on insulator (SSOI) type nMOSFETs is reported. Although, the net performance improvement is quite limited by the short channel effects, simulation results clearly show that the strained Si-SiGe type nMOSFETs are well-suited for gate lengths down to 20 nm. Simulation results show that the improvement in the transconductance with decreasing gate length is limited by the long-range Coulomb scattering. An influence of lateral and vertical diffusion of shallow dopants in the source/drain extension regions on the device performance (i.e., threshold voltage shift, subthreshold slope, current drivability and transconductance) is quantitatively assessed. An optimum layer thickness ($t_{si}$ of 5 and $t_{sg}$ of 10 nm) with shallow Junction depth (5-10 nm) and controlled lateral diffusion with steep doping gradient is needed to realize the sub-50 nm gate strained Si-SiGe type nMOSFETs.

Determinants and Optimum Modelling of Logistics Outsourcing Strategy (물류(物流) 아웃소싱 전략(戰略) 결정요인(決定要因) 및 최적(最適) 모델)

  • Song, Gye-Eui
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.13
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    • pp.283-302
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    • 2000
  • The firms aim to acquire services and costs advantage from logistics outsourcing strategy. But it is very important to select optimum service provider. A checklist of the criteria for the evaluation of service providers follows : service quality, low cost, logistics information system, service network, financial stability, investments in plant and equipment, management attitude and lookout for the future strategic fit, cultural and psychological barriers etc. Also, a 8-step implement of logistics outsourcing strategy will be of help for maximizing benefits of logistics outsourcing. It follows : 1-step : logistics environment analysis, 2-step : check service provider availability, 3-step : logistics outsourcing determinant analysis, 4-step : select of optimum service provider, 5-step : contract with optimum service provider, 6-step : identify of remaining barriers, 7-step : performance of logistics outsourcing, 8-step : evaluation.

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Numerical Study on Fire Performance of Hollowcore Slabs (할로우코어 슬래브의 내화성능에 대한 수치해석 연구)

  • Min, Jeong-Ki;Woo, Young-Je
    • Journal of Korean Association for Spatial Structures
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    • v.15 no.3
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    • pp.95-102
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    • 2015
  • Numerical model on precast prestressed concrete (PC) hollowcore slabs using 11.3 mm diameter 7-wire stand was developed based on finite element analysis. In order to validate the modelling, previous experiment results with respect to prestressed solid concrete slabs were used and compared throughout the course of fire exposure. In addition to, the fire performance of hollowcore slabs with different aggregate types, moisture contents and compressive strength of concrete was investigated. As a result, it can be seen that the type of aggregates and moisture contents used in hollowcore slabs can affect the fire performance as well as temperature developments.

Structural Characteristics Evaluation Considering Construction Circumstances of Cheomseongdae (첨성대의 축조현황을 고려한 구조적 특성평가)

  • Kim, Ho-Soo;Kim, Jung-Hwan
    • Journal of Korean Association for Spatial Structures
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    • v.15 no.3
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    • pp.69-76
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    • 2015
  • Cheomseongdae is the masonry stone structure with the cultural and historical values. But, this structure has the various damages such as cracks, gaps, slope variations and ground subsidence. So, the interests for the safety security in the structural parts have been increased. Therefore, this study performs the structural modelling which considers the several damage cases, and then evaluates the structural behavior characteristics through the discrete element analysis. Especially, this study checks the swelling and displacement gap of the whole structure and the separation between the neighboring members.

A Study on the Evaluation of Automatic Steering System of Ships in Folowing Seas (추사파중을 항행하는 선박의 자동조타 시스템 평가에 관한 연구)

  • 이경우;손경호
    • Journal of the Korean Institute of Navigation
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    • v.25 no.4
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    • pp.407-415
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    • 2001
  • In the present study, irregular disturbances to ship dynamics is proposed, where irregular disturbances implying irregular wave and the fluctuating component of wind for the evaluation of automatic steering system of ship in following seas. Prediction method based on the principle of linear superposition. Irregular wave disturbances in following seas is calculated by frequency variation method. The mathematical model of each element of an automatic steering system is derived, which takes account of a few non-linear mechanisms. PD(Proportional-Derivative) controller and low-pass filter with a weather adjustment are adopted to modelling the characteristics of an autopilot. Performance index is introduced from the viewpoint of energy saving, which derived from the concept of energy loss on ship propulsion. Finally, the present methods are applied to two typical types of ship ; an ore carrier and a fishing boat. The various effects of control constants of autopilot on propulsive energy loss are investigated

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A Study on the Thermal Analysis of Induction Motors (유도 전동기의 열해석에 관한 연구)

  • Chun, Jang-Sung;Kim, Hyung-Sup;Lee, Cheol-Gyun;Won, Jong-Soo
    • Proceedings of the KIEE Conference
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    • 1993.07b
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    • pp.961-964
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    • 1993
  • The evaluation of the temperature of the motor in operation is necessary for smaller and lighter design of motors and for the determination of insulation class. The exact loss distribution modelling is absolutely necessary for the enact evaluation of the temperature. We calculated the temperature exactly by considering the loss distribution dependent on temperature. The comparison between the calculated results and the experiments is performed to verify the validity of the analysis.

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Analyzing of the Time varying failure rate of components of power distribution system using Weibull distribution (와이블 분포를 이용한 배전설비기기의 시변 고장률 분석)

  • Lee, Hee-Tae;Kim, Jae-Chul;Mon, Jong-Fil;Park, Chang-Ho
    • Proceedings of the KIEE Conference
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    • 2003.11a
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    • pp.272-274
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    • 2003
  • Distribution system reliability evaluation estimates by approach methods such as Makove modelling or Monte Carlo simulation, equation of state and failure rate that is on one basic data used to these assessment technique is described as probability of average value. because average failure rate equipment device is aged as time goes by but there is shortcoming that such used failure rate does not evaluate thing which is correct in reliability change hereafter. In this paper, failure rate displayed that apply aging to basis equipment device by passing time using Weibull distribution one of life evaluation method and for express aging of component from utility's failure database.

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Experimental Study on Subjective Evaluation of Car Interior Sound Quality (승용차 내부소음의 음질평가 실험연구)

  • 최병호;아우구스트쉬크
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.11a
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    • pp.177-182
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    • 2003
  • This study is directed toward determining the number and characteristics of psychologically meaningful perceptual dimensions required for assessing the sound Ouaiity with respect to vehicle interior and/or exterior noises. and toward identifying the acoustical or psychoacoustical bases underlying the perception. By nonmetric MDS and clustring analysis of sound quality data sets on our own, of critical importance are two perceptual dimensions for which subjective verdicts can be interpreted as loudness and sharpness. The perceptual dimensions based upon similarity judgments could be accounted for 48% and 24% of the variance. each of which might be a match for the acoustic parameter "A-weighted maximum pressure level"(r= .85) and for the psychoacoustic parameter "sharpness" (r= .65), respectively. On the other hand, the perceptual dimensions based upon preference ratings could explain 66% and 10% of the variance. where the acoustic parameter "A-weighted maximum pressure leve"(r= .92) might be taken to be a best predictor, but sharpness appeared to be less suitable for the description of Preference behavior. Linked to the results, the problems of quantitative modelling of subjective sound quality evaluation and also of implementing corresponding cognitive combination rule for technical and industrial applications, say having "winner-sound qualify" according to preference criteria will be shortly in discussion.

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Human Laughter Generation using Hybrid Generative Models

  • Mansouri, Nadia;Lachiri, Zied
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.5
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    • pp.1590-1609
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    • 2021
  • Laughter is one of the most important nonverbal sound that human generates. It is a means for expressing his emotions. The acoustic and contextual features of this specific sound are different from those of speech and many difficulties arise during their modeling process. During this work, we propose an audio laughter generation system based on unsupervised generative models: the autoencoder (AE) and its variants. This procedure is the association of three main sub-process, (1) the analysis which consist of extracting the log magnitude spectrogram from the laughter database, (2) the generative models training, (3) the synthesis stage which incorporate the involvement of an intermediate mechanism: the vocoder. To improve the synthesis quality, we suggest two hybrid models (LSTM-VAE, GRU-VAE and CNN-VAE) that combine the representation learning capacity of variational autoencoder (VAE) with the temporal modelling ability of a long short-term memory RNN (LSTM) and the CNN ability to learn invariant features. To figure out the performance of our proposed audio laughter generation process, objective evaluation (RMSE) and a perceptual audio quality test (listening test) were conducted. According to these evaluation metrics, we can show that the GRU-VAE outperforms the other VAE models.