• Title/Summary/Keyword: External Factor Control

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Development of the Dynamic Model and Control Logic for the Rear Wheel Steering in 4WS Vehicle (후륜 조향 동력학 모델 및 제어 로직 개발)

  • 장진희;김상현;한창수
    • Transactions of the Korean Society of Automotive Engineers
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    • v.4 no.6
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    • pp.39-51
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    • 1996
  • In the turning maneuver of the vehicle, its motion is mainly dependent on the genuine steering characteristics in view of the directional stability for stable turning ability. The under steer vehicle has an ability to maintain its own directonal performance for unknown external disturbances to some extent. From a few years ago, in order to acquire the more enhanced handling performance, some types of four wheel steering vehicle were considered and constructed. And, various rear wheel control logics for external disturbances has not been suggested. For this reason, in this posed rear wheel control logic is based on the yaw rate feed back type and is slightly modified by an yaw rate tuning factor for more stable turning performance. And an external disturbance is defined as a motivation of the additional yaw rate in the center of gravity by an uncertain input. In this study, an external disturbance is applied to the vehicle as a form of the additional yawing moment. Finally, the proposed rear wheel control logic is tested on the multi-body analysis software(ADAMS). J-turn and double lane change test are performed for the validation of the control logic.

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A Study on Measurement and Control of position and pose of Mobile Robot using Ka13nan Filter and using lane detecting filter in monocular Vision (단일 비전에서 칼만 필티와 차선 검출 필터를 이용한 모빌 로봇 주행 위치.자세 계측 제어에 관한 연구)

  • 이용구;송현승;노도환
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.81-81
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    • 2000
  • We use camera to apply human vision system in measurement. To do that, we need to know about camera parameters. The camera parameters are consisted of internal parameters and external parameters. we can fix scale factor&focal length in internal parameters, we can acquire external parameters. And we want to use these parameters in automatically driven vehicle by using camera. When we observe an camera parameters in respect with that the external parameters are important parameters. We can acquire external parameter as fixing focal length&scale factor. To get lane coordinate in image, we propose a lane detection filter. After searching lanes, we can seek vanishing point. And then y-axis seek y-sxis rotation component(${\beta}$). By using these parameter, we can find x-axis translation component(Xo). Before we make stepping motor rotate to be y-axis rotation component(${\beta}$), '0', we estimate image coordinates of lane at (t+1). Using this point, we apply this system to Kalman filter. And then we calculate to new parameters whick make minimum error.

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Therapeutic Effects of Acupuncture and Herbal External Preparation on Healing of Deep Partial Thickness Burn Wound in Rats (심재성 2도 화상이 유발된 흰쥐의 조직 회복에 대한 침 및 한약외용제의 효과)

  • Jo, Hee-Guen;Park, Ae-Ryon;Choi, Jin-Bong
    • Journal of Korean Medicine Rehabilitation
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    • v.24 no.3
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    • pp.87-98
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    • 2014
  • Objectives The present study aimed to investigate the effects of acupuncture and herbal external preparation on wound healing procedure in a deep partial thickness burn model in rats. Methods A total of 40 male Sprague-Dawley rats were allocated into four groups with an equal number in each group: acupuncture treatment group, herbal external perparation group, Silver sulfadiazine dressing group and control group. We describe the effect of acupuncture and herbal external preparation on morphologic and histologic changes, epithelial growth factor (EGF), hematological value of the deep partial thickness burn wound in rats. Results At 21th day after wounding the wound size in acupuncture treat group and herbal external preparation group were decreased more significantly compared to control group. In addition, epidermal regeneration on acupuncture treatment was than other treatment and control group in histological finding. Hematological findings revealed that acupuncture treatment group and herbal external prepartion group was more effective than control group in reducing inflammation response induced by burn. In acupuncture treated group, neutrophil and leukocyte level were significantly decreased compared to other treatment group. Also, this study showed that EGF was obviously expressed in nascent tissue when wounds were treated with the acupuncture and herbal external preparation after injury. In particular, acupuncture treatment group had a significant increase of EGF expression in burn wound healing area when compared with the other treatment groups. Conclusions These findings suggest that acupuncture and herbal external prepration may improve burn wound healing through decreasing inflammatory reaction, increasing tissue regeneration and expression of EGF. Moreover, acupuncture treatment could be more effective in comparison with Silver sulfadiazine dressing.

Modeling and Identification of Human Mind using a Robot Which Walks Together

  • Kwon, Oh-Kyu;Park, Poo-Gyeon
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.161.2-161
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    • 2001
  • To achieve a cooperative work between human and robot, it is thought helpful to estimate the states of human mind, which originates his behavior. In this paper, human mind was considered to modify instinctive desires according to the conditions of external world surrounding the instinct. A simple human mind model was designed so that it finds a balance between instinctive desire and restriction from the external world. The external world is divided into three sub-worlds like subject´s whole body, its partner and concerned periphery. Proposed mind model has three-layers construction. Each of the layer tries to find a balance between desire and restriction from external world. In each layer, the role of finding the balance was expressed by an identical optimal control minimizing a performance index function of quadratic form with a weight factor, which is rearranged and named ...

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정부출연연구기관에서의 자금조달환경의 불확실성이 관리통제시스템에 미치는 영향 - PBS 제도 도입을 중심으로 -

  • 이민형
    • Journal of Technology Innovation
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    • v.11 no.1
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    • pp.177-193
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    • 2003
  • This paper examines empirically if the increase of funding uncertainty in government supported R&D institutes(GSRIs) in Korean cause managers to use more effective management control practices. Recently government introduced a new government R&D budget management system, based on competition, named PBS(Project Base System). Government requires GSRIs to be self-supporting and compete for funding from government. The introduction of new budget management system named PBS, has resulted in the increase of funding uncertainty in GSRIs. According to institutional theory, government organizations gain legitimacy by conforming to external expectations regarding management control practices, In contrast, contingency theory proposes that management control practices are driven by the fit between the technical features of the environment and the management control practices. The contingency literature provides that one external factor expected to motivate government managers to use more efficient control practices is the presence of competition and funding uncertainty. This paper use both theoretical perspective to develop hypotheses and examine the influence of funding environment on management control practices. Results show that the more institutionalized environment, the more managers in GSRIs rely on bureaucratic mode of control for conforming to external requirements, and the greater the funding uncertainty, the more managers use results and personal modes of control to improve research team performance.

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Exploring factors of nutrition teachers' intentions for sustainable dietary education in South Korea: an application of the theory of planned behavior

  • Eunseo Yang;Borham Yoon
    • Korean Journal of Community Nutrition
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    • v.29 no.2
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    • pp.114-128
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    • 2024
  • Objectives: The purpose of this study was to investigate the perception of nutrition teachers and the factors influencing their intention toward sustainable dietary education utilizing the theory of planned behavior (TPB). Methods: The self-administered online survey was completed by nutrition teachers in Jeollanam-do, South Korea. A total of 151 valid questionnaires were analyzed. Factor analysis and multiple regressions were employed to test the research model. Results: The study findings demonstrated that all TPB variables significantly influenced the sustainable dietary educational intention, with the degree of influence ranking as follows: external perceived behavioral control (β = 0.417), attitude (β = 0.240), internal perceived behavioral control (β = 0.207), and subjective norms (β = 0.181). For external perceived behavioral control, nutrition teachers and elementary schools exhibited higher levels compared to dietitians and middle/high schools, respectively. The participants in sustainable dietary education training programs exhibited a higher level of internal perceived behavioral control compared to those who did not participate. The highest perception levels were reported for attitude (4.26), followed by subjective norms (4.02), internal perceived behavioral control (3.67), and external perceived behavioral control (3.20). Conclusions: This study affirmed that the TPB variables elucidated the sustainable dietary educational intentions of nutrition teachers. The significant impacts of external and internal perceived behavioral control, attitude, and subjective norms on educational intentions were confirmed. Consequently, proactive support from schools and governments is essential to enhance the facilitating factors and mitigate the barriers toward sustainable dietary education in schools.

Uptake and Phytotoxicity of TNT in Onion Plant

  • Kim, Jaisoo;Yavuz Corapcioglu;Malcolm C. Drew
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.09a
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    • pp.102-106
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    • 2003
  • The uptake of $^{14}C$-2, 4, 6-trinitrotoluene (TNT) in hydroponics was studied using onion plants. Of the total TNT mass (5 $\mu\textrm{M}$ concentration), 75% was in the roots, 4.4% in the leaves, and 21% in the external solution at 2 days, The percent distribution in roots was lower with higher concentration in the external solution, but in leaves it was comparable at all concentrations (5-500 $\mu\textrm{M}$). Root concentration factor (RCF) in hydroponics was more than 85 in constant hydroponic experiment (CHE) at 5 $\mu\textrm{M}$ and 150 in non-constant hydroponic experiment (NHE) at 5 $\mu\textrm{M}$. The maximum RCF values in the hydroponic system were greater with lower solution concentration. Transpiration stream concentration factor (TSCF) values in the present study (NHE only: 0.31-0.56) were relatively similar to the values with predicted values (0.43-0.78), increasing with higher external TNT concentration. For phytotoxicity tested in hydroponics and wet paper method, 500 $\mu\textrm{M}$ was toxic to onion plant, 50 $\mu\textrm{M}$ was non-toxic for plant growth but limited the transpiration rate, and 5 $\mu\textrm{M}$ was non-toxic as control.

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The Reduction Methodology of External Noise with Segmentalized PSO-FCM: Its Application to Phased Conversion of the Radar System on Board (축별 분할된 PSO-FCM을 이용한 외란 감소방안: 함정용 레이더의 위상변화 적용)

  • Son, Hyun-Seung;Park, Jin-Bae;Joo, Young-Hoon
    • Journal of Institute of Control, Robotics and Systems
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    • v.18 no.7
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    • pp.638-643
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    • 2012
  • This paper presents an intelligent reduction method for external noise. The main idea comes from PSO-FCM (Particle Swam Optimization Fused fuzzy C-Means) clustering. The data of the target is transformed from the antenna coordinates to the vessel one and to the system coordinates. In the conversion, the overall noises hinder observer to get the exact position and velocity of the maneuvering target. While the filter is used for tracking system, unexpected acceleration becomes the main factor which makes the uncertainty. In this paper, the tracking efficiency is improved with the PSO-FCM and the compensation methodology. The acceleration is approximated from the external noise splitted by the proposed clustering method. After extracting the approximated acceleration, the rest in the noise is filtered by the filter and the compensation is added to after that. Proposed tracking method is applicable to the linear model and nonlinear one together. Also, it can do to the on-line system. Finally, some examples are provided to examine the reliability of the proposed method.

Robust adaptive control of linear time-varying systems which are not necessarily slowly varying

  • Song, Chan-Ho
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10b
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    • pp.1424-1429
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    • 1990
  • This paper presents an indirect adaptive control scheme for discrete linear systems whose parameters are not necessrily slowly varying. It is assumed that system parameters are modelled as linear combinations of known bounded functions with unknown constant coefficients. Unknown coefficients are estimated using a recursive least squares algorithm with a dead zone and a forgetting factor. A control law which makes the estimated model exponentially stable is constructed. With this control law and a state observer, all based on the parameter estimates, it is shown that the resulting closed-loop system is globally stable and robust to bounded external disturbances and small unmodelled plant uncertainties.

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The Effect of External Medium on Serum Protein of Fresh Water Fish(I) (담수산어류의 혈청단백질에 미치는 환경수의 영향(I))

  • 이용억;김익태
    • The Korean Journal of Zoology
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    • v.8 no.2
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    • pp.28-32
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    • 1965
  • It is well known that many kinds of chemical or metalic agent which were ionized or undissociated at toxified external medium and remarkable effect occurred to the fresh water fish. The effects of hydrogen ion concentration on serum protein of fresh water fish, (phycephalus argus CANTOR) had not been reported yet. In this point, authors attempted to study the changes of A/G ratio, total protein, hemoglobin, hematocrit, RBC , liver and kidney weight of snake head in the above environment. 95 snake heads were subjected to external medium with PH-4.5 and A/G ratio, hematocrit, hemoglobin, total protein, RBC, and liver & kidney weight were measured at 32.80, 15202000 and 272 hours respectively. In whole experimental period, L 1 and L2 globulin increased, on the other, albumin decreased as compare with control . Hence, the A/G ratio decreased remarkably . Though, total protein increased prominently through the whole experimental period, hematocrit, hemoglobin, RBC, increased only at 80 hours, and then decreased as compared to the control. Liver weight revealed distinctive increase at 80 hours, but no remarkable change could be seen there after. Hence, kidney weight revealed continuous rise. By these results, it may be said that as snake head were subjected to external medium with PH-4.5, this environmental factor influenced protein metabolism , blood component and organs.

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