• 제목/요약/키워드: Virtual Threshold

검색결과 69건 처리시간 0.024초

Virtual Screening Approaches in Identification of Bioactive Compounds Akin to Delphinidin as Potential HER2 Inhibitors for the Treatment of Breast Cancer

  • Patidar, Kavisha;Deshmukh, Aruna;Bandaru, Srinivas;Lakkaraju, Chandana;Girdhar, Amandeep;Gutlapalli, VR;Banerjee, Tushar;Nayarisseri, Anuraj;Singh, Sanjeev Kumar
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권4호
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    • pp.2291-2295
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    • 2016
  • Small molecule tyrosine kinase inhibitors targeting HER 2 receptors have emerged as an important therapeutic approach in inhibition of downstream proliferation and survival signals for the treatment of breast cancers. Recent drug discovery efforts have demonstrated that naturally occurring polyphenolic compounds like delphinidin have potential to inhibit proliferation and promote apoptosis of breast cancer cells by targeting HER2 receptors. While delphinidin may thus reduce tumour size, it is associated with serious side effects like dysphonia. Owing to the narrow therapeutic window of delphinidin, the present study aimed to identify high affinity compounds targeting HER2 with safer pharmacological profiles than delphinidin through virtual screening approaches. Delphinidin served as the query parent for identification of structurally similar compounds by Tanimoto-based similarity searching with a threshold of 95% against the PubChem database. The compounds retrieved were further subjected to Lipinski and Verber's filters to obtain drug like agents, then further filtered by diversity based screens with a cut off of 0.6. The compound with Pubchem ID: 91596862 was identified to have higher affinity than its parent. In addition it also proved to be non-toxic with a better ADMET profile and higher kinase activity. The compound identified in the study can be put to further in vitro drug testing to complement the present study.

Virtual Ground Based Augmentation System

  • Core, Giuseppe Del;Gaglione, Salvatore;Vultaggio, Mario;Pacifico, Armando
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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    • pp.33-37
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    • 2006
  • Since 1993, the civil aviation community through RTCA (Radio Technical Commission for Aeronautics) and the ICAO (International Civil Air Navigation Organization) have been working on the definition of GNSS augmentation systems that will provide improved levels of accuracy and integrity. These augmentation systems have been classified into three distinct groups: Aircraft Based Augmentation Systems (ABAS), Space Based Augmentation Systems (SBAS) and Ground Based Augmentation Systems (GBAS). The last one is an implemented system to support Air Navigation in CAT-I approaching operation. It consists of three primary subsystems: the GNSS Satellite subsystem that produces the ranging signals and navigation messages; the GBAS ground subsystem, which uses two or more GNSS receivers. It collects pseudo ranges for all GNSS satellites in view and computes and broadcasts differential corrections and integrity-related information; the Aircraft subsystem. Within the area of coverage of the ground station, aircraft subsystems may use the broadcast corrections to compute their own measurements in line with the differential principle. After selection of the desired FAS for the landing runway, the differentially corrected position is used to generate navigation guidance signals. Those are lateral and vertical deviations as well as distance to the threshold crossing point of the selected FAS and integrity flags. The Department of Applied Science in Naples has create for its study a virtual GBAS Ground station. Starting from three GPS double frequency receivers, we collect data of 24h measures session and in post processing we generate the GC (GBAS Correction). For this goal we use the software Pegasus V4.1 developed from EUROCONTROL. Generating the GC we have the possibility to study and monitor GBAS performance and integrity starting from a virtual functional architecture. The latter allows us to collect data without the necessity to found us authorization for the access to restricted area in airport where there is one GBAS installation.

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VR 애플리케이션을 위한 사물인터넷 기반 어지럼증 검출 시스템 개발 (Development of an IoT-Based Dizziness Detection System for VR Applications)

  • 고은이;김영천;박혜리;정원석;서정욱
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2019년도 춘계학술대회
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    • pp.423-425
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    • 2019
  • 사용자가 HMD(Head Mounted Display) 기기를 착용하고 VR(Virtual Reality) 애플리케이션을 체험하다보면 사이버 멀미(Cybersickness)를 경험하게 된다. 사이버 멀미의 원인은 아직 불명확 하지만 주로 눈으로 들어오는 시각 정보와 전정기관(이동과 평형감각을 주관하는 감각 기관)에 들어오는 감각 정보가 불일치할 때 발생하는 것으로 알려져 있다. 그러나 사이버 멀미를 측정하기 위한 데이터 수집 및 분석시스템 개발에 대한 연구는 부족한 상태이다. 따라서 본 논문에서는 사물인터넷 플랫폼으로 VR HMD 기기를 착용한 사용자로부터 뇌파와 생체 데이터를 수집하고, 결정 문턱값으로 사이버 멀미가 유발하는 어지럼증을 판별하는 시스템을 설계한다. 14명 실험 참여자를 고려하여 어지럼증 검출 성능을 평가한 결과, 약 92% 정확도를 나타내었다.

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Robust Multithreaded Object Tracker through Occlusions for Spatial Augmented Reality

  • Lee, Ahyun;Jang, Insung
    • ETRI Journal
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    • 제40권2호
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    • pp.246-256
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    • 2018
  • A spatial augmented reality (SAR) system enables a virtual image to be projected onto the surface of a real-world object and the user to intuitively control the image using a tangible interface. However, occlusions frequently occur, such as a sudden change in the lighting environment or the generation of obstacles. We propose a robust object tracker based on a multithreaded system, which can track an object robustly through occlusions. Our multithreaded tracker is divided into two threads: the detection thread detects distinctive features in a frame-to-frame manner, and the tracking thread tracks features periodically using an optical-flow-based tracking method. Consequently, although the speed of the detection thread is considerably slow, we achieve real-time performance owing to the multithreaded configuration. Moreover, the proposed outlier filtering automatically updates a random sample consensus distance threshold for eliminating outliers according to environmental changes. Experimental results show that our approach tracks an object robustly in real-time in an SAR environment where there are frequent occlusions occurring from augmented projection images.

Power-Gating Structure with Virtual Power-Rail Monitoring Mechanism

  • Lee, Hyoung-Wook;Lee, Hyun-Joong;Woo, Jong-Kwan;Shin, Woo-Yeol;Kim, Su-Hwan
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제8권2호
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    • pp.134-138
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    • 2008
  • We present a power gating turn-on mechanism that digitally suppresses ground-bounce noise in ultra-deep submicron technology. Initially, a portion of the sleep transistors are switched on in a pseudo-random manner and then they are all turned on fully when VVDD is above a certain reference voltage. Experimental results from a realistic test circuit designed in 65nm bulk CMOS technology show the potential of our approach.

A study on the classifying vehicles for traffic flow analysis using LiDAR DATA

  • Heo J.Y.;Choi J.W.;Kim Y.I.;Yu K.Y.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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    • pp.633-636
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    • 2004
  • Airborne laser scanning thechnology has been studied in many applications, DSM(Digital Surface Model) development, building extraction, 3D virtual city modeling. In this paper, we will evaluate the possibility of airborne laser scanning technology for transportation application, especially for recognizing moving vehicles on road. First, we initially segment the region of roads from all LiDAR DATA using the GIS map and intensity image. Secondly, the segmented region is divided into the roads and vehicles using the height threshold value of local based window. Finally, the vehicles will be classified into the several types of vehicles by MDC(Minimum Distance Classification) method using the vehicle's geometry information, height, length, width, etc

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RECONSTRUCT10N AND NAVIGATION OF CYLINDRICAL OBJECTS FROM MEDICAL IMAGES

  • Park, Yoo-Joo;Kim, Myoung-Hee;Min, Kyung-Ha
    • 한국시뮬레이션학회:학술대회논문집
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    • 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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    • pp.223-230
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    • 2001
  • This paper proposes a new contour detection method and adaptive reconstruction scheme for the cylindrical organs, such as blood vessels or arteries. Furthermore, we present java-based navigation controller which has been built to examine the inside of cylindrical objects. Tn the preprocessing procedure, a few preprocessing image filters are applied in order to remove unwanted artifacts from the medical images and to estimate threshold values for the object of interest. We define a context-free grammar, which is proper fur properties of contours of cylindrical objects. In the next procedure, we extract contours using advanced radial gradient method and represent contours as context-free grammar derivation trees. We build polygons between two contours efficiently by traversing the derivations trees of the contours. We fly through the reconstructed virtual models using java-based navigation controller and VRML viewer.

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진동식 촉각 자극에 대한 손의 상대적 민감도 반응 (Human Sensitivity Responses to Vibrotactile Stimulation on the Hand : Measurement of Differential Thresholds)

  • 이성일
    • 대한인간공학회지
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    • 제18권3호
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    • pp.1-12
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    • 1999
  • This study investigated human operator's perceptual and psychophysical responses to vibrotactile stimulation on various parts of the hand. Using a small vibrotactile display, the effects of three mechanical parameters consisting vibrotactile stimulations, i.e., vibration frequency, pulse-width modulation duty cycle, and number of contactors, on differential thresholds were examined at five different loci of the hand. It was observed that differential threshold varies with vibration frequency and number of active contactors. Differential sensitivity was the greatest at the vibration frequency of 120 Hz. The differential sensitivity was not found to be affected by loci on the hand. The area of stimulation on the hand was also found to be significant in that the sensitivity increased with the number of active contactors. It should be noted that the conclusions from this study generally correspond to those from the previous study on the absolute sensitivity. which means that tactile sensitivity to vibrotactile stimulations can be controlled with a systematic and consistent passion for emulating normal everyday contact on human hands in teleoperation and virtual reality applications.

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Multimodal Curvature Discrimination of 3D Objects

  • Kim, Kwang-Taek;Lee, Hyuk-Soo
    • 융합신호처리학회논문지
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    • 제14권4호
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    • pp.212-216
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    • 2013
  • As virtual reality technologies are advanced rapidly, how to render 3D objects across modalities is becoming an important issue. This study is therefore aimed to investigate human discriminability on the curvature of 3D polygonal surfaces with focusing on the vision and touch senses because they are most dominant when explore 3D shapes. For the study, we designed a psychophysical experiment using signal detection theory to determine curvature discrimination for three conditions: haptic only, visual only, and both haptic and visual. The results show that there is no statistically significant difference among the conditions although the threshold in the haptic condition is the lowest. The results also indicate that rendering using both visual and haptic channels could degrade the performance of discrimination on a 3D global shape. These results must be considered when a multimodal rendering system is designed in near future.

모바일 기기 진동의 인지적 특성 (Perceptual Characteristics of Mobile Device Vibrations)

  • 최승문
    • 한국HCI학회:학술대회논문집
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    • 한국HCI학회 2008년도 학술대회 3부
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    • pp.30-35
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    • 2008
  • 본 논문은 2008 한국 HCI 학회 중 개최되는 햅틱스 관련 연구 워크샵에 "모바일 기기 진동의 인지적 특성" 이라는 제목으로 발표하기 위하여, 포항공과대학교 햅틱스 및 가상현실 연구실에서 수행된 모바일 기기 진동 관련 연구를 주요 결과 중심으로 요약한 것이다. 모바일 기기에서 발생하는 진동의 물리적 특성, 절대 인지 역치, 인식 강도, 인지적으로 정확한 진동 효과를 유발하기 위한 렌더링 방법 등에 대해서 간략하게 서술한다.

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