• Title/Summary/Keyword: Control Function

Search Result 11,254, Processing Time 0.041 seconds

Indoor Temperature Control of a Heat Pump Based on Model Predictive Control Considering Energy Efficiency (에너지효율을 고려한 모델예측제어에 기초한 열펌프의 실내온도 제어)

  • 조항철;변경석;송재복;장효환;최영돈
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.13 no.3
    • /
    • pp.200-208
    • /
    • 2001
  • In indoor temperature control of a heat pump, a reduction in energy consumption is very important. However, most control schemes for heat pumps have focused only on control performance such s settling time and steady-state error. In this paper, the model predictive control (MPC) which includes the energy-related variable in this cost function is proposed. By computing the control signal minimizing this cost function, the trade-off between energy reduction and temperature control performance can be obtained. Since the MPC required the process model, the dynamic mode of a heat pump is also obtained by the system identification technique. Performance of the proposed MPC considering energy efficiency is compared with the two other control schemes. It si shown that the proposed scheme can consume less energy thant hte others in achieving similar control performance.

  • PDF

The Effect of Hand Function Training on Hand Dexterity (손 기능 훈련이 손의 기민성에 미치는 영향)

  • Jang, Chel;Lee, Jeyoung;Song, Minok
    • Journal of The Korean Society of Integrative Medicine
    • /
    • v.3 no.4
    • /
    • pp.11-21
    • /
    • 2015
  • Purpose : The purpose of this study was to provide the material about the treatment effect of hand function training and writing training being performed as a part of treatment to improve the function of the non-dominant hand of the patients whose dominant hand is damaged and thus need to improve their non-dominant hand's function. Method : During one month of November, 2013, this study randomly chose five study subjects for hand function training, five for writing training, and ten of control group from 20 normal male and female adults going to K Univ. in Busan. All study subjects fully understood all of the training course, agreed to take the test in this study, and volunteered to participate in the test. Each training was performed five times for two weeks, 30 minutes each time. For measurement, Purdue pegboard was used to look into the change of hand dexterity. To investigate an improvement in hand function through hand function training and writing training, this study conducted early evaluation before training, interim evaluation, and final evaluation. Result : First, according to the comparison of dominant hand dexterity by group and by method during a training period, the groups of hand function training and of writing training improved dominant hand dexterity more than the control group. Secondly, according to the comparison of non-dominant hand dexterity by group during a training period, the groups of hand function training and of writing training improved dexterity more than the control group. According to the comparison of non-dominant hand dexterity by method during a training period, there was no big difference in dexterity between the groups of hand function training and of writing training and the control group. But, the group of hand function training showed a further improvement. Thirdly, according to the comparison of both-hand dexterity by group and by method during a training period, the groups of hand function training and of writing training improved both-hand dexterity more than the control group. Fourthly, according to the comparison of both-hand handling ability by group and by method during a training period, the groups of hand function training and of writing training improved both-hand handling ability more than the control group. Conclusion : Given the study result, it is considered that hand function training and writing training help brain damaged patients improve their hand function for their daily activity. And it will be meaningful to research brain damaged patients' motor skills after their brain damage, and the patients who have low abilities of visual perception and cognition. In the future, it will be necessary to secure more study subjects and perform systematic training during a sufficient test period.

Effects of Posture Correction Training on Pulmonary Function with Turtle Neck Syndrome (자세교정훈련이 거북목증후군의 폐기능에 미치는 영향)

  • Jang, Cheul
    • Journal of The Korean Society of Integrative Medicine
    • /
    • v.9 no.1
    • /
    • pp.183-192
    • /
    • 2021
  • Purpose : The purpose of this study was to investigate the impact of postural correction training on pulmonary function on 28 college students suspected of turtle neck syndrome, and the following conclusions were obtained. Methods : Turtle neck syndrome suspicion 28 person were randomly divided into a posture training group (n = 14) and group that does not perform posture training (n = 14). Respiratory function was measured by SPIROVIT SP-1 and respiratory gas analyzer. The posture training group performed balloon blowing and stair climbing after 20 minutes of posture training, and the group without posture training carried out balloon blowing training and stair climbing. Five times a week and for two weeks. Results : 1. The comparison of the FVC before and after experiments caused by balloon blowing showed a higher level of effortful pulmonary function in the control group than in the experimental group. 2. Comparison of PEFs before and after the experiment by balloon blowing showed that the experimental group's peak flow rate was higher than that of the control group. 3. Comparison of the FIVC before and after experiments with balloon blowing showed that the comparison of the FIVC showed a higher level of effortless intake pulmonary function in the control group than in the experimental group. 4. The comparison of the maximum ventilation volume(VE) before and after the experimental gas measurement showed that the maximum ventilation rate of the experimental group was higher than that of the control group. 5. The comparison of pre-test and post-test heart rate(HR) by breath gas measurement showed that the heart rate of the control group was higher than that of the experimental group. Conclusion : the results of this study showed that postural correction training, balloon blowing training, and stair climbing could have a positive impact on improving pulmonary function. However, the two-week experiment conducted five times a week showed an increase in pulmonary function, but it was difficult to see the effect due to the short study period. Therefore, it is hoped that later studies will be conducted more systematically on the effects of breathing exercises on improving pulmonary function after post-postural correction training for patients with pulmonary function problems.

Adaptive sliding-mode tracking control in the presence of unmodeled dynamics

  • Cho, Seung-Ho
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1994.10a
    • /
    • pp.267-270
    • /
    • 1994
  • To increase the robustness of tile feedforward tracking control system, a new discrete time sliding function has been defined and utilized for the formulation of control law, In adaptive case the robustness is achieved by using both a normalized gradient algorithm with deadzone and a sliding function-based nonlinear feedback, while in nonadaptive case by using only a sliding function-based nonlinear feedback.

  • PDF

Sliding Mode Control with Nonlinear Interpolation in Variable Boundary Layer

  • Kim, Yookyung;Jeon, Gijoon
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2002.10a
    • /
    • pp.35.1-35
    • /
    • 2002
  • $\textbullet$ Sliding mode control (SMC) with nonlinear interpolation in variable boundary layer (VBL) is proposed $\textbullet$ A sigmoid function is used for nonlinear interpolation in VBL. $\textbullet$ The Parameter of the sigmoid function is tuned by fuzzy controller $\textbullet$ The choice of parameter for the sigmoid function is guided by FC. $\textbullet$ The parameter is continuously updated as boundary layer thickness varies. $\textbullet$ The proposed method hasbetter tracking performance than the conventional linear interpolation $\textbullet$ To demonstrate its performance the proposed control algorithm is applied to a nonlinear system.

  • PDF

An Edge-Based Algorithm for Discontinuity Adaptive Image Smoothing (에지기반의 불연속 경계적응 영상 평활화 알고리즘)

  • 강동중;권인소
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2000.10a
    • /
    • pp.273-273
    • /
    • 2000
  • We present a new scheme to increase the performance of edge-preserving image smoothing from the parameter tuning of a Markov random field (MRF) function. The method is based on automatic control of the image smoothing-strength in MRF model ing in which an introduced parameter function is based on control of enforcing power of a discontinuity-adaptive Markov function and edge magnitude resulted from discontinuities of image intensity. Without any binary decision for the edge magnitude, adaptive control of the enforcing power with the full edge magnitude could improve the performance of discontinuity-preserving image smoothing.

  • PDF

A New Variable-Structure Position Control for DC Motor Using Fuzzy Logic (퍼지논리를 이용한 직류전동기용 가변구조 위치제어시스템)

  • 이상래;이광원
    • The Transactions of the Korean Institute of Electrical Engineers
    • /
    • v.41 no.6
    • /
    • pp.625-632
    • /
    • 1992
  • This paper presents a new dc-motor position control approached by Variable Structure System. In order to eliminate a steady-state position error, we propose a switching function composed of position error, velocity, and current ripple. The switching function has an advantage compared to other ones. To determine the control signal voltage, we use a fuzzy logic method. The simulation results show expected performances.

  • PDF

POLYNOMIAL FUNCTION BASED GUIDANCE FOR IMPACT ANGLE AND TIME CONTROL

  • KIM, TAE-HUN
    • Journal of the Korean Society for Industrial and Applied Mathematics
    • /
    • v.19 no.3
    • /
    • pp.305-325
    • /
    • 2015
  • In this paper, missile homing guidance laws to control the impact angle and time are proposed based on the polynomial function. To derive the guidance commands, we first assume that the acceleration command profile can be represented as a polynomial function with unknown coefficients. After that, the unknown coefficients are determined to achieve the given terminal constrains. Using the determined coefficients, we can finally obtain the state feedback guidance command. The suggested approach to design the guidance laws is simple and provides the more generalized optimal solutions of the impact angle and time control guidance.

Effects of Mask Wearing Due to COVID-19 on Cardiovascular Function in Treadmill Exercise (COVID-19로 인한 마스크 착용이 보행 속도에 따라 심혈관계 기능에 미치는 영향)

  • Ki-Won, Nam;Dong-Yel, Seo
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.17 no.4
    • /
    • pp.37-43
    • /
    • 2022
  • PURPOSE: To find out how wearing a mask due to COVID-19 affects cardiovascular function as the pace of walking changes. METHODS: Forty-nine college students (27 men, 22 women) were subjected to treadmill exercises without masks (Group I) and wearing masks (Group II). The body temperature, heart rate, oxygen saturation, and blood pressure were measured to determine the changes in cardiovascular function. These parameters were measured at rest (Control I), low-intensity (Control II), medium-intensity (Control III), and high-intensity (Control IV) before and after exercise. RESULTS: Significant differences in heart rate were observed between Control III and Control IV, and a significant difference in oxygen saturation was noted in Control IV. Significant differences in the exercise intensity change in Group II were as follows: Body temperature was Control IV compared to Control I and Control II, heart rate was Control III and Control IV compared to Control I and Control II, and Control IV compared to Control III. The heart rate was Control III and Control IV compared to Control I and Control II, Control IV for Control III, oxygen saturation was Control IV compared to Control I, blood pressure was Control II and Control III and Control IV compared to Control I, and Control IV compared to Control II. CONCLUSION: Exercising when wearing a mask affects the cardiovascular system. Therapists should consider the patient's condition when setting the exercise intensity. In particular, therapists should be more careful when setting the exercise intensity of patients with cardiovascular disease.

Clinical Application of AR System in Early Rehabilitation Program After Stroke: 2 Case Study

  • An, Chang Man;Kim, Dae Hyun
    • The Journal of Korean Physical Therapy
    • /
    • v.31 no.3
    • /
    • pp.141-146
    • /
    • 2019
  • Purpose: To investigate the effect of an augmented reality (AR) system on muscle strength and function level of the paretic lower limb and the balance ability in the early rehabilitation program of acute stroke patients. Methods: The participants (30 or fewer days after stroke) were randomly assigned to receive intervention with an early rehabilitation program using an AR system (n=1) or an early rehabilitation program consisting of functional electrical stimulation and tilt table use (n=1). Patients in both subjects received interventions 4-5 times a week for 3 weeks. Results: In the paretic limb muscle strength, AR subject was increased from 15 to 39.6 Nm and Control subject was increased from 5 to 30.2 Nm. The paretic limb function of AR subject motor function was increased from 8 to 28 score and Control subject motor function was increased from 6 to 14 score. But sensory function was very little difference between the two subjects (AR subject: from 4 to 10 score, Control subject: from 3 to 10 score). In the balance ability, AR subject had more difference after intervention than control subject (AR subject: 33 score, Control subject: 22 score). Conclusion: The early rehabilitation program using the AR system showed a slightly higher improvement in the motor function of the paretic lower limb and balance ability measurement than the general early rehabilitation program. The AR system, which can provide more active, task-oriented, and motivational environment, may provide a meaningful environment for the initial rehabilitation process after stroke.