• Title/Summary/Keyword: Model mismatch

Search Result 245, Processing Time 0.023 seconds

Novel Rate Control Scheme for Low Delay Video Coding of HEVC

  • Wu, Wei;Liu, Jiong;Feng, Lei
    • ETRI Journal
    • /
    • v.38 no.1
    • /
    • pp.185-194
    • /
    • 2016
  • In this paper, a novel rate control scheme for low delay video coding of High Efficiency Video Coding (HEVC) is proposed. The proposed scheme is developed by considering a new temporal prediction structure of HEVC. In the proposed scheme, the relationship between bit rate and quantization step is exploited firstly to formulate an accurate quadratic rate-quantization (R-Q) model. Secondly, a method of determining the quantization parameters (QPs) for the first frames within a group of pictures is proposed. Thirdly, an accurate frame-level bit allocation method is proposed for HEVC. Finally, based on the proposed R-Q model and the target bit allocated for the frame, the QPs are predicted for coding tree units by using rate-distortion (R-D) optimization. We compare our scheme against that of three other state-of-the-art rate control schemes. Experimental results show that the proposed rate control scheme can increase the Bjøntegaard delta peak signal-to-noise ratio by 0.65 dB and 0.09 dB on average compared with the JCTVC-I0094 and JCTVC-M0036 schemes, respectively, both of which have been implemented in an HEVC test model encoder; furthermore, the proposed scheme achieves a similar R-D performance to Wang's scheme, as well as obtaining the smallest bit rate mismatch error of all the schemes.

Research on residual stress in SiCf reinforced titanium matrix composites

  • Qu, Haitao;Hou, Hongliang;Zhao, Bing;Lin, Song
    • Steel and Composite Structures
    • /
    • v.17 no.2
    • /
    • pp.173-184
    • /
    • 2014
  • This study aimed to theoretical calculate the thermal residual stress in continuous SiC fiber reinforced titanium matrix composites. The analytical solution of residual stress field distribution was obtained by using coaxial cylinder model, and the numerical solution was obtained by using finite element model (FEM). Both of the above models were compared and the thermal residual stress was analyzed in the axial, hoop, radial direction. The results indicated that both the two models were feasible to theoretical calculate the thermal residual stress in continuous SiC fiber reinforced titanium matrix composites, because the deviations between the theoretical calculation results and the test results were less than 8%. In the titanium matrix composites, along with the increment of the SiC fiber volume fraction, the longitudinal property was improved, while the equivalent residual stress was not significantly changed, keeping the intensity around 600 MPa. There was a pronounced reduction of the radial residual stress in the titanium matrix composites when there was carbon coating on the surface of the SiC fiber, because carbon coating could effectively reduce the coefficient of thermal expansion mismatch between the fiber and the titanium matrix, meanwhile, the consumption of carbon coating could protect SiC fibers effectively, so as to ensure the high-performance of the composites. The support of design and optimization of composites was provided though theoretical calculation and analysis of residual stress.

Impact of Vegetation Heterogeneity on Rainfall Excess in FLO-2D Model : Yongdam Catchment (용담댐 유역에서 식생 이질성이 FLO-2D 유량 산정에 미치는 영향)

  • Song, Hojun;Lee, Khil-Ha
    • Journal of Environmental Science International
    • /
    • v.28 no.2
    • /
    • pp.259-266
    • /
    • 2019
  • Two main sources of data, meteorological data and land surface characteristics, are essential to effectively run a distributed rainfall-runoff model. The specification and averaging of the land surface characteristics in a suitable way is crucial to obtaining accurate runoff output. Recent advances in remote sensing techniques are often being used to derive better representations of these land surface characteristics. Due to the mismatch in scale between digital land cover maps and numerical grid sizes, issues related to upscaling or downscaling occur regularly. A specific method is typically selected to average and represent the land surface characteristics. This paper examines the amount of flooding by applying the FLO-2D routing model, where vegetation heterogeneity is manipulated using the Manning's roughness coefficient. Three different upscaling methods, arithmetic, dominant, and aggregation, were tested. To investigate further, the rainfall-runoff model with FLO-2D was facilitated in Yongdam catchment and heavy rainfall events during wet season were selected. The results show aggregation method provides better results, in terms of the amount of peak flow and the relative time taken to achieve it. These rwsults suggest that the aggregation method, which is a reasonably realistic description of area-averaged vegetation nature and characteristics, is more likely to occur in reality.

Evolutionary Model of Depression as an Adaptation for Blocked Social Mobility

  • Park, Hanson;Pak, Sunyoung
    • Korean Journal of Biological Psychiatry
    • /
    • v.29 no.1
    • /
    • pp.1-8
    • /
    • 2022
  • Objectives In regard to the social competition hypothesis, depression is viewed as an involuntary defeat strategy. A previous study has demonstrated that adaptation in microenvironments can result in a wide range of behavioural patterns including defense activation disorders. Using a simulation model with evolutionary ecological agents, we explore how the fitness of various defence activation traits has changed over time in different environments with high and low social mobility. Methods The Evolutionary Ecological Model of Defence Activation Disorder, which is based on the Marginal Value Theorem, was used to examine changes in relative fitness for individuals with defensive activation disorders after adjusting for social mobility. Results Our study examined the effects of social mobility on fitness by varying the d-values, a measure of depression in the model. With a decline in social mobility, the level of fitness of individuals with high levels of defense activation decreased. We gained insight into the evolutionary influence of varying levels of social mobility on individuals' degrees of depression. In the context of a highly stratified society, the results support a mismatch hypothesis which states that high levels of defence are detrimental. Conclusions Despite the fact that niche specialization in habitats composed of multiple microenvironments can result in diverse levels of defensive activation being evolutionary strategies for stability, decreased social mobility may lead to a decrease in fitness of individuals with highly activated defence modules. There may be a reason behind the epidemic of depression in modern society.

Mismatch of Perception and Data: Air Pollution, Medical Expenses, and Consumption in South Korea (관측 자료와 인지의 불일치: 대기 오염에 따른 의료 비용 및 소비 지출에 관한 분석)

  • Yun, Seong Do;Kim, Seung Gyu
    • Environmental and Resource Economics Review
    • /
    • v.29 no.2
    • /
    • pp.113-144
    • /
    • 2020
  • Throughout various data sources, it is widely observed that air quality in South Korea has become improved. Koreans, however, insist that their health status and economic burden due to worsened air quality get degenerated. This study aims to explain the mismatch between perception and measured data, air pollution-led medical expenses, and consumption behaviors in the economics perspectives. First, we demonstrated data-driven evidence of mismatch in the perceived severity of air pollution and its enhancement in measured data. Second, using the health demand model, we theoretically derived and empirically showed a co-rising relation between air pollution severity and medical expenses. Last, we analyzed that the perception led to increased defensive expenditures in consumption. This result implies the possibility of overestimation in air pollution impacts on socioeconomic losses and its possible reverse interpretation from increased social benefit after improved air quality. Our results recommend policy consideration to strengthen air quality standards, to support socially vulnerable groups regarding defensive expenditures, and to improve the accessibility and credibility of air pollution information.

Enhancement of Evoked Potential Waveform using Delay-compensated Wiener Filtering (지연보상 위너 필터링에 의한 유발전위 파형개선)

  • Lee, JeeEun;Yoo, Sun K.
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.50 no.12
    • /
    • pp.261-269
    • /
    • 2013
  • In this paper, the evoked potential(EP) was represented by additive delay model to comply with the variational noisy response of stimulus-event synchronization. The hybrid method of delay compensated-Wiener filtered-ensemble averaging(DWEA) was proposed to enhance the EP signal distortion occurred during averaging procedure due to synchronization timing mismatch. The performance of DWEA has been tested by surrogated simulation, which is composed of synthesized arbitrary delay and arbitrary level of added noise. The performance of DWEA is better than those of Wiener filtered-ensemble averaging and of conventional ensemble averaging. DWEA is endurable up to added noise gain of 7 for 10 % mean square error limit. Throughout the experimentation observation, it has been demonstrated that DWEA can be applied to enhance the evoked potential having the synchronization mismatch with added noise.

A Narrowband Detection Performance for Small Objects on Seabed by the Active Synthetic Aperture Sonar (능동 합성개구면소나에 의한 해저 소형물체 협대역 탐지 성능 고찰)

  • Kim, Boo-Il
    • Journal of the Korea Society for Simulation
    • /
    • v.23 no.4
    • /
    • pp.41-49
    • /
    • 2014
  • Detection and processing techniques for small objects on seabed by the active synthetic aperture sonar can be increased the detection performance because it can be used by short sensor array in small unmanned underwater systems that are spatially constrained. But the limited conditions on constant speed and straight movement of the platform cause a large error in the number of external environmental factors and exact phase synthesis process. In this study, analyzed the applicability of active synthetic aperture processing that is mounted on such a system, and compared detection resolution change in accordance with the phase difference mismatch caused by the along track disturbance. Various simulations were performed as a coherently focus processing model by adding along track disturbance mismatched parameter on the configuring simulator. As the result, detection performance of active synthetic processing for small objects on seabed was found a number of changes by the phase difference mismatch errors according to track disturbances and S/N ratio variations.

Sensibility Evaluation of Components of Middle and High-rise Apartment Facade in Aesthetic Old Town Districts of Kyoto - Extraction of Component Combinations Using Rough Set Theory - (쿄토시 구시가지형미관지구에서 중고층 집합주택 입면의 구성요소에 대한 감성평가 - 러프 집합을 이용한 구성요소 조합의 추출 -)

  • Shon, Dong-Hwa
    • Journal of the Korean housing association
    • /
    • v.25 no.3
    • /
    • pp.105-114
    • /
    • 2014
  • Landscape zones have been designated as aesthetic old town districts across a wide range of Nakakyo-Ku and Shimokyo-Ku, city center of Kyoto, Japan. In these districts in which traditional structures and new buildings coexist, regulations of restriction on acts such as new building's heights, shapes, materials, and colors are carried out according to local governmental landscape ordinance based on Scenic Conservation Act. And yet, minimal fulfillment of the regulations according to different designer's subjective interpretation and principle of economy is rather creating abnormal shapes not harmonized with the traditional landscape. Thus, this study aims to extract combinations between form elements of middle and high rise apartment facade that affects 'harmony' and 'mismatch' in the districts by clarifying the social rules commonly implied based on intuitive judgments (sensibility evaluation) in which human experiential knowledge is involved. As research methods, the study first analyzes the form elements of the facade through a field survey, sets up a standard model through tasks of classification and segmentation and draws computer graphic images with 99 different patterns based on it. Based on these images, this study carries out sensibility evaluation and analyzes experimental data applying the rough set theory. As a result of the analysis, the combinations of form elements that affect harmony or mismatch act greatly when the colors and shapes of the pillars, positions and the patterns of the use of the first floor are combined.

A Study of Curriculum on Vocational High School under Analysis e-Business Demand Education (e-Business Demand Education 분석에 따른 전문계고 Curriculum 연구)

  • An, Jae-Min;Park, Dea-Woo
    • Journal of the Korea Society of Computer and Information
    • /
    • v.14 no.8
    • /
    • pp.73-80
    • /
    • 2009
  • It is difficult that expertise human supply and demand for industry requires by imbalance of industry necessity human and profession organs of education's Skill Mismatch. Industry can prove productivity though reeducate school graduation person in spot and master correct technology in industry special quality. This paper is research that accommodate Demand Education that industry requires and make out full text caution Curriculum Specializing Vocational High School in e-Business field. Analysis e-Business industrial classification and occupational classification. Analysis knowledge and technological level that require in industry about e-Business education and investigate and analyze the demand. Base industry, Support industry, Apply e-Business Curriculum that is examined by practical use industry to learning, Do to estimate satisfaction about Demand Education Curriculum of industry and confirm Success special quality with research and investigation and application wave. Suggested for e-Business Curriculum's basis model in this paper and school subject Curriculum. Wish to contribute in nation development through productivity elevation through e-Business education of industry request.

A Two-stage Stochastic Programming Model for Optimal Reactive Power Dispatch with High Penetration Level of Wind Generation

  • Cui, Wei;Yan, Wei;Lee, Wei-Jen;Zhao, Xia;Ren, Zhouyang;Wang, Cong
    • Journal of Electrical Engineering and Technology
    • /
    • v.12 no.1
    • /
    • pp.53-63
    • /
    • 2017
  • The increasing of wind power penetration level presents challenges in classical optimal reactive power dispatch (ORPD) which is usually formulated as a deterministic optimization problem. This paper proposes a two-stage stochastic programming model for ORPD by considering the uncertainties of wind speed and load in a specified time interval. To avoid the excessive operation, the schedule of compensators will be determined in the first-stage while accounting for the costs of adjusting the compensators (CACs). Under uncertainty effects, on-load tap changer (OLTC) and generator in the second-stage will compensate the mismatch caused by the first-stage decision. The objective of the proposed model is to minimize the sum of CACs and the expected energy loss. The stochastic behavior is formulated by three-point estimate method (TPEM) to convert the stochastic programming into equivalent deterministic problem. A hybrid Genetic Algorithm-Interior Point Method is utilized to solve this large-scale mixed-integer nonlinear stochastic problem. Two case studies on IEEE 14-bus and IEEE 118-bus system are provided to illustrate the effectiveness of the proposed method.