• Title/Summary/Keyword: salient

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Dopamine-dependent synaptic plasticity in an amygdala inhibitory circuit controls fear memory expression

  • Lee, Joo Han;Kim, Joung-Hun
    • BMB Reports
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    • v.49 no.1
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    • pp.1-2
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    • 2016
  • Of the numerous events that occur in daily life, we readily remember salient information, but do not retain most less-salient events for a prolonged period. Although some of the episodes contain putatively emotional aspects, the information with lower saliency is rarely stored in neural circuits via an unknown mechanism. We provided substantial evidence indicating that synaptic plasticity in the dorsal ITC of amygdala allows for selective storage of salient emotional experiences, while it deters less-salient experience from entering long-term memory. After activation of D4R or weak fear conditioning, STDP stimulation induces LTD in the LA-ITC synapses. This form of LTD is dependent upon presynaptic D4R, and is likely to result from enhancement of GABA release. Both optogenetic abrogation of LTD and ablation of D4R at the dorsal ITC in vivo lead to heightened and over-generalized fear responses. Finally, we demonstrated that LTD was impaired at the dorsal ITC of PTSD model mice, which suggests that maladaptation of GABAergic signaling and the resultant LTD impairment contribute to the endophenotypes of PTSD. [BMB Reports 2016; 49(1): 1-2]

3D Mesh Model Exterior Salient Part Segmentation Using Prominent Feature Points and Marching Plane

  • Hong, Yiyu;Kim, Jongweon
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.3
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    • pp.1418-1433
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    • 2019
  • In computer graphics, 3D mesh segmentation is a challenging research field. This paper presents a 3D mesh model segmentation algorithm that focuses on removing exterior salient parts from the original 3D mesh model based on prominent feature points and marching plane. To begin with, the proposed approach uses multi-dimensional scaling to extract prominent feature points that reside on the tips of each exterior salient part of a given mesh. Subsequently, a set of planes intersect the 3D mesh; one is the marching plane, which start marching from prominent feature points. Through the marching process, local cross sections between marching plane and 3D mesh are extracted, subsequently, its corresponding area are calculated to represent local volumes of the 3D mesh model. As the boundary region of an exterior salient part generally lies on the location at which the local volume suddenly changes greatly, we can simply cut this location with the marching plane to separate this part from the mesh. We evaluated our algorithm on the Princeton Segmentation Benchmark, and the evaluation results show that our algorithm works well for some categories.

Region-based scalable self-recovery for salient-object images

  • Daneshmandpour, Navid;Danyali, Habibollah;Helfroush, Mohammad Sadegh
    • ETRI Journal
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    • v.43 no.1
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    • pp.109-119
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    • 2021
  • Self-recovery is a tamper-detection and image recovery methods based on data hiding. It generates two types of data and embeds them into the original image: authentication data for tamper detection and reference data for image recovery. In this paper, a region-based scalable self-recovery (RSS) method is proposed for salient-object images. As the images consist of two main regions, the region of interest (ROI) and the region of non-interest (RONI), the proposed method is aimed at achieving higher reconstruction quality for the ROI. Moreover, tamper tolerability is improved by using scalable recovery. In the RSS method, separate reference data are generated for the ROI and RONI. Initially, two compressed bitstreams at different rates are generated using the embedded zero-block coding source encoder. Subsequently, each bitstream is divided into several parts, which are protected through various redundancy rates, using the Reed-Solomon channel encoder. The proposed method is tested on 10 000 salient-object images from the MSRA database. The results show that the RSS method, compared to related methods, improves reconstruction quality and tamper tolerability by approximately 30% and 15%, respectively.

A group-wise attention based decoder for lightweight salient object detection on edge-devices (엣지 디바이스에서 객체 탐지를 위한 그룹별 어탠션 기반 경량 디코더 연구)

  • Thien-Thu Ngo;Md Delowar Hossain;Eui-Nam Huh
    • Proceedings of the Korea Information Processing Society Conference
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    • 2023.11a
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    • pp.30-33
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    • 2023
  • The recent scholarly focus has been directed towards the expeditious and accurate detection of salient objects, a task that poses considerable challenges for resource-limited edge devices due to the high computational demands of existing models. To mitigate this issue, some contemporary research has favored inference speed at the expense of accuracy. In an effort to reconcile the intrinsic trade-off between accuracy and computational efficiency, we present novel model for salient object detection. Our model incorporate group-wise attentive module within the decoder of the encoder-decoder framework, with the aim of minimizing computational overhead while preserving detection accuracy. Additionally, the proposed architectural design employs attention mechanisms to generate boundary information and semantic features pertinent to the salient objects. Through various experimentation across five distinct datasets, we have empirically substantiated that our proposed models achieve performance metrics comparable to those of computationally intensive state-of-the-art models, yet with a marked reduction in computational complexity.

A Salient Based Bag of Visual Word Model (SBBoVW): Improvements toward Difficult Object Recognition and Object Location in Image Retrieval

  • Mansourian, Leila;Abdullah, Muhamad Taufik;Abdullah, Lilli Nurliyana;Azman, Azreen;Mustaffa, Mas Rina
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.2
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    • pp.769-786
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    • 2016
  • Object recognition and object location have always drawn much interest. Also, recently various computational models have been designed. One of the big issues in this domain is the lack of an appropriate model for extracting important part of the picture and estimating the object place in the same environments that caused low accuracy. To solve this problem, a new Salient Based Bag of Visual Word (SBBoVW) model for object recognition and object location estimation is presented. Contributions lied in the present study are two-fold. One is to introduce a new approach, which is a Salient Based Bag of Visual Word model (SBBoVW) to recognize difficult objects that have had low accuracy in previous methods. This method integrates SIFT features of the original and salient parts of pictures and fuses them together to generate better codebooks using bag of visual word method. The second contribution is to introduce a new algorithm for finding object place based on the salient map automatically. The performance evaluation on several data sets proves that the new approach outperforms other state-of-the-arts.

A Novel Stator Hybrid Excited Doubly Salient Permanent Magnet Brushless Machine for Electric Vehicles

  • Zhu Xiaoyong;Cheng Ming
    • Journal of Electrical Engineering and Technology
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    • v.1 no.2
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    • pp.185-191
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    • 2006
  • In this paper, a novel stator hybrid excited doubly salient permanent magnet (SHEDS-PM) brushless machine with a special magnetic bridge is proposed for the first time. The originality of this machine is purposely to add a magnetic bridge in shunt with each PM pole, which not only maintains the stator lamination in its entireness, but also amplifies the effect of DC field flux on PM flux. An equivalent magnetic circuit is presented to clarify the novelty. Based on the 2-D finite element analysis, the static characteristics of the SHEDS-PM machine, namely phase flux linkage, back-EMF, cogging torque, winding inductance and static torque are deduced. The corresponding results on a prototype machine illustrate that the proposed machine is promising for application to electric vehicles.

Sensorless Control of Non-salient Permanent Magnet Synchronous Motor Drives using Rotor Position Tracking PI Controller

  • Lee Jong-Kun;Seok Jul-Ki
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • v.5B no.2
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    • pp.189-195
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    • 2005
  • This paper presents a new velocity estimation strategy for a non-salient permanent magnet synchronous motor drive without high frequency signal injection or special PWM pattern. This approach is based on the d-axis current regulator output voltage of the drive system, which contains the rotor position error information. The rotor velocity can be estimated through a rotor position tracking PI controller that controls the position error at zero. For zero and low speed operation, the PI gain of the rotor position tracking controller has a variable structure according to the estimated rotor velocity. Then, at zero speed, the rotor position and velocity have sluggish dynamics because the varying gains are very low in this region. In order to boost the bandwidth of the PI controller during zero speed, the loop recovery technique is applied to the control system. The PI tuning formulas are also derived by analyzing this control system by frequency domain specifications such as phase margin and bandwidth assignment.

Variable Selection in Clustering by Recursive Fit of Normal Distribution-based Salient Mixture Model (정규분포기반 두각 혼합모형의 순환적 적합을 이용한 군집분석에서의 변수선택)

  • Kim, Seung-Gu
    • The Korean Journal of Applied Statistics
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    • v.26 no.5
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    • pp.821-834
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    • 2013
  • Law et al. (2004) proposed a normal distribution based salient mixture model for variable selection in clustering. However, this model has substantial problems such as the unidentifiability of components an the inaccurate selection of informative variables in the case of a small cluster size. We propose an alternative method to overcome problems and demonstrate a good performance through experiments on simulated data and real data.

Unusual Motion Detection for Vision-Based Driver Assistance

  • Fu, Li-Hua;Wu, Wei-Dong;Zhang, Yu;Klette, Reinhard
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.15 no.1
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    • pp.27-34
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    • 2015
  • For a vision-based driver assistance system, unusual motion detection is one of the important means of preventing accidents. In this paper, we propose a real-time unusual-motion-detection model, which contains two stages: salient region detection and unusual motion detection. In the salient-region-detection stage, we present an improved temporal attention model. In the unusual-motion-detection stage, three kinds of factors, the speed, the motion direction, and the distance, are extracted for detecting unusual motion. A series of experimental results demonstrates the proposed method and shows the feasibility of the proposed model.

A Region-based Image Retrieval System using Salient Point Extraction and Image Segmentation (영상분할과 특징점 추출을 이용한 영역기반 영상검색 시스템)

  • 이희경;호요성
    • Journal of Broadcast Engineering
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    • v.7 no.3
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    • pp.262-270
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    • 2002
  • Although most image indexing schemes ate based on global image features, they have limited discrimination capability because they cannot capture local variations of the image. In this paper, we propose a new region-based image retrieval system that can extract important regions in the image using salient point extraction and image segmentation techniques. Our experimental results show that color and texture information in the region provide a significantly improved retrieval performances compared to the global feature extraction methods.