• Title/Summary/Keyword: 2 order system

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The required conditions for healthcare system sustainability (보건의료체계 지속가능성의 필수 조건들)

  • Bae, Jong-Myon
    • Journal of Medicine and Life Science
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    • v.16 no.2
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    • pp.52-54
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    • 2019
  • While sustainability is seen in terms of social, economic and environmental dimensions, securing longterm financial costs and planning long-term strategic perspective among policy-makers are needed to maintain a healthcare system sustainability. Thus, the networking and cooperation between policy makers and health care workers should be tightened and strengthened in order to keep and enhance the healthcare system sustainability.

Sliding Mode Control for an Electric Power Steering System in an Autonomous Lane Keeping System (자동 차선 유지 시스템의 전기식 파워 조향 시스템을 위한 슬라이딩 모드 제어기)

  • Yu, Jun Young;Kim, Wonhee;Son, Young Seop;Chung, Chung Choo
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.2
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    • pp.95-101
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    • 2015
  • In this paper, we develop a sliding mode control for steering wheel angle control based on torque overlay in order to resolve the problem of previous methods for Electric Power Steering (EPS) systems in the Lane Keeping System (LKS) of autonomous vehicles. For the controller design, we propose a 2nd order model of the electric power steering system in an autonomous LKS. The desired state model is designed to prevent a rapid change of the steering wheel angle. The sliding mode steering wheel angle controller is developed for the robustness of the disturbance. Since the proposed method is designed based on torque overlay, torque integration with basic functions of the EPS system for the steering wheel angle control is available for the driver's convenience. The performance of the proposed method was validated via experiments.

A Monitoring System of Ensemble Forecast Sensitivity to Observation Based on the LETKF Framework Implemented to a Global NWP Model (앙상블 기반 관측 자료에 따른 예측 민감도 모니터링 시스템 구축 및 평가)

  • Lee, Youngsu;Shin, Seoleun;Kim, Junghan
    • Atmosphere
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    • v.30 no.2
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    • pp.103-113
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    • 2020
  • In this study, we analyzed and developed the monitoring system in order to confirm the effect of observations on forecast sensitivity on ensemble-based data assimilation. For this purpose, we developed the Ensemble Forecast Sensitivity to observation (EFSO) monitoring system based on Local Ensemble Transform Kalman Filter (LETKF) system coupled with Korean Integrated Model (KIM). We calculated 24 h error variance of each of observations and then classified as beneficial or detrimental effects. In details, the relative rankings were according to their magnitude and analyzed the forecast sensitivity by region for north, south hemisphere and tropics. We performed cycle experiment in order to confirm the EFSO result whether reliable or not. According to the evaluation of the EFSO monitoring, GPSRO was classified as detrimental observation during the specified period and reanalyzed by data-denial experiment. Data-denial experiment means that we detect detrimental observation using the EFSO and then repeat the analysis and forecast without using the detrimental observations. The accuracy of forecast in the denial of detrimental GPSRO observation is better than that in the default experiment using all of the GPSRO observation. It means that forecast skill score can be improved by not assimilating observation classified as detrimental one by the EFSO monitoring system.

Numerical Analysis of Optimum Air-Layer Thickness in a Double Glazing Window (이중창 공기층의 최적두께에 관한 수치해석)

  • Hwang Ho June;Choi Hyoung Gwon
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.17 no.2
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    • pp.191-199
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    • 2005
  • Double pane window system, in which an air layer with a finite width is filled between glasses, is used in order to increase the insulation efficiency. In the present study, a conjugate heat transfer problem of a double pane window system has been studied numerically in order to investigate the effect of an air layer on the heat transmittance of the double pane window system using a finite element method based on P2P1 basis function. In this study on the conjugate heat transfer of a double pane window system, numerically predicted Nusselt numbers with or without conjugate heat transfer effect have been compared with an available existing empirical formula. It has been found that a Nusselt number from an existing formula for an enclosed space is different from that obtained from the present conjugate heat transfer analysis mainly due to the effects of a very high aspect ratio and conjugate heat transfer mechanism. Furthermore, it has been shown that the numerically estimated optimal air thickness of the double pane window system with conjugate heat transfer effect is a little bit longer than that obtained without considering conjugate heat transfer effect.

Dynamic Analysis of Mindfulness and Therapeutic Relationship using System Dynamics (시스템다이내믹스를 활용한 마음챙김과 치료관계 간의 동태적 분석)

  • Choi, Yeon-Hee
    • Korean System Dynamics Review
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    • v.17 no.3
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    • pp.121-143
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    • 2016
  • The purpose of this study to analyze the effect of Mindfulness on the Therapeutic Relationship using System Dynamics. The biggest factor in psychotherapy's treatment outcome is the Therapeutic Relationship including the quality of the therapist (empathy, therapeutic presence) and therapy alliance. Mindfulness practice can facilitate the therapeutic relationship. In order to analyze the therapeutic relationship, I measure FFMQ(Five Facet Mindfulness Questionnaire), Empathy, Therapeutic presence and Therapy alliance. Participants consist of 55 mental health professionals (doctor, psychologist, psychiatrist, counselor, social worker). The result of the study will be explained. First, with the causal loop diagram research, I analyze how mindfulness can influence the quality of therapist and therapy alliance. The result of literature research indicate that mindfulness increase therapist's empathy, congruence, therapeutic presence, flow, therapy alliance. And then mindfulness reinforces the ability of therapeutic relationship. Secondly, through the real data research and simulation analysis, mindfulness practicing period (year and hour a day) of therapist is studied. The result of the therapist experiencing mindfulness practice period is over 5 years and the daily hours of practice is 2 - 2.5 hours in order to enhance the therapeutic relationship. After reviewing the result of the research it is important to understand the practicing period and daily practice of mindfulness. With daily practice and time, the level of mindfulness will increase and influence positively the therapeutic relationship between therapist and client.

PWM-Based Sliding Mode Controller for Three-Level Full-Bridge DC-DC Converter that Eliminates Static Output Voltage Error

  • Liu, Jilong;Xiao, Fei;Ma, Weiming;Fan, Xuexin;Chen, Wei
    • Journal of Power Electronics
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    • v.15 no.2
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    • pp.378-388
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    • 2015
  • This paper proposes a pulse width modulation (PWM)-based sliding mode controller (SMC) for a full-bridge DC-DC converter that can eliminate static output voltage error. Hysteretic SMC in DC-DC converter does not have a fixed switching frequency, and applying hysteretic SMC to full-bridge converters is difficult. Fixed-frequency SMC, which is also called PWM-based SMC, based on equivalent control overcomes these shortcomings. However, the controller order reduction in equivalent control in PWM-based SMC causes static output voltage error. To resolve this issue, an integral item is added to the PWM-based SMC. Sliding mode coefficients are designed by applying a standard second-order system to the sliding mode surface. The effect of adding an integral item on the controller is analyzed, and an integral coefficient design method is proposed. Experiment results on a three-level full-bridge DC-DC converter verify the control scheme and design method proposed in this paper.

Studies of Nonstoichiometry and Physical Properties of the Perovskite $Sm_{1-x}Sr_xCoO_{3-y}$ System

  • 강진우;류광현;여철현
    • Bulletin of the Korean Chemical Society
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    • v.16 no.7
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    • pp.600-603
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    • 1995
  • A series of samples in the Sm1-xSrxCoO3-y(x=0.00, 0.25, 0.50, 0.75 and 1.00) system has been prepared at 1200 ℃ under ambient atmosphere. The X-ray diffraction patterns of the samples with x=0.00 and 0.25 are indexed with orthorhombic symmetry like GdFeO3 and x=0.50 appears to be perfectly cubic. In the tetragonal system (x=0.75), the structure is similar to that of SrCoO2.80. The composition of x=1.00, SrCoO2.52, shows the brownmillerite-type structure. The reduced lattice volume is increased with x value in this system. The chemical analysis shows the τ value (the amount of the Co4+ ions in the system) is maximized at the composition of x=0.50. Nonstoichiometric chemical formulas are determined by the x, τ and y values. The electrical conductivity has been measured in the temperature range of 78 to 1000 K. The activation energy is minimum for those of x=0.25 and x=0.50 with metallic behavior. First-order semiconductor-to-metal transition of SmCoO3 is not observed. Instead, a broad, high-order semiconductor-to-metal transition is observed. In general, the effective magnetic moment is increased with increasing τ values at low temperature. At high temperature, the magnetic moment is maximum for that of x=0.00. The 3d-electrons are collective and give ferromagnetism in x=0.50.

Cloth Product Recognition based on Siamese Network with Body Region Extraction method

  • Budiman, Sutanto Edward;Kurniawan, Edwin;Lee, Seung Heon;Lee, Jae Seung;Lee, Suk-Ho
    • International journal of advanced smart convergence
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    • v.11 no.2
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    • pp.128-134
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    • 2022
  • Nowadays, people consume a lot of content such as web dramas or K-pop videos through mobile devices such as smartphones, and the market for indirect advertisements through these web dramas or K-pop videos is also increasing every year. In order to lead to the immediate purchase of indirect products in web dramas, a system that allows consumers to purchase immediately at the time the products appear in the drama is needed. In this paper, we propose a system to allow viewers to purchase products worn by celebrities immediately when viewers see and click on them. When a user clicks on a video, it recognizes the product worn by the celebrity, and displays information on the screen on the most similar product corresponding to the recognized product, allowing them to go to the seller's site where they can purchase it. In order for such a system to operate stably, a pose estimation and siamese network-based system is proposed. The proposed system will primarily be released as a streaming service in the form of an app or web page that connects the products in web dramas or other K-pop video contents screened on the mobile with e-commerce. Furthermore, in the future, the technology is expected to be used globally in various industries such as smart mobility and display kiosks.

Implementation of School Asserts Management Utilizing the 13.56MHz/2.45GHz RFID (13.56MHz/2.45GHz RFID를 활용한 학교 자산 관리 시스템 구현)

  • Ahn, Sung Soo;Joh, Beom Seok;Kim, Ki Yun
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.7 no.4
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    • pp.67-73
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    • 2011
  • We developed a RFID system to effective management and monitoring for school assert. In this paper, RFID system implemented a two way which are control to 13.56MHz for in/outbound order and 2.45GHz for positioning tracking and monitoring. We also make up the contents and database utilizing the labview tool in pc. In addition, the developed system can obtain simultaneously the information from several RFID reader at real time so that it is possible to track the position system, the path moving and the status of asserts in the school. Especially, 2.45GHz system has a function to prevent a assert theft. It is observed from the various and practical experiment that the proposed system is useful for assert management and monitoring.

Study for Tracking Control of Autonomous Underwater Vehicle (AUV의 궤적제어에 관한 연구)

  • 유휘룡;김성근;김상봉
    • Journal of Ocean Engineering and Technology
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    • v.8 no.2
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    • pp.56-63
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    • 1994
  • This paper presents a design method of multivariable robust servo system for tracking control system for AUV(Autonomous Underwater Vehicle). In order to obtain the basic data for the design of the tracking control system, the control algorithm is evaluated in the view of computer simulation results. The tracking control is carried out for an AUV with 2 main thrusters, 2 side thrusters and 2 thrusters for the movement to up-down direction. The results of computer simulation show that the proposed multivariable servo system design method is an efficient method for the control performance of tracking control system of AUV under severe underwater environment.

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