• Title/Summary/Keyword: Self localization

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Current Understanding of the Roles of CD1a-Restricted T Cells in the Immune System

  • Yoo, Hyun Jung;Kim, Na Young;Kim, Ji Hyung
    • Molecules and Cells
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    • v.44 no.5
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    • pp.310-317
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    • 2021
  • Cluster of differentiation 1 (CD1) is a family of cell-surface glycoproteins that present lipid antigens to T cells. Humans have five CD1 isoforms. CD1a is distinguished by the small volume of its antigen-binding groove and its stunted A' pocket, its high and exclusive expression on Langerhans cells, and its localization in the early endosomal and recycling intracellular trafficking compartments. Its ligands originate from self or foreign sources. There are three modes by which the T-cell receptors of CD1a-restricted T cells interact with the CD1a:lipid complex: they bind to both the CD1a surface and the antigen or to only CD1a itself, which activates the T cell, or they are unable to bind because of bulky motifs protruding from the antigen-binding groove, which might inhibit autoreactive T-cell activation. Recently, several studies have shown that by producing TH2 or TH17 cytokines, CD1a-restricted T cells contribute to inflammatory skin disorders, including atopic dermatitis, psoriasis, allergic contact dermatitis, and wasp/bee venom allergy. They may also participate in other diseases, including pulmonary disorders and cancer, because CD1a-expressing dendritic cells are also located in non-skin tissues. In this mini-review, we discuss the current knowledge regarding the biology of CD1a-reactive T cells and their potential roles in disease.

Time Synchronization Technique for GNSS Jamming Monitoring Network System (GNSS 재밍 신호 모니터링 네트워크 시스템을 위한 독립된 GNSS 수신기 간 시각 동기화 기법)

  • Jin, Gwon gyu;Song, Young jin;Won, Jong hoon
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.20 no.3
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    • pp.74-85
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    • 2021
  • Global Navigation Satellite System (GNSS) receivers are intrinsically vulnerable to radio frequency jamming signals due to the fundamental property of radio navigation systems. A GNSS jamming monitoring system that is capable of jamming detection, classification and localization is essential for infrastructure for autonomous driving systems. For these 3 functionalities, a GNSS jamming monitoring network consisting of a multiple of low-cost GNSS receivers distributed in a certain area is needed, and the precise time synchronizaion between multiple independent GNSS receivers in the network is an essential element. This paper presents a precise time synchronization method based on the direct use of Time Difference of Arrival (TDOA) technique in signal domain. A block interpolation method is additionally incorporated into the method in order to maintain the precision of time synchronization even with the relatively low sampling rate of the received signals for computational efficiency. The feasibility of the proposed approach is verified in the numerical simualtions.

Development of Variable Vacuum Capacitor with Maximum Voltage of 12 kV and Capacitance of 50 to 500 pF (최대 전압 12 kV, 커패시턴스 50~500 pF 가변 진공커패시터 개발)

  • Cha, Youngkwang;Lee, Ilhoi;Jeon, Kibeom;Jang, Jihoon;Ju, Heungjin;Choi, aSeungkil
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.35 no.3
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    • pp.232-240
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    • 2022
  • A variable vacuum capacitor (VVC), which is a variable element, is used to match impedance in plasma that changes with various impedance values, and its use is expanding with the rapid growth of the semiconductor business. Since VVCs have to secure insulation performance and vary capacitance within a compact size, electrode design and manufacturing are very important; thus, various technologies such as part design and manufacturing technology and vacuum brazing technology are required. In this study, based on the model of an advanced foreign company that is widely used for impedance matching in the manufacture of semiconductors and displays, a VVC that can realize the same performance was developed. The electrode part was designed, the consistency was confirmed through analysis, and the precision of capacitance was improved by designing a cup-type electrode to secure the concentricity of the electrode. As a result of the evaluation, all requirements was satisfied. We believe that self-development will be possible if satisfactory responses are received through evaluation by VVC consumers in the future.

Research for robot kidnap problem in the indoor of utilizing external image information and the absolute spatial coordinates (실내 공간에서 이동 로봇의 납치 문제 해결을 위한 외부 영상 정보 및 절대 공간 좌표 활용 연구)

  • Jeon, Young-Pil;Park, Jong-Ho;Lim, Shin-Teak;Chong, Kil-To
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.3
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    • pp.2123-2130
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    • 2015
  • For such automatic monitoring robot or a robot cleaner that is utilized indoors, if it deviates from someone by replacement or, or of a mobile robot such as collisions with unexpected object direction or planned path, based on the planned path There is a need to come back to, it is necessary to tough self-position estimation ability of mobile robot in this, which is also associated with resolution of the kidnap problem of conventional mobile robot. In this study, the case of a mobile robot, operates indoors, you want to take advantage of the low cost of the robot. Therefore, in this paper, by using the acquisition device to an external image information such as the CCTV which is installed in a room, it acquires the environment image and take advantage of marker recognition of the mobile robot at the same time and converted it absolutely spatial coordinates it is, we are trying to solve the self-position estimation of the mobile robot in the room and kidnap problem and actual implementation methods potential field to try utilizing robotic systems. Thus, by implementing the method proposed in this study to the actual robot system, and is promoting the relevant experiment was to verify the results.

Study of Robust Position Recognition System of a Mobile Robot Using Multiple Cameras and Absolute Space Coordinates (다중 카메라와 절대 공간 좌표를 활용한 이동 로봇의 강인한 실내 위치 인식 시스템 연구)

  • Mo, Se Hyun;Jeon, Young Pil;Park, Jong Ho;Chong, Kil To
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.7
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    • pp.655-663
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    • 2017
  • With the development of ICT technology, the indoor utilization of robots is increasing. Research on transportation, cleaning, guidance robots, etc., that can be used now or increase the scope of future use will be advanced. To facilitate the use of mobile robots in indoor spaces, the problem of self-location recognition is an important research area to be addressed. If an unexpected collision occurs during the motion of a mobile robot, the position of the mobile robot deviates from the initially planned navigation path. In this case, the mobile robot needs a robust controller that enables the mobile robot to accurately navigate toward the goal. This research tries to address the issues related to self-location of the mobile robot. A robust position recognition system was implemented; the system estimates the position of the mobile robot using a combination of encoder information of the mobile robot and the absolute space coordinate transformation information obtained from external video sources such as a large number of CCTVs installed in the room. Furthermore, vector field histogram method of the pass traveling algorithm of the mobile robot system was applied, and the results of the research were confirmed after conducting experiments.

Improvement of Face Recognition Algorithm for Residential Area Surveillance System Based on Graph Convolution Network (그래프 컨벌루션 네트워크 기반 주거지역 감시시스템의 얼굴인식 알고리즘 개선)

  • Tan Heyi;Byung-Won Min
    • Journal of Internet of Things and Convergence
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    • v.10 no.2
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    • pp.1-15
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    • 2024
  • The construction of smart communities is a new method and important measure to ensure the security of residential areas. In order to solve the problem of low accuracy in face recognition caused by distorting facial features due to monitoring camera angles and other external factors, this paper proposes the following optimization strategies in designing a face recognition network: firstly, a global graph convolution module is designed to encode facial features as graph nodes, and a multi-scale feature enhancement residual module is designed to extract facial keypoint features in conjunction with the global graph convolution module. Secondly, after obtaining facial keypoints, they are constructed as a directed graph structure, and graph attention mechanisms are used to enhance the representation power of graph features. Finally, tensor computations are performed on the graph features of two faces, and the aggregated features are extracted and discriminated by a fully connected layer to determine whether the individuals' identities are the same. Through various experimental tests, the network designed in this paper achieves an AUC index of 85.65% for facial keypoint localization on the 300W public dataset and 88.92% on a self-built dataset. In terms of face recognition accuracy, the proposed network achieves an accuracy of 83.41% on the IBUG public dataset and 96.74% on a self-built dataset. Experimental results demonstrate that the network designed in this paper exhibits high detection and recognition accuracy for faces in surveillance videos.

Development and Application of an Informal Elementary Science Education Program Emphasizing 'Participation and Action' ('참여와 실천' 차원을 강조한 비형식 초등 과학교육 프로그램의 개발 및 적용)

  • Kim, Hyunguk;Shin, Chaeyeon;Park, Jiwon;Song, Jinwoong
    • Journal of Korean Elementary Science Education
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    • v.43 no.2
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    • pp.337-352
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    • 2024
  • This study develops an informal science education program based on a creative design for the promotion of participation and action and explores the validity and effectiveness of the program. The program consists of three mini-projects, namely, The Martian: Surviving from the Mars, So Good to Have Seonjeongneung, and Designing a Sunshine Restaurant, with distinct topics focusing on the localization and contextualization of the region in which the program was implemented to encourage students' participation and action. The researchers selected three topics for each mini-project through discussions and revisions. The program is designed for 42 lessons across the three mini-projects and offers a presentation session in which students present their learnings from the program, constructed to facilitate personal contextualization. Participants included 15 elementary school students from Grades 5 and 6 who took surveys before and after the program. The pre-post surveys comprised two dimensions, 'Participation and Action' and 'Positive Experience about Science,' to examine the effectiveness of the program. At the end of the survey, we added a self-descriptive question that allows students to freely write down their feelings and thoughts. We checked the students' thoughts. The effectiveness of the program was illustrated by the largest increase in the "safe society" category, whereas there was little increase in other categories under the 'participation and Action' dimension in the Korean Science Education Standards. 'Science-related Self-concept' exhibited the largest increase, whereas the other categories displayed little increase from the 'Positive Experience about Science' dimension category.

A Study on the Development of a Home Mess-Cleanup Robot Using an RFID Tag-Floor (RFID 환경을 이용한 홈 메스클린업 로봇 개발에 관한 연구)

  • Kim, Seung-Woo;Kim, Sang-Dae;Kim, Byung-Ho;Kim, Hong-Rae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.2
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    • pp.508-516
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    • 2010
  • An autonomous and automatic home mess-cleanup robot is newly developed in this paper. Thus far, vacuum-cleaners have lightened the burden of household chores but the operational labor that vacuum-cleaners entail has been very severe. Recently, a cleaning robot was commercialized to solve but it also was not successful because it still had the problem of mess-cleanup, which pertained to the clean-up of large trash and the arrangement of newspapers, clothes, etc. Hence, we develop a new home mess-cleanup robot (McBot) to completely overcome this problem. The robot needs the capability for agile navigation and a novel manipulation system for mess-cleanup. The autonomous navigational system has to be controlled for the full scanning of the living room and for the precise tracking of the desired path. It must be also be able to recognize the absolute position and orientation of itself and to distinguish the messed object that is to be cleaned up from obstacles that should merely be avoided. The manipulator, which is not needed in a vacuum-cleaning robot, has the functions of distinguishing the large trash that is to be cleaned from the messed objects that are to be arranged. It needs to use its discretion with regard to the form of the messed objects and to properly carry these objects to the destination. In particular, in this paper, we describe our approach for achieving accurate localization using RFID for home mess-cleanup robots. Finally, the effectiveness of the developed McBot is confirmed through live tests of the mess-cleanup task.

A Study on the Clinical Usefulness of MMSE and BCRS for Cognitive Function Test in Patients with Non-Traumatic Subcortical Cerebrovascular Disease (비외상성 피질하 뇌혈관질환 환자에서 인지평가도구로서 정신상태소검사(MMSE)와 간이인지평가척도(BCRS)의 임상적 유용성에 대한 연구)

  • Choi, Hong;Lee, Young-Ho;Choi, Young-Hee;Ko, Dae-Kwan;Chung, Young-Cho;Park, Byoung-Kwan;Kim, Soo-Ji;Chung, Sook-Haui;Ko, Byoung-Hee;Song, Il-Byoung;Park, Kun-Woo;Lee, Dae-Hie
    • Sleep Medicine and Psychophysiology
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    • v.3 no.1
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    • pp.68-78
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    • 1996
  • Objective : The Mini-Mental State Examination(MMSE) and Brief Cognitive Rating Scale(BCRS) are frequently using screening tests fur evaluating the cognitive function in clinical practice and research. The authors tried to evaluate the clinical usefulness of these tests for the patients with non-traumatic subcortical cerebrovascular disease. Method : We administered the MMSE and BCRS to 85 patients and 195 normal control group. In order to compare the test results according to the lesion site, we divided patients into left sided lesion group(21 patients), right sided lesion group(31 patients) and both sided lesion group(13 patients). Their cognitive function was evaluated by the BNA and daily living functional activity was examined by the IADLs(Instrumental Activities of Daily Living Scale)and GERRI(Geriatric Evaluation by Relative's Rating Instrument). Results : The results are as follows : 1) In the BNA, the patients scored significantly lower than control group at all items(except Right-Left Orientation and Motor Impersistence), but there were no difference in the MMSE(total score and all 5 items), and only 2 items(recent memory and self-care) were significantly different between two groups in the BCRS. 2) In the comparison by lateralization, there were significant differences among three groups at 3 items(Left Tactile Form Perception, Left Finger Localization and Right Finger Localization) in the BNA. But, there were no difference in the MMSE and BCRS. 3) In the correlation between daily living functioning and the MMSE/BCRS, control group showed no relation(except item of cognitive functioning), but patient group was significantly correlated with 3 items(social functioning, instrumental activities of daily living and cognitive functioning). Conclusions : These findings suggest that MMSE and BCRS are not useful as the test for cognitive function and discrimination of lateralization in patients with non-traumatic subcortical cerebrovascular disease. However, scores of these tests may be related with the functional level(such as daily living function) of patients.

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Difference of Pain Description According to Gender in the Elderly (노인의 성별 만성동통 호소의 차이에 대한 조사연구)

  • 김명애;박경민;김효정
    • Journal of Korean Academy of Nursing
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    • v.28 no.2
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    • pp.369-379
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    • 1998
  • Despite acknowledgment that pain is likely to be a major problem for many older adults, it is difficult to estimate the frequency of pain problems for this population. The main purpose of this study was to identify the various characteristics of chronic pain in the elderly by gender. It examines by gender, pain frequency, pain intensity, number of chronic pain sites, localization of pain, impact on activities, methods of pain management, and effects of chronic pain management. The subjects were 189 elderly people(65 years and older) living in an urban area. They were surveyed at their homes. They were surveyed by interview using a closed-ended questionnaire. The survey was done from Nov. 6th. to Dec. 6th. 1997. Descriptive statistics were used to determine all of the reported pain variables. Chi-square tests were used to determine crude differences between pain intensity and gender. T-test was used to determine differences in number of pain sites between men and women. The findings are as follows ; Of the 189 subjects, 83.6% reported experiencing pain, and men reported a lower prevalence (69.5%) than women(89.2%). Women had significantly more severe pain than did men(p=.001). Lower back pain(20.2%) and leg pain(20.2%) were the most prevalent, followed by knee pain(17.4%), arm pain(13.3%), neck and shoulder pain(11.6%), and headache(9.9%). Women experienced more multiple localizations of pain(p=.0001), the greatest impact was on movement (83.5%) , followed by usual activities(60.8%), sleep(49.4%), visiting(29.1%), and hobbies and recreations(50.0%). No differences were observed between men and women in the proportion of subjects reporting a negative impact on each of these activities. The methods of pain management were hospital visit(70.9%), drug store medication(46.7%), oriental medicine clinic(32.9%), endurance(13.3%), self-management(6.3%). Drug therapy was the most effective pain management strategy(94%), followed by physical therapy(63%) and accupuncture.byssocausis(55%). The conclusion : Pain is a symptom of great clinical importance that is often associated with disability, loss of independence, and reduced quality of life. In this study chronic pain symptoms were common but unevenly distributed in men and women. The results further advance understanding of the experience and impact of pain by gender. Future studies should incorporate questions that gather systemic and more detailed information on the characteristics of pain, especially by gender and by age.

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