• Title/Summary/Keyword: attention mechanism

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The effects of endogenous attention and reorienting on performance of detection task (내현적 주의와 재정향이 탐지과제 수행에 미치는 영향)

  • Ko, Jae-Hyeong;Kim, Shin-Woo;Li, Hyung-Chul O.
    • Science of Emotion and Sensibility
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    • v.15 no.1
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    • pp.37-46
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    • 2012
  • We tested the effects of endogenous attention and reorienting on the performance of detection task. In the classic detection paradigm of Posner and Cohen (1980), performance on target detection is measured, where target appears either on the same or difference spatial location of cue stimulus after brief period of SOA (stimulus onset asynchrony). In this study, we induced exogenous attention by manipulating predictability of cue for target, and also induced reorientation by inserting additional (reorienting) cue between initial cue and target. Experiment 1 had three conditions of reorienting speed: Early, middle, and late. Facilitation and IOR (inhibition of return) occurred in different forms depending on SOA and reorienting speed, but we were not able to discover interpretable pattern in the results. However, reanalysis of early reorienting condition revealed that facilitation and IOR occurred in a crossed manner where short SOA found facilitation and long SOA did IOR, the typical results of simple detection task. Experiment 2 collected additional data to replicate the results in early reorienting condition of experiment 1. The results obtained that facilitation occurred with short SOA and IOR with long SOA. These results contrast with those of Wright and Richard (2000) where they reported elimination of IOR when cue had predictability of target locations. These results suggest that additional cue (here, orienting cue), which rapidly appears before extinction of IOR by prior cue, brings about double IOR. The present research demonstrates that even when attention is allocated to certain location via endogenous mechanism, rapidly repeating cues in certain location maximizes IOR that offsets the effects of endogenous attention to the same location.

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Development of a 2-DOF Ankle Mechanism for Gait Rehabilitation Robots (보행 재활 로봇을 위한 2자유도 족관절 기구 개발)

  • Heo, Geun Sub;Kang, Oh Hyun;Lee, Sang Ryong;Lee, Choon-Young
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.6
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    • pp.503-509
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    • 2015
  • In this paper, we designed and tested an ankle joint mechanism for a gait rehabilitation robot. Gait rehabilitation programs are designed to improve the natural leg motion of patients who have lost their walking capabilities by accident or disease. Strengthening the muscles of the lower-limbs and stimulation of the nervous system corresponding to walking helps patients to walk again using gait assistive devices. It is an obvious requirement that the rehabilitation system's motion should be similar to and as natural as the normal gait. However, the system being used for gait rehabilitation does not pay much attention to ankle joints, which play an important role in correct walking as the motion of the ankle should reflect the movement of the center of gravity (COG) of the body. Consequently, we have designed an ankle mechanism that ensures the safety of the patient as well as efficient gait training. Also, even patients with low leg muscle strength are able to operate the ankle joint due to the direct-drive mechanism without a reducer. This safety feature prevents any possible adverse load on the human ankle. The additional degree of freedom for the roll motion achieves a gait pattern which is similar to the normal gait and with a greater degree of comfort.

Exploration of growth mechanism for layer controllable graphene on copper

  • Song, Woo-Seok;Kim, Yoo-Seok;Kim, Soo-Youn;Kim, Sung-Hwan;Jung, Dae-Sung;Jun, Woo-Sung;Jeon, Cheol-Ho;Park, Chong-Yun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.490-490
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    • 2011
  • Graphene, hexagonal network of carbon atoms forming a one-atom thick planar sheet, has been emerged as a fascinating material for future nanoelectronics. Huge attention has been captured by its extraordinary electronic properties, such as bipolar conductance, half integer quantum Hall effect at room temperature, ballistic transport over ${\sim}0.4{\mu}m$ length and extremely high carrier mobility at room temperature. Several approaches have been developed to produce graphene, such as micromechanical cleavage of highly ordered pyrolytic graphite using adhesive tape, chemical reduction of exfoliated graphite oxide, epitaxial growth of graphene on SiC and single crystalline metal substrate, and chemical vapor deposition (CVD) synthesis. In particular, direct synthesis of graphene using metal catalytic substrate in CVD process provides a new way to large-scale production of graphene film for realization of graphene-based electronics. In this method, metal catalytic substrates including Ni and Cu have been used for CVD synthesis of graphene. There are two proposed mechanism of graphene synthesis: carbon diffusion and precipitation for graphene synthesized on Ni, and surface adsorption for graphene synthesized on Cu, namely, self-limiting growth mechanism, which can be divided by difference of carbon solubility of the metals. Here we present that large area, uniform, and layer controllable graphene synthesized on Cu catalytic substrate is achieved by acetylene-assisted CVD. The number of graphene layer can be simply controlled by adjusting acetylene injection time, verified by Raman spectroscopy. Structural features and full details of mechanism for the growth of layer controllable graphene on Cu were systematically explored by transmission electron microscopy, atomic force microscopy, and secondary ion mass spectroscopy.

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Layered Video Quality Incentive Mechanism for Peer-to-Peer Video Streaming (P2P (Peer-to-Peer) 비디오 스트리밍을 위한 다중 비디오 품질 인센티브 기법)

  • Wibowo, Budiono;Kwon, Jin-Baek
    • The KIPS Transactions:PartB
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    • v.17B no.3
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    • pp.189-196
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    • 2010
  • Peer-to-Peer (P2P) has attracted attention as an alternative way to enable streaming videos on the Internet. Although P2P systems depend on bandwidth contribution from peers, peers are likely to refuse to contribute their bandwidth. In this paper, we proposed a P2P streaming system that encourages peers to contribute their upstream bandwidth by maintaining fairness among peers and providing different video quality between cooperative peers and selfish peers with a manageable way. Our proposed system determines if peers are cooperative or selfish by a rating mechanism based on their contributed upstream bandwidth, and offers a high quality video to cooperative peers as an incentive. Also we propose a tree reconstruction algorithm to make the system work effectively. Through simulation, we show that the tree reconstruction algorithm works effectively, and our incentive mechanism allocates more downstream bandwidth to cooperative peers and punished selfish peers with low quality video.

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

  • Kim, Min Sik
    • Korean Journal of Cognitive Science
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    • v.10 no.3
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    • pp.1.2-1.2
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    • 1999
  • 시각적 선택에 대한 과거 정신물리학적, 신경 생리학적 연구결과를 토대로 Feature Gate 라는 신경 망 모형을 제안하였다. 이 모형에는 공간 배치도가 위계 적으로 구성되어 있으며, 정보의 흐름이 위계의 각 수준으로부터 그 다음 수준으로 넘어갈 때 주의 게이트에 의해 조절되도록 되어 있다. 주의 게이트들은 독특한 세부 특징을 가진 위치에 반응하는 상향식 시스템과 표적 세부 특징이 있는 위치에 반응하는 하향식 기제 모두에 의해 조절된다. 본 연구는 Feature Gate 모형의 하향식 기제에 초점을 맞추어 모형을 설명하고, 현재 다른 모형들이 설명하지 못하는 Moran & Desimone(1985)의 연구결과를 이 모형이 어떻게 설명하는지를 제시하고자 한다. Feature Gate 모형은 병렬 적인 세부특징 검색, 계열 적 접합표적 검색, 단서에 의한 주의의 점진적 감소 모형, 세부특징-주도적인 공간적 선택, 주의의 분할, 방해자극 위치의 억제, 주변 억제 등을 포함한 시각적 주의 연구의 여러 가지 많은 현상들을 설명하는데 하나의 일관적인 해석을 제공해 준다. 앞으로 이 모형을 더욱 확장, 발전 시켜 세부특징의 조합된 배열에 반응하는 상위 수준의 유닛을 사용한다면 시각적 선택과정이 포함된 형태 재인 모형으로 개발될 수 있다.

Performance evaluation of different strengthening measures for exterior RC beam-column joints under opening moments

  • Dar, M. Adil;Subramanian, N.;Pande, Sumeet;Dar, A.R.;Raju, J.
    • Structural Engineering and Mechanics
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    • v.74 no.2
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    • pp.243-254
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    • 2020
  • Devastating RC structural failures in the past have identified that the behavior of beam-column joints is more critical and significantly governs the global structural response under seismic loading. The congestion of reinforcement at the beam-column joints with other constructional difficulties has escalated the attention required for strengthening RC beam-column joints. In this context, numerous studies have been carried out in the past, which mainly focused on jacketing the joints with different materials. However, there is no comparative study of different approaches used to strengthen RC beam-column joints, from efficiency and cost perspective. This paper presents a detailed investigation carried out to study the various strengthening schemes of exterior RC beam-column joints, viz., steel fiber reinforcement, carbon fiber reinforced polymer (CFRP) strengthening, steel haunch strengthening, and confining joint reinforcement. The effectiveness of each scheme was evaluated experimentally. These specimens were tested under horizontal loading that produced opening moments on the joints and their behavior was studied with emphasis on strength, displacement ductility, stiffness, and failure mechanism. Special attention was given to the study of crack-width.

The Effect on the Granodiorite Suspension Coated Indoor Finishing Materials for Reduction of TVOC Emissions (실내 마감재료의 TVOC 방출 저감을 위한 화강섬록암 현탁액 도포효과)

  • Lee, Jong-Gyu;Kim, Ji-Hyun;Lee, Jae-Yong;Lee, Soo-Yong
    • Journal of the Korea Institute of Building Construction
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    • v.8 no.5
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    • pp.93-99
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    • 2008
  • The environment draws attention in the global community and a growing number of Koreans have interest in improving the quality of life, the importance of house environment has attracted the attention of the public. Against this backdrop, constructors have unveiled environmentally -friendly projects. However, they failed to establish people-oriented environment by being occupied with maximizing profitability through the improvement of brand image and caused sick house syndrome that has recently made controversy. In this regard, the study analyzed the mechanism of discharge of TVOC, one of the sick house syndrome-causing materials, that affects IAQ and its characteristics and examined the effect that granodiorite has on reduction of the discharge of TVOC in order to minimize damage. Experimental sample consisted of interior finishing materials frequently used in ceiling, wall and floor and adhesives used at a time of construction, and the TVOC of building materials was measured through the use of septum bottle unlike In the existing chamber method. Measures to counter the sick house syndrome were suggested by reducing the possible damage from the stage of selection of building material and by figuring out the effect that the granodiorite has on reduction of the discharge of TVOC.

The Study on People's Satisfaction towards Public Services of Viet Nam: Evidence of Tra Vinh Provincial Center of Public Administrative Services

  • NGUYEN, Ha Hong
    • The Journal of Asian Finance, Economics and Business
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    • v.6 no.2
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    • pp.183-187
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    • 2019
  • The paper aims to provide some recommendations to improve the operational capacity of the Tra Vinh Provincial Center of Public Administrative Services and to improve the effectiveness and efficiency of management in the State administrative agencies. The study on people's satisfaction towards public services of Tra Vinh Provincial Center of Public Administrative Services was conducted by collecting primary data of 300 people who used public services provided by this Center from September 2018 to November 2018. By using the multivariate regression method, the author found that there were a number of factors affecting people's satisfaction towards public services at the Center, including procedures, service fee, and attitudes of the staff, empathy, staff capacity, and trust. These factors had an impact on people's satisfaction towards public administrative services performed by staff officers from Tra Vinh Provincial Center of Public Administrative Services. Since then, the study has proposed policy implications to improve people's satisfaction on service quality at the Center such as: Develop a flexible charge mechanism of public services; Enhance the sense of responsibility of staff officers; Pay attention to improving administrative procedures; Establish trustworthiness to people; Pay attention to professional improvement; and Build up a friendly and respectful team of staff.

A Study on Improved Comments Generation Using Transformer (트랜스포머를 이용한 향상된 댓글 생성에 관한 연구)

  • Seong, So-yun;Choi, Jae-yong;Kim, Kyoung-chul
    • Journal of Korea Game Society
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    • v.19 no.5
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    • pp.103-114
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    • 2019
  • We have been studying a deep-learning program that can communicate with other users in online communities since 2017. But there were problems with processing a Korean data set because of Korean characteristics. Also, low usage of GPUs of RNN models was a problem too. In this study, as Natural Language Processing models are improved, we aim to make better results using these improved models. To archive this, we use a Transformer model which includes Self-Attention mechanism. Also we use MeCab, korean morphological analyzer, to address a problem with processing korean words.

Zero-anaphora resolution in Korean based on deep language representation model: BERT

  • Kim, Youngtae;Ra, Dongyul;Lim, Soojong
    • ETRI Journal
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    • v.43 no.2
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    • pp.299-312
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    • 2021
  • It is necessary to achieve high performance in the task of zero anaphora resolution (ZAR) for completely understanding the texts in Korean, Japanese, Chinese, and various other languages. Deep-learning-based models are being employed for building ZAR systems, owing to the success of deep learning in the recent years. However, the objective of building a high-quality ZAR system is far from being achieved even using these models. To enhance the current ZAR techniques, we fine-tuned a pretrained bidirectional encoder representations from transformers (BERT). Notably, BERT is a general language representation model that enables systems to utilize deep bidirectional contextual information in a natural language text. It extensively exploits the attention mechanism based upon the sequence-transduction model Transformer. In our model, classification is simultaneously performed for all the words in the input word sequence to decide whether each word can be an antecedent. We seek end-to-end learning by disallowing any use of hand-crafted or dependency-parsing features. Experimental results show that compared with other models, our approach can significantly improve the performance of ZAR.