• Title/Summary/Keyword: critical target

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Passive Ranging Based on Planar Homography in a Monocular Vision System

  • Wu, Xin-mei;Guan, Fang-li;Xu, Ai-jun
    • Journal of Information Processing Systems
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    • v.16 no.1
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    • pp.155-170
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    • 2020
  • Passive ranging is a critical part of machine vision measurement. Most of passive ranging methods based on machine vision use binocular technology which need strict hardware conditions and lack of universality. To measure the distance of an object placed on horizontal plane, we present a passive ranging method based on monocular vision system by smartphone. Experimental results show that given the same abscissas, the ordinatesis of the image points linearly related to their actual imaging angles. According to this principle, we first establish a depth extraction model by assuming a linear function and substituting the actual imaging angles and ordinates of the special conjugate points into the linear function. The vertical distance of the target object to the optical axis is then calculated according to imaging principle of camera, and the passive ranging can be derived by depth and vertical distance to the optical axis of target object. Experimental results show that ranging by this method has a higher accuracy compare with others based on binocular vision system. The mean relative error of the depth measurement is 0.937% when the distance is within 3 m. When it is 3-10 m, the mean relative error is 1.71%. Compared with other methods based on monocular vision system, the method does not need to calibrate before ranging and avoids the error caused by data fitting.

3-D High Resolution Ultrasonic Transmission Tomography and Soft Tissue Differentiation

  • Kim Tae-Seong
    • Journal of Biomedical Engineering Research
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    • v.26 no.1
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    • pp.55-63
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    • 2005
  • A novel imaging system for High-resolution Ultrasonic Transmission Tomography (HUTT) and soft tissue differentiation methodology for the HUTT system are presented. The critical innovation of the HUTT system includes the use of sub-millimeter transducer elements for both transmitter and receiver arrays and multi-band analysis of the first-arrival pulse. The first-arrival pulse is detected and extracted from the received signal (i.e., snippet) at each azimuthal and angular location of a mechanical tomographic scanner in transmission mode. Each extracted snippet is processed to yield a multi-spectral vector of attenuation values at multiple frequency bands. These vectors form a 3-D sinogram representing a multi-spectral augmentation of the conventional 2-D sinogram. A filtered backprojection algorithm is used to reconstruct a stack of multi-spectral images for each 2-D tomographic slice that allow tissue characterization. A novel methodology for soft tissue differentiation using spectral target detection is presented. The representative 2-D and 3-D HUTT images formed at various frequency bands demonstrate the high-resolution capability of the system. It is shown that spherical objects with diameter down to 0.3㎜ can be detected. In addition, the results of soft tissue differentiation and characterization demonstrate the feasibility of quantitative soft tissue analysis for possible detection of lesions or cancerous tissue.

Redox Regulation of Apoptosis before and after Cytochrome C Release

  • Chen, Quan;Crosby, Meredith;Almasan, Alex
    • Animal cells and systems
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    • v.7 no.1
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    • pp.1-9
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    • 2003
  • Programmed cell death, or apoptosis, is one of the most studied areas of modern biology. Apoptosis is a genetically regulated process, which plays an essential role in the development and homeostasis of higher organisms. Mitochondria, known to play a central role in regulating cellular metabolism, was found to be critical for regulating apoptosis induced under both physiological and pathological conditions. Mitochondria are a major source of reactive oxygen species (ROS) but they can also serve as its target during the apoptosis process. Release of apoptogenic factors from mitochondria, the best known of which is cytochrome c, leads to assembly of a large apoptosis-inducing complex called the apoptosome. Cysteine pretenses (called caspases) are recruited to this complex and, following their activation by proteolytic cleavage, activate other caspases, which in turn target for specific cleavage a large number of cellular proteins. The redox regulation of apoptosis during and after cytochrome c release is an area of intense investigation. This review summarizes what is known about the biological role of ROS and its targets in apoptosis with an emphasis on its intricate connections to mitochondria and the basic components of cell death.

A Critical Review on the Government-driven Language Culture Improvement Projects: Focusing on the Pan-national Language Culture Improvement Movement 'Annyeong! Urimal(Hello! Our Language)' (정부 주도 언어문화개선 사업에 대한 비판적 고찰 -범국민 언어문화개선 운동 '안녕! 우리말'을 중심으로-)

  • CHO, TAE-RIN
    • Korean Linguistics
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    • v.79
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    • pp.145-169
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    • 2018
  • The purpose of this paper is to review critically the validity and relevance of the pan-national language culture improvement movement, Annyeong! Urimal(Hello! Our Language) implemented for the last three years as part of the government-driven projects, and to seek for improvement direction or fundamental reorientation of this movement. In order to accomplish this purpose, this paper firstly points out abstract and conventional aspects of the diagnosis for background and the purpose of projects, and suggests that this movement focuses on verbal abuse rather than language destruction and pays attention to positive aspects of newly rising language use. Then, with reference to main agent, this paper argues that the government must lead actively formation of voluntary nongovernmental agent with indirect financial and institutional support. Thirdly, it is suggested that public language should be the top priority target sphere and the language used by the leaders of society and the older generation should be also included in the target spheres of this movement. Finally, this paper indicates that enlightenment/public relation projects end often in one time events, imposing unilaterally the normative contents, and also emphasizes the importance of survey/research projects and deliberation/evaluation projects.

Critical Factors Affecting Student Satisfaction and Loyalty: An Empirical Study in Cambodia

  • KIENG, Rotana;PHOTHIKITTI, Kitti;VONGURAI, Rawin
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.7
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    • pp.225-234
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    • 2021
  • This research aimed to investigate the key factors affecting student satisfaction and loyalty in selected private universities in Cambodia. The study implemented a quantitative survey designed and guided by seven hypotheses to test the causal relationships among variables, such as academic experience, faculty services, campus life, social integration, student support facilities, student satisfaction, university image, and student loyalty. The research applied a multi-stage sampling technique of probability procedures to guarantee the presence of the research population. Confirmatory Factor Analysis (CFA) and Structural Equation Modeling (SEM) were applied for data analysis to test the hypotheses model. The collected survey totaled 543 from three universities. The purposive sampling methods were used to select the three target universities, based on their reputation, the number of students, year of establishment, and the recognition from the Ministry of Education, Youth, and Sport. The stratified random sampling method was employed to select target respondents for data collection by dividing the population into subgroups to ensure a random sample. The results showed that student support facilities, campus life, and social integration, faculty services, and university image play very important roles in the satisfaction and loyalty of the students in three universities.

Multimodal Attention-Based Fusion Model for Context-Aware Emotion Recognition

  • Vo, Minh-Cong;Lee, Guee-Sang
    • International Journal of Contents
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    • v.18 no.3
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    • pp.11-20
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    • 2022
  • Human Emotion Recognition is an exciting topic that has been attracting many researchers for a lengthy time. In recent years, there has been an increasing interest in exploiting contextual information on emotion recognition. Some previous explorations in psychology show that emotional perception is impacted by facial expressions, as well as contextual information from the scene, such as human activities, interactions, and body poses. Those explorations initialize a trend in computer vision in exploring the critical role of contexts, by considering them as modalities to infer predicted emotion along with facial expressions. However, the contextual information has not been fully exploited. The scene emotion created by the surrounding environment, can shape how people perceive emotion. Besides, additive fusion in multimodal training fashion is not practical, because the contributions of each modality are not equal to the final prediction. The purpose of this paper was to contribute to this growing area of research, by exploring the effectiveness of the emotional scene gist in the input image, to infer the emotional state of the primary target. The emotional scene gist includes emotion, emotional feelings, and actions or events that directly trigger emotional reactions in the input image. We also present an attention-based fusion network, to combine multimodal features based on their impacts on the target emotional state. We demonstrate the effectiveness of the method, through a significant improvement on the EMOTIC dataset.

A Freeze-drying Formulation and Target Specificity of Double-stranded RNA-expressing Bacteria to Control Insect Pests (Double-stranded RNA 발현 세균의 동결건조 제형화와 적용 대상 해충 선택성)

  • Kim, Eunseong;Kim, Yonggyun
    • Korean journal of applied entomology
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    • v.55 no.2
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    • pp.81-89
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    • 2016
  • Double-stranded RNA (dsRNA) has been applied to control insect pests by its suppressive activity against specific target genes. Integrin is a heterodimer (${\alpha}$ and ${\beta}$) transmembrane protein and plays a critical role in cell-to-cell or cell-to-extracellular matrix interactions in eukaryotes. Suppression of ${\beta}$ subunit integrin gene expression by its specific dsRNA (= dsINT) induces significant mortality against target insects. Furthermore, a recombinant bacterium expressing dsINT is potent to kill target insects. However, it is necessary to develop a formulation technique of the dsRNA-expressing bacteria to apply the bacterial insecticide against field populations. This study formulated the recombinant bacteria by freeze-drying and tested its control efficacy against target insects. The formulation maintained significant insecticidal activity against last instar larvae of Spodoptera exigua. While a commercial Bacillus thuringiensis (Bt) insecticide exhibited only about 60% insecticidal activity against S. exigua last instar, an addition of the dsINT-expressing bacterial formulation significantly enhanced the Bt insecticidal activity. The dsINT-expressing bacterial formulation exhibited relative selectivity to target insects depending on sequence similarity. These results indicate that a freeze-dried form of dsRNA-expressing bacteria keeps its insecticidal activity.

Airborne Video as a Remote Sensor for Linear Target : Academic Research and Field Practices (선형지상물체에 대한 원격센서로서의 항공비디오 : 연구추세 및 실무에서 사용현황)

  • 엄정섭
    • Korean Journal of Remote Sensing
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    • v.15 no.2
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    • pp.159-174
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    • 1999
  • An important aspect of remote sensing research would be ultimately the production of research output so that operational people can directly use it. However, for the strip target, it is not certain how the research output in remote sensing helps the field user in adopting and utilizing the technology successfully. The relative limitation of traditional remote sensing systems for such a linear application is briefly discussed and the strength of videography are highlighted. Based on the postulated advantages of video as corridor sensor, a careful and extensive investigation has been made of research trends for airborne videography to identify how past research matches to demand of field clients. It is found that while video has been operationally used for strip target in field client communities, much research effort has been directed to area target, and relatively little towards the classification and monitoring of linear target. From this critical review, a very important step has been made concerning the practicality of airborne videography. The value of this paper is warranted in proposing a new concept of video strip monitoring(VSM) as future research direction in recognition of sensor characteristics and limitations. Ultimately, the suggestion in this paper will greatly contribute to opening new possibilities for implementing VSM, proposed as an initial aim of this paper.

Study on the Flutter Prediction of the Miniature Guided-bullet Control Surface System (초소형 유도탄 구동날개 시스템의 플러터 예측에 관한 연구)

  • Lee, Seongheon;Cho, Youngki;Cho, Hanjin;Bang, Hyochoong
    • Journal of the Korea Institute of Military Science and Technology
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    • v.20 no.1
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    • pp.148-157
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    • 2017
  • Miniature guided-bullet is an advanced military technology of developing guided missile which is designed to hit a target precisely while having easily carriable miniature size. A key issue of developing such system involves size reduction of the original guided missile system, and this in turn arouses stiffness issue regarding small and thin sized control surface. In this study, procedures on how to calculate the critical flutter speed of special type of control surface with the change of its dimension or material property is arranged. During this procedure, design parameters related to critical flutter speed are abridged to help preliminary design of similar structure even faster than time-consuming, and cumbersome computer analysis.

Hitting Probability on the Moving Target (이동표적에 대한 적중확률)

  • Oh H.J.
    • Journal of the military operations research society of Korea
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    • v.1 no.1
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    • pp.111-129
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    • 1975
  • U.S. Air Force Regulation 80-1 defines that a weapon system is composed of equipments, skills, and techniques, the composite of which ferns an instrument of combat. The complete weapon system includes all related facilities, equipments, materials, services, and personnels required for the operation of the system, so that the instrument of combat can be considered as a self-sufficient unit of striking power in its intended operational environment. Effectiveness of a weapon system can be expressed as a function of its liability, reliability and performance capability. Among these attributes which influence the weapon effectiveness, performance capability is considered to be the most critical factor for many weapon systems. In order to illustrate the application of the methodology of performance capability, a specific ease study on the effectiveness of Vulcan anti-air craft gun system is presented with special emphasis on hitting probability on moving targets, effects of artificial rounds dispersion, and several principles related to the deployment of the system. This thesis includes the thorough survey of the possibility of calculating the absolute value of hitting probability on moving targets, indicates that the effects of artificial rounds dispersion increase the value of probability only when the total number of rounds fired within fire range exceeds a certain critical number, and suggests that concentrated guns deployment is better than scattered deployment in order to obtain higher probability and lower average amount of rounds if it is assumed that the effects of counter-attack from enemy threats are not serious.

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