• Title/Summary/Keyword: Top-down mechanism

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A Review on the Models of Letter Transposition Effect and Exploration of Hangul Model (단어재인에 있어서 글자교환 효과와 한글 처리 모형 탐색)

  • Lee, Chang H.;Lee, Yoonhyoung
    • Korean Journal of Cognitive Science
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    • v.25 no.1
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    • pp.1-24
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    • 2014
  • Growing boy of studies focus on the letter transposition effect since it gives the information on how letters are coded and what variables are involved in the processes of word recognition. This review investigated various models on letter transposition effect. While most proposed models rely mainly on the bottom-up processes, evidences from various studies suggested the necessity of the top-down variables based on the cognitive processing mechanism. Especially, empirical evidences suggested that Hangul model should include a position specific processing mechanism based on onset, vowel, and coda of the Korean character.

A Knowledge-Based Machine Vision System for Automated Industrial Web Inspection

  • Cho, Tai-Hoon;Jung, Young-Kee;Cho, Hyun-Chan
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.1 no.1
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    • pp.13-23
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    • 2001
  • Most current machine vision systems for industrial inspection were developed with one specific task in mind. Hence, these systems are inflexible in the sense that they cannot easily be adapted to other applications. In this paper, a general vision system framework has been developed that can be easily adapted to a variety of industrial web inspection problems. The objective of this system is to automatically locate and identify \\\"defects\\\" on the surface of the material being inspected. This framework is designed to be robust, to be flexible, and to be as computationally simple as possible. To assure robustness this framework employs a combined strategy of top-down and bottom-up control, hierarchical defect models, and uncertain reasoning methods. To make this framework flexible, a modular Blackboard framework is employed. To minimize computational complexity the system incorporates a simple multi-thresholding segmentation scheme, a fuzzy logic focus of attention mechanism for scene analysis operations, and a partitioning if knowledge that allows concurrent parallel processing during recognition.cognition.

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Development of an Intelligent Ankle Assistive Robot (지능형 발목 근력 보조 로봇의 개발)

  • Jeong, Woo-Chul;Kim, Chang-Soon;Park, Jin-Yong;Hyun, Jung-Guen;Kim, Jung-Yup
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.6
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    • pp.538-546
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    • 2015
  • This paper describes an intelligent ankle assistive robot which provides assistive power to reduce ankle torque based on an analysis of ankle motion and muscle patterns during walking on level and sloped floors. The developed robot can assist ankle muscle power by driving an electric geared motor at the exact timing through the use of an accelerometer that detects gait phase and period, and a potentiometer to measure floor slope angle. A simple muscle assistive link mechanism is proposed to convert the motor torque into the foot assistive force. In particular, this mechanism doesn't restrain the wearer's ankle joint; hence, there is no danger of injury if the motor malfunctions. During walking, the link mechanism pushes down the top of the foot to assist the ankle torque, and it can also lift the foot by inversely driving the linkage, so this robot is useful for foot drop patients. The developed robot and control algorithm are experimentally verified through walking experiments and EMG (Electromyography) measurements.

Development on mechanism for opening sensitivity quality improvement of oven range door using nonlinear cam and spring (비선형 캠과 스프링을 이용한 오븐 렌지 도어의 열림 감성 품질 향상 메커니즘 개발)

  • Kim, Hwi-Yeon;Yun, Jae-Deuk;Jung, Yoong-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.2
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    • pp.616-624
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    • 2014
  • Most of oven range doors are opened from top to down. Feeling of door in case of home appliances including oven ranges affects the quality of product. The major factors to evaluate the feeling quality are opening force, closing force, and bouncing effect happened when the door is opened completely. If opening and closing forces become large, consumers may have complaints. If the bouncing effect becomes large, the impact can cause the body as well as the door to damage. Opening and closing forces, and bouncing effect must be minimized to improve the feeling quality. In this study, the mechanism which improves the existed dual compressive spring and cam structure is suggested by using nonlinear cam and spring. After the nonlinear cam is designed and manufactured for the suggested mechanism, this cam is confirmed to become more superior than the existed one by applying it to the practical oven range.

Benzyl Isothiocyanate-Induced Cytotoxicity via the Inhibition of Autophagy and Lysosomal Function in AGS Cells

  • Po, Wah Wah;Choi, Won Seok;Khing, Tin Myo;Lee, Ji-Yun;Lee, Jong Hyuk;Bang, Joon Seok;Min, Young Sil;Jeong, Ji Hoon;Sohn, Uy Dong
    • Biomolecules & Therapeutics
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    • v.30 no.4
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    • pp.348-359
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    • 2022
  • Gastric adenocarcinoma is among the top causes of cancer-related death and is one of the most commonly diagnosed carcinomas worldwide. Benzyl isothiocyanate (BITC) has been reported to inhibit the gastric cancer metastasis. In our previous study, BITC induced apoptosis in AGS cells. The purpose of the present study was to investigate the effect of BITC on autophagy mechanism in AGS cells. First, the AGS cells were treated with 5, 10, or 15 μM BITC for 24 h, followed by an analysis of the autophagy mechanism. The expression level of autophagy proteins involved in different steps of autophagy, such as LC3B, p62/SQSTM1, Atg5-Atg12, Beclin1, p-mTOR/mTOR ratio, and class III PI3K was measured in the BITC-treated cells. Lysosomal function was investigated using cathepsin activity and Bafilomycin A1, an autophagy degradation stage inhibitor. Methods including qPCR, western blotting, and immunocytochemistry were employed to detect the protein expression levels. Acridine orange staining and omnicathepsin assay were conducted to analyze the lysosomal function. siRNA transfection was performed to knock down the LC3B gene. BITC reduced the level of autophagy protein such as Beclin 1, class III PI3K, and Atg5-Atg12. BITC also induced lysosomal dysfunction which was shown as reducing cathepsin activity, protein level of cathepsin, and enlargement of acidic vesicle. Overall, the results showed that the BITC-induced AGS cell death mechanism also comprises the inhibition of the cytoprotective autophagy at both initiation and degradation steps.

Operational Process and Success Factors of Corporate Venture in a Chinese Company: A Case Study of Haier (중국기업의 사내벤처 운영과정과 성공요인: 하이얼(Haier) 중심으로)

  • Yu-Rou Hou;Yuan-Jing Jin;Moon-Gu Huh
    • Asia-Pacific Journal of Business
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    • v.14 no.4
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    • pp.87-113
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    • 2023
  • Purpose - Focusing on Haier, a successful corporate venture in China, we analyse the operating mechanism and success factors of corporate venture, and reveal the necessary factors for the successful implementation of corporate venture. Design/methodology/approach - This study is a single case study centred on Haier, a successful corporate venture in China. Findings - The operational process of Haier's corporate venture includes six key aspects: project selection, team building, resource allocation and support, project implementation, risk control measures, performance evaluation and rewards. In terms of success factors, the support of top management with leadership capability of value creation and sharing is very important for the success of corporate venture. Secondly, a multi reward mechanism can be introduced to motivate employees and improve performance. Thirdly, it is important to integrate corporate culture into the operating mechanism of an corporate venture. Fourthly, flexible operations that break down rigid organisational boundaries and transform the organisation into a more open platform for entrepreneurship can increase the likelihood of success. Finally, empowering employees with operational discretion can also have a positive impact on the success of an Corporate Venture. Research implications or Originality - This study contributes to theory and practice by analysing the success conditions of corporate venture, providing new understanding and drawing new perspectives, especially from the experience of Haier. The results suggest strategies and flexibility for successfully pursuing corporate venture, and provide important experience for international companies to help them gain competitive advantage in global competition. It also helps corporate leaders to promote new directions and innovations and improve their strategies to respond to dynamic environments.

Numerical Study of Fluidic Device in APR1400 Using Free-Surface Model (자유수면모델을 활용한 APR1400 유량조절장치의 수치해석 연구)

  • Lim, Sang-Gyu;You, Sung-Chang;Kim, Han-Gon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.7
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    • pp.767-774
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    • 2012
  • A fluidic device (FD) has been adopted in the safety injection tanks (SITs) of APR1400. A flow control mechanism of the FD was used to vary the flow regime in the vortex chamber corresponding to the SITs water level. The flow regime in the vortex chamber has a different pressure loss from low to high in accordance with the SITs water level. Nitrogen at the top of the SIT could be released owing to inertia of discharge flow when changing from a high flow rate to a low flow rate. This phenomenon is important to design improvement perspective because it can affect the performance of the FD. This paper shows a result of a preliminary numerical study to obtain the transient data related to air release in the flow turn-down period using a two-fluid free-surface model provided from ANSYS CFX 13.0. In conclusion, there is no significant effect on the performance of the FD, though a small quantity of air is released during the flow turn-down period.

Optimization of settlement layout based on parametric generation

  • Song, Jinghua;Xie, Xinqin;Yu, Yang
    • Advances in Computational Design
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    • v.3 no.1
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    • pp.35-47
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    • 2018
  • Design of settlement space is a complicated process while reasonable spatial layout bears great significance on the development and resource allocation of a settlement. The study proposes a weighted L-system generation algorithm based on CA (Cellular Automation) model which tags the spatial attributes of cells through changes in their state during the evolution of CA and thus identifies the spatial growth mode of a settlement. The entrance area of the Caidian Botanical and Animal Garden is used a case study for the model. A design method is proposed which starts from the internal logics of spatial generation, explores possibility of spatial rules and realizes the quantitative analysis and dynamic control of the design process. Taking a top-down approach, the design method takes into account the site information, studies the spatial generation mechanism of settlements and further presents a engine for the generation of multiple layout proposals based on different rules. A optimal solution is acquired using GA (Genetic Algorithm) which generates a settlement spatial layout carrying site information and dynamically linked to the surround environment. The study aims to propose a design method to optimize the spatial layout of the complex settlement system based on parametric generation.

Knowledge-Based Approach for an Object-Oriented Spatial Database System (지식기반 객체지향 공간 데이터베이스 시스템)

  • Kim, Yang-Hee
    • Journal of Intelligence and Information Systems
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    • v.9 no.3
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    • pp.99-115
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    • 2003
  • In this paper, we present a knowledge-based object-oriented spatial database system called KOBOS. A knowledge-based approach is introduced to the object-oriented spatial database system for data modeling and approximate query answering. For handling the structure of spatial objects and the approximate spatial operators, we propose three levels of object-oriented data model: (1) a spatial shape model; (2) a spatial object model; (3) an internal description model. We use spatial type abstraction hierarchies(STAHs) to provide the range of the approximate spatial operators. We then propose SOQL, a spatial object-oriented query language. SOQL provides an integrated mechanism for the graphical display of spatial objects and the retrieval of spatial and aspatial objects. To support an efficient hybrid query evaluation, we use the top-down spatial query processing method.

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Study on Seabed Mapping using Two Sonar Devices for AUV Application (복수의 수중 소나를 활용한 수중 로봇의 3차원 지형 맵핑에 관한 연구)

  • Joe, Hangil;Yu, Son-Cheol
    • The Journal of Korea Robotics Society
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    • v.16 no.2
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    • pp.94-102
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    • 2021
  • This study addresses a method for 3D reconstruction using acoustic data with heterogeneous sonar devices: Forward-Looking Multibeam Sonar (FLMS) and Profiling Sonar (PS). The challenges in sonar image processing are perceptual ambiguity, the loss of elevation information, and low signal to noise ratio, which are caused by the ranging and intensity-based image generation mechanism of sonars. The conventional approaches utilize additional constraints such as Lambertian reflection and redundant data at various positions, but they are vulnerable to environmental conditions. Our approach is to use two sonars that have a complementary data type. Typically, the sonars provide reliable information in the horizontal but, the loss of elevation information degrades the quality of data in the vertical. To overcome the characteristic of sonar devices, we adopt the crossed installation in such a way that the PS is laid down on its side and mounted on the top of FLMS. From the installation, FLMS scans horizontal information and PS obtains a vertical profile of the front area of AUV. For the fusion of the two sonar data, we propose the probabilistic approach. A likelihood map using geometric constraints between two sonar devices is built and a monte-carlo experiment using a derived model is conducted to extract 3D points. To verify the proposed method, we conducted a simulation and field test. As a result, a consistent seabed map was obtained. This method can be utilized for 3D seabed mapping with an AUV.