• Title/Summary/Keyword: target following

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Apoptotic Cell Death Following Traumatic Injury to the Central Nervous System

  • Springer, Joe E.
    • BMB Reports
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    • v.35 no.1
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    • pp.94-105
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    • 2002
  • Apoptotic cell death is a fundamental and highly regulated biological process in which a cell is instructed to actively participate in its own demise. This process of cellular suicide is activated by developmental and environmental cues and normally plays an essential role in eliminating superfluous, damaged, and senescent cells of many tissue types. In recent years, a number of experimental studies have provided evidence of widespread neuronal and glial apoptosis following injury to the central nervous system (CNS). These studies indicate that injury-induced apoptosis can be detected from hours to days following injury and may contribute to neurological dysfunction. Given these findings, understanding the biochemical signaling events controlling apoptosis is a first step towards developing therapeutic agents that target this cell death process. This review will focus on molecular cell death pathways that are responsible for generating the apoptotic phenotype. It will also summarize what is currently known about the apoptotic signals that are activated in the injured CNS, and what potential strategies might be pursued to reduce this cell death process as a means to promote functional recovery.

A Switched Visual Servoing Technique Robust to Camera Calibration Errors for Reaching the Desired Location Following a Straight Line in 3-D Space (카메라 교정 오차에 강인한 3차원 직선 경로 추종을 위한 전환 비주얼 서보잉 기법)

  • Kim, Do-Hyoung;Chung, Myung-Jin
    • The Journal of Korea Robotics Society
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    • v.1 no.2
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    • pp.125-134
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    • 2006
  • The problem of establishing the servo system to reach the desired location keeping all features in the field of view and following a straight line is considered. In addition, robustness of camera calibration parameters is considered in this paper. The proposed approach is based on switching from position-based visual servoing (PBVS) to image-based visual servoing (IBVS) and allows the camera path to follow a straight line. To achieve the objective, a pose estimation method is required; the camera's target pose is estimated from the obtained images without the knowledge of the object. A switched control law moves the camera equipped to a robot end-effector near the desired location following a straight line in Cartesian space and then positions it to the desired pose with robustness to camera calibration error. Finally simulation results show the feasibility of the proposed visual servoing technique.

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Design of a Gain Scheduling Controller to Improve Pull-in Performance in Optical Disc Drive (광디스크 드라이버의 풀인(pull-in) 성능향상을 위한 이득 스케줄링 제어기의 설계)

  • Kim, Eun-Hee;Oh, Jun-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.5
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    • pp.462-466
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    • 2008
  • This paper proposes a stable gain scheduling method of linear time invariant controllers for tracking servo system. In order to read and write the data on the optical disc, the pick-up head should be moved to the exact track quickly and follow the track immediately. Two different controllers are used for each moving and track-following. In pull-in period, a transition period from moving to track-following, the head might slip and miss the target track. This brings on another searching process and increases the total time. One way to avoid slipping is to extend the bandwidth of the track-following controller. But, extending the bandwidth could degrade the following performance. More prevalent way is to use one more controller in this pull-in period and switch to the following controller. In general, however, switching or scheduling of stable controllers cannot guarantee the stability. This paper suggests an scheduling method guaranteeing the overall stability not only in a generalized form but also in special form for SISO system. The sufficient condition is derived from the fact that Q factor of a stable controller should be stay in $RH_{\infty}$ space. In the experiment, the proposed method shows better performance than the switching method such as shorter time and lower current consumption.

Implementation of Ship Trajectory Following Algorithm

  • Wonjin Choi;Seung-Hwan Jun
    • Journal of Navigation and Port Research
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    • v.47 no.2
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    • pp.49-56
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    • 2023
  • As interest in autonomous ships continues to grow, researchers around the world are dedicating themselves to the development of relevant technologies. However, these technologies are not yet perfect. Several technical problems remain unresolved. To address these problems, this study presents the implementation of a ship trajectory algorithm for group navigation, where followers can navigate by following the trajectory of a leader. The algorithm works by storing the leader's trajectory as a follow-point and by calculating the azimuth using the line-of-sight guidance law to reach it. A course-keeping controller based on PD control is implemented to follow the target course and a speed control algorithm is designed to prevent collisions. Sea experiments were conducted using 1 m class small RC model boats to verify the proposed algorithm. The follower successfully navigated by following the leader's trajectory and maintained the designated distance to the forward boat. This study is significant in that it implements an algorithm for the follower to follow the trajectory of the leader rather than directly following it as in conventional methods, and verifies it through sea experiments.

A research on cyber target importance ranking using PageRank algorithm (PageRank 알고리즘을 활용한 사이버표적 중요성 순위 선정 방안 연구)

  • Kim, Kook-jin;Oh, Seung-hwan;Lee, Dong-hwan;Oh, Haeng-rok;Lee, Jung-sik;Shin, Dong-kyoo
    • Journal of Internet Computing and Services
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    • v.22 no.6
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    • pp.115-127
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    • 2021
  • With the development of science and technology around the world, the realm of cyberspace, following land, sea, air, and space, is also recognized as a battlefield area. Accordingly, it is necessary to design and establish various elements such as definitions, systems, procedures, and plans for not only physical operations in land, sea, air, and space but also cyber operations in cyberspace. In this research, the importance of cyber targets that can be considered when prioritizing the list of cyber targets selected through intermediate target development in the target development and prioritization stage of targeting processing of cyber operations was selected as a factor to be considered. We propose a method to calculate the score for the cyber target and use it as a part of the cyber target prioritization score. Accordingly, in the cyber target prioritization process, the cyber target importance category is set, and the cyber target importance concept and reference item are derived. We propose a TIR (Target Importance Rank) algorithm that synthesizes parameters such as Event Prioritization Framework based on PageRank algorithm for score calculation and synthesis for each derived standard item. And, by constructing the Stuxnet case-based network topology and scenario data, a cyber target importance score is derived with the proposed algorithm, and the cyber target is prioritized to verify the proposed algorithm.

A Study on the Decision-Making of Private Banker's in Recommending Hedge Fund among Financial Goods (은행 금융상품에서 프라이빗 뱅커의 전문투자형 사모펀드 추천 의사결정)

  • Yu, Hwan;Lee, Young-Jai
    • The Journal of Information Systems
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    • v.28 no.4
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    • pp.333-358
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    • 2019
  • Purpose The study aims to develop a data-based decision model for private bankers when recommending hedge funds to their customers in financial institutions. Design/methodology/approach The independent variables are set in two groups. The independent variables of the first group are aggressive investors, active investors, and risk-neutral type investors. In the second group, variables considered by private bankers include customer propensity to invest, reliability, product subscription experience, professionalism, intimacy, and product understanding. A decision-making variable for a private banker is in recommending a first-rate general private fund composed of foreign and domestic FinTech products. These contain dependent variables that include target return rate(%), fund period (months), safeguard existence, underlying asset, and hedge fund name. Findings Based on the research results, there is a 94.4% accuracy in decision-making when the independent variables (customer rating, reliability, intimacy, product subscription experience, professionalism and product understanding) are used according to the following order of relevant dependent variables: step 1 on safeguard existence, step 2 on target return rate, step 3 on fund period, and step 4 on hedge fund name. Next, a 93.7% accuracy is expected when decision-making uses the following order of dependent variables: step 1 on safeguard existence, step 2 on target return rate, step 3 on underlying asset, and step 4 on fund period. In conclusion, a private banker conducts a decision making stage when recommending hedge funds to their customers. When examining a private banker's recommendations of hedge funds to a customer, independent variables influencing dependent variables are intimacy, product comprehension, and product subscription experience according to a categorical regression model and artificial neural network analysis model.

A Basic Study on the Product Development of Dress Forms (의복 생산용 바디 개발을 위한 기초 연구)

  • Cui, Ming-Hai;Jung, Kyong-Won;Nam, Yun-Ja;Choi, Kueng-Mi
    • Fashion & Textile Research Journal
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    • v.8 no.3
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    • pp.317-325
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    • 2006
  • The purposes of this study are to examine clothing businesses which are using dress forms and grasp the problems in apparel manufacturing process, to verify the size and shape of the dress forms for uniformity, to ascertain the uniformity between the dress forms being sold today and the somatotype of the target consumers. The following results were obtained. First, most of the clothing businesses used the existing dress forms in the company. The dress forms didn't reflect the somatotype of the current consumers. And the users satisfaction was below the average. Second, the size and shape of the dress forms being sold today had lack of uniformity between themselves. Third, the dress forms didn't reflect the shape characteristics as well as the size of the target consumers. Consequently, The dress forms need to have the following. First, It is necessary that the dress forms have various functions in a dress form in the future. Second, to get high satisfaction of clothing fit, we need to build up the data base of the consumers somatotype. The data base have to consist of not only circumference but also width, thickness, angle of the current consumers. Last, the further studies of the dress forms need to meet the clothing businesses demand.

Validation of Neurotensin Receptor 1 as a Therapeutic Target for Gastric Cancer

  • Akter, Hafeza;Yoon, Jung Hwan;Yoo, Young Sook;Kang, Min-Jung
    • Molecules and Cells
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    • v.41 no.6
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    • pp.591-602
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    • 2018
  • Gastric cancer is the fifth most common type of malignancy worldwide, and the survival rate of patients with advanced-stage gastric cancer is low, even after receiving chemotherapy. Here, we validated neurotensin receptor 1 (NTSR1) as a potential therapeutic target in gastric cancer. We compared NTSR1 expression levels in sixty different gastric cancer-tissue samples and cells, as well as in other cancer cells (lung, breast, pancreatic, and colon), by assessing NTSR1 expression via semi-quantitative real-time reverse transcription polymerase chain reaction, immunocytochemistry and western blot. Following neurotensin (NT) treatment, we analyzed the expression and activity of matrix metalloproteinase-9 (MMP-9) and further determined the effects on cell migration and invasion via wound-healing and transwell assays. Our results revealed that NTSR1 mRNA levels were higher in gastric cancer tissues than non-cancerous tissues. Both of NTSR1 mRNA levels and expression were higher in gastric cancer cell lines relative to levels observed in other cancer-cell lines. Moreover, NT treatment induced MMP-9 expression and activity in all cancer cell lines, which was significantly decreased following treatment with the NTSR1 antagonist SR48692 or small-interfering RNA targeting NTSR1. Furthermore, NT-mediated metastases was confirmed by observing epithelial-mesenchymal transition markers SNAIL and E-cadherin in gastric cancer cells. NT-mediated invasion and migration of gastric cancer cells were reduced by NTSR1 depletion through the Erk signaling. These findings strongly suggested that NTR1 constitutes a potential therapeutic target for the inhibition of gastric cancer invasion and metastasis.

A Rate Control Algorithm of MPEG-2 Video Encoding Based Target Bit Matching at Scene Changes (장면전환 발생시 예상 비트 조정을 통한 MPEG-2 비디오 부호화 비트율 제어 알고리즘)

  • Moon Ho-seok;Park Sang-sung;Sohn Myung-ho;Jang Dong-sik
    • Journal of KIISE:Software and Applications
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    • v.31 no.12
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    • pp.1621-1627
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    • 2004
  • The decrease of visual quality at scene change occurs when the difference between the amount of target bits and actual coding is high. Especially, scene change at the P-Picture can lead to severely degrade visual qualities at itself and the pictures referencing it. In this paper, under the occurrence of scene change, we propose a new method, based on the analysis of existing inaccurate bits allocation, to improve the visual qualities of scene-changed and following pictures. The method allocates extra bits to scene-changed Picture and changes them upto the level of the complexity of intra picture. Also, the method changes target bits of following pictures upto the complexity of picture prior to the scene change. Computer simulation shows that the proposed method has improved 0.5-1.2dB higher than TM5 method in terms of PSNR.

Cytotoxicity of Anti-CD4 Antibody Activated $CD4^+$ T-Lymphocytes against Herpesvirus-Infected Target Cells is Dependent on $p56^{lck}$ and $p59^{fyn}$ Protein Tyrosine Kinase Activity

  • Choi, Sang-Hoon;Jang, Yong-Suk;Oh, Chan-Ho
    • BMB Reports
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    • v.31 no.4
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    • pp.355-363
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    • 1998
  • MHC unrestricted, antigen nonspecific killing by $CD4^+$ T-cells against virally-infected target cells was induced following cross-linking of CD4 molecules. The cytotoxicity of antibody-activated $CD4^+$ T-cells was abolished by genistein (4',5,7-trihydroxyisoflavone), a protein tyrosine kinase (PTK) inhibitor, but not by H-7, a protein kinase C (PKC) inhibitor. Genisteintreated human or bovine peripheral blood $CD4^+$ T-cells lacked PTK activity and failed to kill virally-infected target cells even after cross-linking of CD4 molecules. The cross-linking of CD4 molecules did not induce effector cell proliferation or the transcription of TNF ${\beta}$. TNF ${\beta}$ synthesis was up-regulated by incubating antibody activated effector cells with bovine herpesvirus type 1 (BHV-1) infected D17 target cells. Anti-TNF ${\beta}$ antibody partially abrogated direct effector cell-mediated antiviral cytotoxicity. On the other hand, this antibody effectively neutralized antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on effector and target cell ratio. These findings have importance to define the mechanisms of how CD4 cytotoxic cells control viral infection.

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