• Title/Summary/Keyword: Bottom-up Model

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A Neural Network Model for Visual Selection: Top-down mechanism of Feature Gate model (시각적 선택에 대한 신경 망 모형FeatureGate 모형의 하향식 기제)

  • 김민식
    • Korean Journal of Cognitive Science
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    • v.10 no.3
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    • pp.1-15
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    • 1999
  • Based on known physiological and psychophysical results, a neural network model for visual selection, called FeaureGate is proposed. The model consists of a hierarchy of spatial maps. and the flow of information from each level of the hierarchy to the next is controlled by attentional gates. The gates are jointly controlled by a bottom-up system favoring locations with unique features. and a top-down mechanism favoring locations with features designated as target features. The present study focuses on the top-down mechanism of the FeatureGate model that produces results similar to Moran and Desimone's (1985), which many current models have failed to explain, The FeatureGate model allows a consistent interpretation of many different experimental results in visual attention. including parallel feature searches and serial conjunction searches. attentional gradients triggered by cuing, feature-driven spatial selection, split a attention, inhibition of distractor locations, and flanking inhibition. This framework can be extended to produce a model of shape recognition using upper-level units that respond to configurations of features.

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Numerical Model on Suspended Load Diffusion due to Tidal Flow (조류(潮流)에 의한 부유사(浮遊砂)의 확산(擴散)에 대한 수치모형(數値模型))

  • Lee, Jong Kyu;Ahn, Soo Hahn
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.4 no.4
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    • pp.13-23
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    • 1984
  • The purpose of this paper is to develop a numerical model which can be used to compute the suspended load concentration of which the two-dimensional unsteady diffusion equation is able to be solved by the finite difference method using the implicit scheme. The pick-up rate formula from the bottom used in the open channel as a sink source term and the Coleman's empirical formula for the diffusion coefficient were taken, and especially the hindered settling velocity and the vertical velocity of flow due to the periodical tidal motion were taken into account, while the effects of the variables, such as the horizontal and vertical velocities of flow, tidal range, the settling velocity and hindered settling, on the suspened load concentrations have been discussed, comparing the results obtained from the different cases in the simulation conditions.

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The Extraction of Car-Licence Plates using Combined Color Information of HSI and YIQ (HSI와 YIQ의 복합 색상정보를 이용한 차량 번호판 영역 추출)

  • Lee, Hwa-Jin;Park, Hyung-Chul;Jun, Byung-Hwan
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.12
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    • pp.3995-4003
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    • 2000
  • This paper describes a method that extracts the region of car-licence plates in color images of private and commercial cars. To extract car-licence plates, we use the feature that car-licence plate regions have regular colors according to the kinds of cars. In this paper, we propose the method that combines H component of HSI color model and Q component of YIQ color model. To improve efficiency of the process, we cxplore lines ill a car image by a regular interval in a bottom-up style. As a result, the extraction rates by only H-component. only by Q- component. and by combined Hand Q, are 53.6%, 82.1%, and 94.6% respectively.

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A Study on the Mapping Guideline of IDEF for UMM Adaptation (UMM 적용을 위한 IDEF 매핑 방법에 대한 연구)

  • Shin Kitae;Park Chankwon;Sim Eoksu;Kim Eungab
    • Korean Management Science Review
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    • v.21 no.2
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    • pp.61-77
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    • 2004
  • As various methodologies for business process analysis and design have been conducted in many organizations by their own ways, those methodologies are not compatible each other. In order to reduce the cost of analysis for organizations. some mapping methods between different methodologies need to be developed. UMM(UN/CEFACT Modeling Methodology) that has an object-oriented point of view. can overcome the limits of existing bottom-up approaches and make it reasonable. It also simplifies the business and administrative procedures. IDEF( Integrated Definition Language) with a structural point of view that has been widely used as a system analysis and design method, needs to be mapped to UMM in order to reuse the existing IDEF models. In this study, we propose a guideline that deals with procedures of utilizing IDEF models from which we want to derive the UMM models for developing an electronic commerce system including electronic documents exchange. By comparing IDEF and UMM, we analyze the differences between those two methodologies. Based on these differences. we suggest the basic strategies for mapping method from IDEF to UMM. We also propose a mapping guideline that can make UMM results from the modeling results of IDEF. We can take an advantage of the existing IDEF analysis design results when we adopt UMM methodology for electronic business system. Many analysts who are familiar with the IDEF methodology can develop UMM work-flow by utilizing their existing results and skills.

The Chinese Black Box - A Scientific Model of Traditional Chinese Medicine

  • Theodorou, Matthias;Fleckenstein, Johannes
    • Journal of Acupuncture Research
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    • v.36 no.1
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    • pp.1-11
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    • 2019
  • Models of traditional Chinese medicine (TCM) are still difficult to grasp from the view of a Western-cultural background. For proper integration into science and clinical research, it is vital to think "out of the box" of classical sciences. Modern sciences, such as quantum physics, system theory, and information theory offer new models, that reveal TCM as a method to process information. For this purpose, we apply concepts of information theory to propose a "Chinese black box model," that allows for a non-deterministic, bottom-up approach. Considering a patient as an undeterminable complex system, the process of getting information about an individual in Chinese diagnostics is compared to the input-process-output principle of information theory and quantum physics, which is further illustrated by Wheeler's "surprise 20 questions." In TCM, an observer uses a decision-making algorithm to qualify diagnostic information by the binary polarities of "yang" (latin activity) and "yin" (latin structivity) according to the so called "8 principles" (latin 8 guiding criteria). A systematic reconstruction of ancient Chinese terms and concepts illuminates a scattered scientific method, which is specified in a medical context by Latin terminology of the sinologist Porkert [definitions of the Latin terms are presented in Porkert's appendix [1] (cf. Limitations)].

A Study on a Facet-Based Ontology Design for Archival Records of Finding Dispersed Families (이산가족 찾기 기록 패싯 기반 온톨로지 모델 설계에 관한 연구)

  • Lee, Eun Uk;Park, Heejin
    • Journal of Korean Society of Archives and Records Management
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    • v.18 no.4
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    • pp.231-257
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    • 2018
  • This paper aims to suggest a facet-based ontology model that can help sort and access records of dispersed families to address these problems. The facet systematically defines the categories of target concepts, which can create diverse and multiple access points. Using the top-down and bottom-up approaches, the facets, which consist of five upper classes and 18 lower classes, were derived for the records of dispersed families. The proposed ontology model was evaluated by real users. The results show that, overall, the ontology is complete and relevant in terms of access points, availability of context information of the records, and description elements for search and use of the records on dispersed families.

A Multimodal Fusion Method Based on a Rotation Invariant Hierarchical Model for Finger-based Recognition

  • Zhong, Zhen;Gao, Wanlin;Wang, Minjuan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.1
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    • pp.131-146
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    • 2021
  • Multimodal biometric-based recognition has been an active topic because of its higher convenience in recent years. Due to high user convenience of finger, finger-based personal identification has been widely used in practice. Hence, taking Finger-Print (FP), Finger-Vein (FV) and Finger-Knuckle-Print (FKP) as the ingredients of characteristic, their feature representation were helpful for improving the universality and reliability in identification. To usefully fuse the multimodal finger-features together, a new robust representation algorithm was proposed based on hierarchical model. Firstly, to obtain more robust features, the feature maps were obtained by Gabor magnitude feature coding and then described by Local Binary Pattern (LBP). Secondly, the LGBP-based feature maps were processed hierarchically in bottom-up mode by variable rectangle and circle granules, respectively. Finally, the intension of each granule was represented by Local-invariant Gray Features (LGFs) and called Hierarchical Local-Gabor-based Gray Invariant Features (HLGGIFs). Experiment results revealed that the proposed algorithm is capable of improving rotation variation of finger-pose, and achieving lower Equal Error Rate (EER) in our homemade database.

Wind load parameters and performance of an integral steel platform scaffold system

  • Zhenyu Yang;Qiang Xie;Yue Li;Chang He
    • Wind and Structures
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    • v.36 no.4
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    • pp.263-275
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    • 2023
  • As a new kind of construction facility for high rise buildings, the integral steel platform scaffold system (ISPS) consisting of the steel skeleton and suspended scaffold faces high wind during the construction procedure. The lattice structure type and existence of core tubes both make it difficult to estimate the wind load and calculate the wind-induced responses. In this study, an aeroelastic model with a geometry scale ratio of 1:25 based on the ISPS for Shanghai Tower, with the representative square profile, is manufactured and then tested in a wind tunnel. The first mode of the prototype ISPS is a torsional one with a frequency of only 0.68 Hz, and the model survives under extreme wind speed up to 50 m/s. The static wind load and wind vibration factors are derived based on the test result and supplementary finite element analysis, offering a reference for the following ISPS design. The spacer at the bottom of the suspended scaffold is suggested to be long enough to touch the core tube in the initial status to prevent the collision. Besides, aerodynamic wind loads and cross-wind loads are suggested to be included in the structural design of the ISPS.

Cross-cultural Studies Revisited in International Business (국제비즈니스에서 비교문화 연구의 재검토)

  • Cho, Ho-Hyeon
    • Iberoamérica
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    • v.12 no.1
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    • pp.407-439
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    • 2010
  • Growth of researches addressing cross-culture in international business is exponential. This article reviews the extant researches around the national culture and describes the various conceptualization of culture through discussion of some of popular models of national culture. This article presented some of the most important issues in international business surrounding globalization, especially convergence and divergence of cultures and cultural changes. Global rapid changes in international business environment request the reconsideration of the assumption of cultural stability and the simple view of culture, which tends to examine the static influence of a few cultural factors in isolation form other cultural factors and contextual elements. This paper identifies a valid cultural grouping and proposes the following typology of the possible methodologies in international business; Ethnological description, Use of proxies, Direct values inference, and Indirect values inference. Rather than selecting a single methodology, it appears to be more appropriate to use multi-method in the cross-cultural international business research. It has been shown that cultural change is intertwined with socioeconomic-institutional variables, and that these variables may also add to determine culture contemporarily. This paper also explained the dynamics of culture as multi-level, multi-layer constructs. According to this model, we may understand how the dynamic nature of culture conveys the top-down-bottom-up processes where one cultural level affects changes in other level of culture.

Modeling the Visual Target Search in Natural Scenes

  • Park, Daecheol;Myung, Rohae;Kim, Sang-Hyeob;Jang, Eun-Hye;Park, Byoung-Jun
    • Journal of the Ergonomics Society of Korea
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    • v.31 no.6
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    • pp.705-713
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    • 2012
  • Objective: The aim of this study is to predict human visual target search using ACT-R cognitive architecture in real scene images. Background: Human uses both the method of bottom-up and top-down process at the same time using characteristics of image itself and knowledge about images. Modeling of human visual search also needs to include both processes. Method: In this study, visual target object search performance in real scene images was analyzed comparing experimental data and result of ACT-R model. 10 students participated in this experiment and the model was simulated ten times. This experiment was conducted in two conditions, indoor images and outdoor images. The ACT-R model considering the first saccade region through calculating the saliency map and spatial layout was established. Proposed model in this study used the guide of visual search and adopted visual search strategies according to the guide. Results: In the analysis results, no significant difference on performance time between model prediction and empirical data was found. Conclusion: The proposed ACT-R model is able to predict the human visual search process in real scene images using salience map and spatial layout. Application: This study is useful in conducting model-based evaluation in visual search, particularly in real images. Also, this study is able to adopt in diverse image processing program such as helper of the visually impaired.