• Title/Summary/Keyword: real-time mechanism

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Feasibility Study of Robotics-based Patient Immobilization Device for Real-time Motion Compensation

  • Chung, Hyekyun;Cho, Seungryong;Cho, Byungchul
    • Progress in Medical Physics
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    • v.27 no.3
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    • pp.117-124
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    • 2016
  • Intrafractional motion of patients, such as respiratory motion during radiation treatment, is an important issue in image-guided radiotherapy. The accuracy of the radiation treatment decreases as the motion range increases. We developed a control system for a robotic patient immobilization system that enables to reduce the range of tumor motion by compensating the tumor motion. Fusion technology, combining robotics and mechatronics, was developed and applied in this study. First, a small-sized prototype was established for use with an industrial miniature robot. The patient immobilization system consisted of an optical tracking system, a robotic couch, a robot controller, and a control program for managing the system components. A multi speed and position control mechanism with three degrees of freedom was designed. The parameters for operating the control system, such as the coordinate transformation parameters and calibration parameters, were measured and evaluated for a prototype device. After developing the control system using the prototype device, a feasibility test on a full-scale patient immobilization system was performed, using a large industrial robot and couch. The performances of both the prototype device and the realistic device were evaluated using a respiratory motion phantom, for several patterns of respiratory motion. For all patterns of motion, the root mean squared error of the corresponding detected motion trajectories were reduced by more than 40%. The proposed system improves the accuracy of the radiation dose delivered to the target and reduces the unwanted irradiation of normal tissue.

Dynamic slot allocation scheme for rt-VBR services in the wireless ATM networks (무선 ATM망에서 rt-VBR 서비스를 위한 동적 슬롯 할당 기법)

  • Yang, Seong-Ryoung;Lim, In-Taek;Heo, Jeong-Seok
    • The KIPS Transactions:PartC
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    • v.9C no.4
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    • pp.543-550
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    • 2002
  • This paper proposes the dynamic slot allocation method for real-time VBR (rt-VBR) services in wireless ATM networks. The proposed method is characterized by a contention-based mechanism of the reservation request, a contention-free polling scheme for transferring the dynamic parameters. The base station scheduler allocates a dynamic parameter minislot to the wireless terminal for transferring the residual lifetime and the number of requesting slots as the dynamic parameters. The scheduling algorithm uses a priority scheme based on the maximum cell transfer delay parameter. Based on the received dynamic parameters, the scheduler allocates the uplink slots to the wireless terminal with the most stringent delay requirement. The simulation results show that the proposed method guarantee the delay constraint of rt-VBR services along with its cell loss rate significantly reduced.

The QoS Adaptive AQM Algorithm and Performance Evaluation for Multimedia Service (멀티미디어 서비스를 위한 QoS 적응형 AQM 알고리즘 및 성능분석)

  • Kang, Hyun-Myoung;Rhee, Woo-Seop
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.6B
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    • pp.605-614
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    • 2009
  • Existing Internet services were almost supported by the best effort service such as the data transmission service and were allowed the transmission delay and packet loss. However, recent Internet multimedia services such as Internet phone, Internet broadcasting are required a real-time processing and high bandwidth. Therefore, many studies for providing Internet QoS are performed at IETF (Internet Engineering Task Force). As the buffer management mechanism among IP QoS methods, active queue management method such as RED (Random Early Detection) algorithm has proposed. However, RED algorithm has a limitation of usage of an average buffer length and unfairness. So, many algorithms proposed as the modified algorithm of RED. But these modified algorithms also have difficulties to satisfy the requirements of various Internet user QoS. Therefore, in this paper we propose the QoS adaptive AQM (Active Queue Management) algorithm for the multimedia services that request various QoS requirements and present a performance evaluation by the simulations using the ns-2.

Dual Token Bucket based HCCA Scheduler for IEEE 802.11e (IEEE 802.11e WLAN 위한 이중 리키 버킷 기반 HCCA 스케줄러)

  • Lee, Dong-Yul;Lee, Chae-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.11B
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    • pp.1178-1190
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    • 2009
  • IEEE 802.11e proposed by IEEE 802.11 working group to guarantee QoS has contention based EDCA and contention free based HCCA. HCCA, a centralized polling based mechanism of 802.11e, needs a scheduling algorithm to allocate the network resource efficiently. The existing standard scheduler, however, is inefficient to support for QoS guarantee for real-time service having VBR traffic. To efficiently assign resource for VBR traffic, in this paper, we propose TXOP algorithm based on dual leaky bucket using average resource allocation and peak resource allocation. The minimum TXOP of each station is obtained by using statistical approach to maximize number of stations of which performance satisfy QoS target. Simulation results show that the proposed algorithm has much higher performance compared with reference scheduler in terms of throughput and delay.

Suppressive Effect of SaengRyoSaMulTang on Activated RBL-2H3 Mast Cells (RBL-2H3 비만세포의 알레르기 염증 반응에 미치는 생료사물탕(生料四物湯)의 영향)

  • Son, Mi-Ju;Han, Jae-Kyung;Kim, Yun-Hee
    • The Journal of Pediatrics of Korean Medicine
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    • v.25 no.1
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    • pp.28-39
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    • 2011
  • Objectives: SaengRyoSaMulTang is a herbal formula in Oriental Medicine, known anti-allergens. However, its mechanism and cellular targets have not been found yet. Thus the study has developed to investigate the suppressive effect of SaengRyoSaMulTang. Methods: In the study, cellular viability, IL-4, IL-13 mRNA expression, IL-4, IL-13 production, manifestations of GATA-1, GATA-2, NF-AT1, NF-AT2, AP-1 and NF-${\kappa}$B p65 transcription factors were examined by Real-Time PCR, ELISA analysis and western blotting. Results: As a result of treating with SaengRyoSaMulTang extract(SRSMT), the study has shown that the amount of Th2 cytokines, which include PI induced IL-4 and IL-13, plays a significant role in suppressing effect. RBL-2H3 mast cells significantly suppressed the PI-induced Th2 cytokine production including IL-4 and IL-13 in a dose dependent manner. PI-induced IL-4 and IL-13 production was significantly suppressed by SRSMT intervention. Western blot analysis of transcription factors involving IL-4 and IL-13 expression also revealed a prominent decreases of mast cell's specific transcription factors including GATA-1, GATA-2, NF-AT2, c-Jun and c-Fos, but NF-${\kappa}$B p65. Conclusions: The study suggests that the anti-allergenic activities of SRSMT may regulate the transcription factors GATA-1, GATA-2, NF-AT2, c-Jun and c-Fos inhibiting Th2 cytokines IL-4 and IL-13 in mast cells.

Comparative Analysis of Biomechanic Variables between Backlift and Leglift Type (BACKLIFT와 LEGLIFT의 들기 유형에 따른 역학적 변인 비교분석)

  • Kim, Eui-Hwan;Kim, Tae-Whan;Kim, Sung-Sup;Chung, Chea-Wook
    • Korean Journal of Applied Biomechanics
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    • v.17 no.4
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    • pp.209-219
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    • 2007
  • The purpose of this study was to analyze biomechanical mechanism (posture, moment of back joint, EMG) when athletes (Judo, Ssirum) and lay people lifted a load according to two different lift methods; backlift and leglift. The number of subjects was 12; 8 athletes (4 for Judo, 4 for Ssirum) and 4 lay people. We recorded a lift motion in backlift and leglift using 7 real time infrared cameras (vicon) and analyzed EMG pattern of major muscles for a lift (lattisimus dorsi, erector spinae, biceps femoris). In a backlift Judo players showed a biggest range of back flexion and extension motion and lay people flexed more than other groups at phase 2 in which an interaction between groups and events was statistically significant (p=.024). In a leglift Ssirum players more flexed their back in a barbell lift and there was a statistical significance (p=.021) between groups and events. For moment of back joints, 1) in a backlift a larger loading on back joints in all three groups at phase 2 when lifting down a barbell, 2) in a leglift a larger loading on back joints when lifting down a barbell in two athlete groups but a larger loading when lifting up a barbell in lay people group, and all groups did not show any statistical significance. For EMG, right lattisimus dorsi muscle in a backlift was statistical significant (p=.006) in an interaction between groups and phase but left lattisimus dorsi muscle was insignicant, and there was not any significance in a leglift. Generally atheletes (Judo and Ssirum) used more their muscles of lower extremity in lifting up and down and lay people did more their ones of upper extremity.

Expressional Profiling of Molecules Associated with Epigenetic Methylation-Related Fertility in the Rat Testis during Postnatal Period

  • Seo, Hee-Jung;Lee, Seong-Kyu;Baik, Haing-Woon;Lee, Ki-Ho
    • Journal of Animal Science and Technology
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    • v.54 no.3
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    • pp.157-163
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    • 2012
  • The male reproduction is precisely controlled by a number of intrinsic and extrinsic factors. These factors usually involve in expressional regulation of various molecules influencing on sperm production in the testis. A number of ways are employed to control the transcription of specific genes, including epigenetic modifications of DNA and histone molecules. DNA methylation of CpG dinucleotides is a commonly used regulatory mechanism for testicular genes associated with the fertility. Previous studies have demonstrated the infertility induced by improper DNA methylation of these genes. In the present research, we attempted to determine transcriptional expression of some of these genes in the rat testis at different postnatal ages using real-time PCR analysis. These genes include neurotrophin 3 (Ntf3), insulin-like growth factor II (Igf2), JmjC-domain-containing histone demethylase 2A 1 (Jhm2da), paired box 8 transcription factor (Pax8), small nuclear ribonucleoprotein polypeptide N (Snrpn), and 5,10-methylenetetrahydrofolate reductase (Mthfr). The expression levels of Ntf3, Igf2, and Snrpn genes were the highest at the neonatal age, followed by transient decreases at the prepubertal age. Expression of Jhm2da and Mthfr genes were continuously increased from the neonate to 1 year of age. The levels of Pax8 mRNA at the early ages were higher than those at the later ages of postnatal development. These findings suggest that expression of some fertility-associated testicular genes in the rat during postnatal period could be differentially regulated by the control of the degree of DNA methylation.

A Progressive Metadata Building Methodology based on Data Visibility (데이타 가시성 기반의 점진적 메타데이타 레지스트리 구축 방법론)

  • 정동원;신동길;정은주;이정욱;서태설;백두권
    • Journal of KIISE:Computing Practices and Letters
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    • v.9 no.6
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    • pp.610-622
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    • 2003
  • Metadata Registry was developed to dynamically manage metadata and to increase interoperability between various and heterogeneous metadata. The built metadata registry can be used as a standard guideline for creation of new databases and it provides a radical data integration mechanism. However, in the situation that an enormous databases must be integrated progressively, there is a limit to the existing metadata-based approach. In case that each database has no statistical information for its use rate and the restricted cost is given to us for a unit time, existing metadata-based approaches do not provide how to select some databases to be preferentially integrated and to build a metadata registry progressively, In this paper, we propose a methodology that can create progressively metadata registries in the case. The proposed methodology is based on data visibility and hierarchical metadata registry. We also describe the system that have been developed for applying the methodology to a real domain, and then described its results.

Anti-inflammatory effect of lycopene in SW480 human colorectal cancer cells

  • Cha, Jae Hoon;Kim, Woo Kyoung;Ha, Ae Wha;Kim, Myung Hwan;Chang, Moon Jeong
    • Nutrition Research and Practice
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    • v.11 no.2
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    • pp.90-96
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    • 2017
  • BACKGROUND/OBJECTIVES: Although the antioxidative effects of lycopene are generally known, the molecular mechanisms underlying the anti-inflammatory properties of lycopene are not fully elucidated. This study aimed to examine the role and mechanism of lycopene as an inhibitor of inflammation. METHODS/MATERIALS: Lipopolysaccharide (LPS)-stimulated SW 480 human colorectal cancer cells were treated with 0, 10, 20, and $30{\mu}M$ lycopene. The MTT assay was performed to determine the effects of lycopene on cell proliferation. Western blotting was performed to observe the expression of inflammation-related proteins, including nuclear factor-kappa B ($NF-{\kappa}B$), inhibitor kappa B ($I{\kappa}B$), mitogen-activated protein kinase (MAPK), extracellular signal-related kinase (ERK), c-jun NH2-terminal kinase (JNK), and p38 (p38 MAP kinase). Real-time polymerase chain reaction was performed to investigate the mRNA expression of tumor necrosis factor ${\alpha}$ ($TNF-{\alpha}$), interleukin-1 beta ($IL-1{\beta}$), interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). Concentrations of nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) were determined via enzyme-linked immunosorbent assays. RESULTS: In cells treated with lycopene and LPS, the mRNA expression of $TNF-{\alpha}$, $IL-1{\beta}$, IL-6, iNOS, and COX-2 were decreased significantly in a dose-dependent manner (P < 0.05). The concentrations of $PGE_2$ and NO decreased according to the lycopene concentration (P < 0.05). The protein expressions of $NF-{\kappa}B$ and JNK were decreased significantly according to lycopene concertation (P < 0.05). CONCLUSIONS: Lycopene restrains $NF-{\kappa}B$ and JNK activation, which causes inflammation, and suppresses the expression of $TNF-{\alpha}$, $IL-1{\beta}$, IL-6, COX-2, and iNOS in SW480 human colorectal cancer cells.

Concept Design of Angular Deviation and Development of Measurement System for Transparency in Aircraft (항공기 투명체의 편각개념 설계 및 측정 시스템 개발)

  • Moon, Tae-Sang;Woo, Seong-Jo;Kwon, Seong-Il;Ryu, Kwang-Yeol
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.38 no.11
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    • pp.1123-1129
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    • 2010
  • Angular Deviation(AD) on transparency applied to TA-50 Aircraft deteriorates armament system's accuracy because it makes a difference in between actual and theoretical targets. In order to increase accuracy, therefore, TA-50 Aircraft measures AD on transparency and provide the measured values for the integrated mission display computer as a type of AD coefficients. This makes AD revised so that pilots can accurately see the actual target on their head-up display. In order to implement such mechanism into a real field, we develop a new device and system automatically measuring AD for the first time. We also deal with basic concept including AD induction formula as well as operating systems. As a consequence of testing the accuracy and precision for verifying reliability of the system, we got satisfactory results. In specific, the accuracy was within the resultant criterion of 1%. The precision was also satisfied with respect to the whole criteria. The system developed through this research is qualified as a military standard equipment for transparency of the canopy.