Active control of a nonlinear and hysteretic building structure with time delay

Liu, Kun,Chen, Long-Xiang,Cai, Guo-Ping Techno-Press 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.40 No.3

Time delay inevitably exists in active control systems, and it may cause the degradation of control efficiency or instability of the systems. So time delay needs to be compensated in control design in order to eliminate its negative effect on control efficiency. Today time delay in linear systems has been more studied and some treating methods had been worked out. However, there are few treating methods for time delay in nonlinear systems. In this paper, an active controller for a nonlinear and hysteretic building structure with time delay is studied. The nonlinear and hysteretic behavior of the system is illustrated by the Bouc-Wen model. By specific transformation and augmentation of state parameters, the motion equation of the system with explicit time delay is transformed into the standard state space representation without any explicit time delay. Then the fourth-order Runge-Kutta method and instantaneous optimal control method are applied to the controller design with time delay. Finally, numerical simulations and comparisons of an eight-story building using the proposed time-delay controller are carried out. Simulation results indicate that the control performance will deteriorate if time delay is not taken into account in the control design. The simulations also prove the proposed time delay controller in this paper can not only effectively compensate time delay to get better control effectiveness, but also work well with both small and large time delay problems.

Active control of a nonlinear and hysteretic building structure with time delay

Kun Liu,Long-Xiang Chen,Guo-Ping Cai 국제구조공학회 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.40 No.3

Time delay inevitably exists in active control systems, and it may cause the degradation of control efficiency or instability of the systems. So time delay needs to be compensated in control design in order to eliminate its negative effect on control efficiency. Today time delay in linear systems has been more studied and some treating methods had been worked out. However, there are few treating methods for time delay in nonlinear systems. In this paper, an active controller for a nonlinear and hysteretic building structure with time delay is studied. The nonlinear and hysteretic behavior of the system is illustrated by the Bouc-Wen model. By specific transformation and augmentation of state parameters, the motion equation of the system with explicit time delay is transformed into the standard state space representation without any explicit time delay. Then the fourth-order Runge-Kutta method and instantaneous optimal control method are applied to the controller design with time delay. Finally, numerical simulations and comparisons of an eight-story building using the proposed time-delay controller are carried out. Simulation results indicate that the control performance will deteriorate if time delay is not taken into account in the control design. The simulations also prove the proposed time delay controller in this paper can not only effectively compensate time delay to get better control effectiveness, but also work well with both small and large time delay problems.

Dual source을 이용한 관상 동맥 전산화 단층촬영에서 심장 박동수와 monitoring delay time의 상관 관계에 대한 연구

장재인(Jae In Chang) 대한CT영상기술학회 2015 대한CT영상기술학회지 Vol.17 No.2

목적 : 심장CT에서 Coronary artery검사 시 협착 유무를 판정하기 위해서는 ECG gating외에 조영제의 사용은 필수적이다. 높은 대조도를 얻기 위해서는 조영제 주입 후 촬영시작 지연시간(monitoring delay time)을 결정하는 것이 중요하며, 개인마다 촬영시작 지연시간이 다르기 때문에 적정한 시간을 찾기 위하여 덩어리 추적방법 (bolus tracking)이 주로 사용되고 있다. 이때 Triggering되기 까지 요구되는 지연 시간(delay time)를 일률적으로 사용하고 있는 것이 대부분이며 이렇게 함으로써 환자에게 주어지는 선량이증가될 수 있다. 본 연구에서는 ECG gating을 통해 획득한 심장의 박동수가 촬영시작 지연시간에 어떤 영향이 있는지 알아보고 정확한 지연 시간을 찾는 것이 선량감소에 영향을 줄 수 있는지 알아보고자 한다. 대상 및 방법 : 2014년 07월부터 2014년 09월까지 Dual source CT를 이용하여 관상동맥 검사를 시행한 환자 100명을 대상으로 하였고 평균 연령은 55.5(29~85세)이고, 그 중 여성이 33명 이었다. 사용된 CT장비는 Somatom Definition (Siemens Health care, Germany)O이며, 덩어리 추적방법 (Bolus tracking)을 사용하여 상행 대동맥에 관심영역(ROI)을 설정한 후 이 영역의 HU값이 100을 넘게 되면 촬영이 시작되게 하였다. 검사 시작 전 심전도를 이용한 동조화에서 심 박동수를 측정 하였으며, Ca scoring에서는 환자가 심 흡기된 상태에 촬영하며 심 박동수를 측정 하였다. 그리고, 조영제가 주입되면서 검사가 진행 되는 동안의 심 박동수와 조영제가 들어간 후 scan이 시작된 시간을 측정하여 비교 분석하였다. 결과 : 검사 시작 전 심 박동수는 평균 69.2(101~44)회, Ca scoring 심 박동수는 평균 63.3(105~44)회로 5.6회 낮아졌다. 조영제 주입 후 측정된 심 박동수는 평균 61.1(97~36)회로 Ca scoring 심 박동수보다 2.5회 낮아졌다. 검사가 시작된 시간은 평균 17.15(11.1~24.2)초였다. 심 박동수가 36~49회는 8명으로 scan delay time이 평균18.7(15.2~21.1)초였고, 50~59회는 43명으로 평균 17.9(12.2~24.1)초, 60~69회 33명 평균 16.7(11.1~23.1)초, 70~79회 10명 평균 14.7(13.1~17.3)초, 80~89회는 5명으로 평균 13.7(12.2~16)초였다. 결론 : CT 관상동맥 검사 시 심 흡기에 검사를 진행하는 것이 심 박동수를 낮출 수 있고 이것은 움직임을 최소화 하여 좋은 해상도를 얻을 수 있다. 조영제 주입 후 심 박동수가 낮을 수록 촬영시작 지연시간이 길게 나타났으며, 지연시간이 1초 증가 때마다 CTDIvol 1.71mGy가 증가하는 것으로 나타났다. 검사 시 환자의 심 박동수에 따라 Triggering되기 까지 요구되는 지연 시간(delay time)을 조절 함으로써 환자에게 주어지는 위해 선량을 낮출 수 있을 것으로 사료된다. Purpose : High contrast is required for Coronary Artery CT. For this reason, it is important to determine the monitoring delay time after injection of contrast agents. Bolus tracking is used because appropriate monitoring delay time varies from individual to individual. Purpose of this study was to find out it monitoring delay time is affected by heart rate and accurate delay time contributes to dose reduction. Materials and Methods: From July to September 2014, 100 patients (67 men, 33 women), ranging in age from 29 to 85 years (mean, 55.5 years), underwent coronary artery CT using a dual source CT machine (Somatom Definition Flash, Siemens Health care, Germany). We set a region of interest (ROI) on ascending aorta using bolus tracking and started a CT scan when the value of ROI was over 100 HU. Heart rate and monitoring delay time were measured and comparatively analyzed. Results : Mean heart rates dropped by 5.6 in inspiration states. Mean heart rate was 69.2 (101~44) and 63.3 (105~44) before CT exams and during Ca scoring, respectively. After injecting contrast agents, mean heart rate 61.1 (97~36) dropped by 2.5 compared with that of Ca scoring. Starting scan time was 17.15 seconds on average (11.1~24.2 seconds). Average scan delay time according to the heart rate was as follows: 18. 7 (15.2~21.1) seconds for eight patients with heart rate 36-49, 17.9 (12.2~24.1) seconds for 43 patients with heart rate 50~59, 16.7(11.1~23.1) seconds for 33 patients with heart rate 60~69, 14.7 (13.1~17.3) seconds for 10 patients with heart rate 70~79, and 13.7 (12.2~16) seconds for five patients with heart rate 80~89. Conclusions : Monitoring delay time after contrast agents was longer in patients with lower heart rate. Value of CTDIvol increased by 1.71 mGy as 1 second of delay time increased. We can reduce radiation dose on patients by adjusting delay time according to their heart rate.

Measurement of Delay Time in Communication Channels by Anfis

Seyed Mohammad Amir Hosseinipa 제어로봇시스템학회 2008 제어로봇시스템학회 국제학술대회 논문집 Vol.2008 No.10

The use of teleoperation in remote locations allows humans to extend their capabilities to distant and hazardous environments. Although safer for the operator, this extension of capabilities comes at a price. Due to communication across great distances, experiencing delay times of up to several milliseconds is common. In teleoperation systems, delay time in communication channel may distort the signals, and can lead to system instability. So that any delay time in the human/robot interaction can significantly degrade the effectiveness of operator control. By prediction of delay time in the Internet, we can use new structures for creating high performance systems in teleportation systems. This paper describes a new method for prediction of delay time in the Internet. An Anfis is proposed for the prediction of delay time. By using measured data (delay time between two universities) in Transmission Control protocol (TCP), the Anfis was trained. Then, using validation data, the performance of the Anfis was evaluated. It is shown that this Anfis can predict delay time based on their proper inputs.

시간지연상의 후회에 영향을 미치는 조절변수에 관한 연구

초설,김경민 경남대학교 산업경영연구소 2016 지역산업연구 Vol.39 No.4

Previous studies on consumers' regret and time delay have been issued as there have been positive or negative effects of time delay in marketing. Based on these researches, This study has the purpose that the individual variable of self-efficiency and the context effect of evaluation mode were examined in this study. Hypotheses were made accordingly and experiments were followed by them. In the hypothesis 1, the experimental design of 2(time delay: no delay/time delay)×2(self-efficiency: low self-efficiency/high self-efficiency) was employed. The experimental design of 2 (time delay: no delay/time delay) × 2 (evaluation mode: Joint evaluation/Separate Evaluation) was made in the hypothesis 2. The interaction effects between time delay and self-efficiency were evaluated in the hypothesis 1. The interaction effect in each variable was significant statistically. In the hypothesis 2, the interaction between time delay and evaluation mode was investigated. It was significant among variables in the interaction effect. These results provide promising solution to the argument for the time delay effect and regret. In addition to this, joint evaluation is strongly recommended since time delay marketing has been utilized practically for the release of the new product. Customers need many related information to minimize their regret. For boosting their positive action, the easiness of product usage and high self-efficiency are critical. 제품선택과 사용간의 시간지연에 관한 선행연구들은 시간지연효과가 마케팅에서 긍정적 혹은부정적인 효과를 제각기 주장하여 논란이 있어왔다. 이에 대해 본 연구는 이러한 긍정적 부정적효과가 상존하는 이유로 조절변수의 존재로 예상을 하고 문헌연구를 통해 개인 특성 변수인 자기효능감과 상황맥락효과인 평가모드를 제시하였다. 이에 관련 가설들을 설정하였고 검증을 위해 실험을 실시하였다. 가설 1은 2(시간지연: 무지연/유지연) × 2(자기효능감: 저효능감/고효능감)집단 간 설계를 가설 2는 2(시간지연: 무지연/유지연) × 2(평가모드: 공동평가JE/개별평가SE)의 설계를 하여 연구를 진행하였다. 가설 1은 시간지연과 자기효능감의 상호작용을 살펴보았다. 각 변수간의 상호작용효과는 유의한 것으로 나타났다. 가설 2는 시간지연과 평가모드의 상호작용을 살펴보았다. 각 변수간의 상호작용효과는 유의한 것으로 나타났다. 이러한 연구결과는 그간의 시간지연효과와 후회의 연구결과의 논란을 해결한점에서 학문적 시사점이 있다고 하겠다. 아울러 실무적으로 신제품 출시에 있어서 시간지연 마케팅 전략이 많이활용되고 있는바 신제품 예약후 사용시까지 후회를 줄이기 위해서는 자기효능감이 높아질 수 있도록 즉, 능동적 행동을 유발 할수 있도록 관련정보를 제공하여 제품의 쉬운사용 등을 지속적으로고객에 노출시켜야 할 것이고 아울러 경쟁제품과 비교(공동비교) 역시 요구된다고 하겠다.

기혼여성의 결혼 및 출산시기 결정에 영향을 미치는 요인에 관한 연구

박다은,유계숙 한국아동가족복지학회 2011 한국가족복지학 Vol.16 No.2

The purpose of this study was to identify the delaying and advancing factors of marriage and fertility timing among married women living in Seoul and Gyeonggi-do. We also examined sociodemographic differences in the levels of those factors. Data were collected from 393 married women who were first married or gave birth to more than one child between 2006 and 2009. The sampling procedure was designed to obtain comparisons between delaying and advancing groups of their marriage, first, and second childbirth timing. The major findings of this study were as follows: The principal component analyses extracted 5 advancing factors of marriage timing and 5 delaying factors of first childbirth timing. This study also found 6 respective factors of delaying marriage timing, advancing first childbirth timing, and both of delaying and advancing second childbirth timing. The results of the analysis of sociodemographic differences in the levels of the extracted factors were as follows: There were significant differences in the levels of the delaying factors of advancing groups of the marriage significantly differed in their levels of the advancing factors of the marriage timing. The results also showed significant differences in the levels of the delaying and advancing factors of first childbirth timing according to respondents' family income and the timing of marriage and first childbirth. Finally, there were significant differences in the levels of the delaying and advancing factors of second childbirth timing according to the educational levels of husbands, family income, and women's marriage, first, and second childbirth timing. These results are discussed in relation to the implications of policies in response to low fertility. 본 연구는 기혼여성의 결혼 및 첫째자녀와 둘째자녀 출산시기 결정에 영향을 미치는 요인이 무엇인지 파악하고, 이러한 요인이 인구사회학적 특징에 따라 어떠한 차이를 나타내는지 살펴보았다. 연구대상은 서울․경기도에 거주하며 2006-2009년 사이에 결혼(초혼)이나 한명 이상의 자녀출산을 경험한 기혼여성 393명이며, 분석을 위해 연구대상을 ‘결혼집단’, ‘첫째자녀 출산집단’, ‘둘째자녀 출산집단’으로 구분하였다. 분석방법으로 주성분분석과 t-test, One way ANOVA를 실시하였으며, 주요 분석결과는 다음과 같다. 먼저, 조혼요인과 첫째자녀 출산지연 요인은 각각 5개의 하위요인이 도출되었고, 만혼요인과 첫째자녀 조기출산요인, 둘째자녀 출산지연요인 및 조기출산요인은 각각 6개의 하위요인이 도출되었다. 이 중, 만혼요인은 부인학력, 남편학력, 가구소득에 따라, 조혼요인은 결혼시기에 따라 유의미한 차이가 나타났다. 다음으로 첫째자녀 출산지연요인은 가구소득, 결혼시기, 첫째자녀 출산시기, 결혼전후 경력단절여부에 따라, 첫째자녀 조기출산요인은 초혼시기, 첫째자녀 출산시기, 결혼전후 경력단절여부에 따라 유의미한 차이가 나타났다. 마지막으로, 둘째자녀 출산지연요인은 부인 학력, 남편 학력, 가구소득, 결혼시기, 첫째자녀 출산시기, 둘째자녀 출산시기에 따라, 둘째자녀 조기출산요인은 남편 학력, 가구소득, 초혼시기, 첫째자녀 출산시기, 둘째자녀 출산시기에 따라 유의미한 차이가 나타났다. 본 연구결과는 여성의 결혼 및 자녀출산시기를 앞당기기 위한 정책적 방안을 모색하는데 유용한 시사점을 제공할 것이다.

국제건설계약에서 완공의 지연 - 방해이론(Prevention Principle)과 Time-Bar 조항 -

정홍식 국제거래법학회 2013 國際去來法硏究 Vol.22 No.2

This article addresses the issue of whether liquidated damages for delayed performance can be enforced against a contractor for periods of delay caused by the owner, and for which the contractor cannot obtain extensions of time due to the operation of time bar provisions in the extension time clause. The former is in regard to the so called “prevention principle,” and the latter is an effect of time‐bar clause. This issue has been the subject of considerable judicial and other comments in the United Kingdom and Australia. With respect to the prevention principle, an owner will lose the right to claim liquidated damages if some of the delay is due to its own, employees’ or agents’ defaults, unless (i) the extension of time clause, strictly construed, allows for extensions to be granted for delays caused by acts or defaults of the owner; and (ii) an extension has been validly granted thereunder. This will be the case even if the owner’s delays form only part of the total delay. The court will not seek to apportion delay, at least when considering enforceability of the liquidated damages clause. If the liquidated damages clause is held inoperative because of the application of this principle, the owner will still be entitled to sue the contractor for any general law damages that it can prove flow from the contractor’s default. While it is easy to state the prevention principle in general terms, it is more difficult to identify just what “acts or omissions” of the owner will bring that principle into operation. The broadest view – namely, that any act, regardless of its fault element, will be sufficient to enliven the prevention principle – is well supported by the relevant authority. Notice provisions are common in construction contracts. A question in relation to a clause requiring notification within a specified time of claims for extension of time is whether compliance with the notice is a condition precedent to the entitlement to an extension of time. Another question is whether time‐bar clauses are effective as a complete defense to contractors’ claims that are not submitted in accordance with the express notice provisions. This article further considers the legal tools used to undermine such clauses and focuses on the jurisprudential conflict between such clauses and the prevention principle. It concludes that the real issue is not the tension between the time bar clause and the prevention principle, but one between the time bar clause and the “freedom of contract” doctrine. This is because an analysis of the case law tends to support the view, both, that the prevention principle is not a rule of law, but a rule of construction.

급성 심근경색증 환자에서 혈전용해요법의 시간지연에 영향을 미치는 요인

정진옥,김윤철,성보영,김준경,전준용,류정곤,성인환,전은석 대한순환기학회 1997 Korean Circulation Journal Vol.27 No.8

D.D.D. 형 인공심박동기 시술 환자에서 심방심실 연속자극간격 변화가 수축기와 이완기에 미치는 영향

이만영(Man Young Lee),승기배(Ki Bae Seung),전승석(Seung Sok Chun),채장성(Jang Seong Chae),김종상(Jong Sang Kim),김재형(Jae Hyung Kim),홍순조(Soon Jo Hong),최규보(Kyu Bo Choi) 대한내과학회 1992 대한내과학회지 Vol.43 No.2

Background: Although the duration of the atrioventricular delay is known to affect ventricular diastolic filling time, the hemodynamic effects have been controversial. Several recent studies attempted to clarify the issue of optimal AV delay and have come to different conclusions. So we performed this study to evaluate the hemodynamic effects of varying A-V delays in A-V sequential pacing by echocardiography. Methods: 9 patients of this study had D,D.D. pace- makers because of complete atrioventricular block or sick sinus syndrome. The mean age of 5 male and 4 female patients was 49±22 years. Using the programming device, the pacing rate was set at 70/min, and at 5 different A-V delays (100, 125, 150, 175, 200, 250 ms), we measured the changes of various time intervals during systolic and diastolic phase by recording the M-mode echocardiogram of aortic and mitral valve, ECG, and phonocardiogram simultaneously. Results: In systolic phase, preejection periods were significantly shortened at A-V delay 200ms, 250 ms comparing to those of A-V delays below l75 ms. Left ventricular ejection times showed no statistically significant changes between various A-V delays. Systolic time intervals showed significant decrements at A-V delay 200 ms, 250 ms comparing to those of A-V delays below 175 ms. Changing the A-V delay from 100 ms to 250 ms, isovolumic contraction times were significantly pro- longed and isovolumic contraction time/preejection period ratios were significantly increased. And in diastolic phase, mitral valve opening times were significantly shortened at A-V delay 200 ms, 250 ms comparing to those of A-V delays below 175 ms. A spike-Mc intervals were significantly prolonged as changing the A-V delay from 100 ms to 250 ms. Conclusion: These data suggest that the change of A-V delay in D.D.D. pacemakers had variable effects on various time intervals of systolic and diastolic phase. Considering the close relationship between the systolic time interval and cardiac function, relatively long A-V delay such as 200 ms or 250 ms was thought to be more desirable in patients of this study. And measurement of systolic time interval by echocardiography could be used as an useful, noninvasive guideline for determining the optimal A-V delay in individual patient.

효율적 하부데크의 자유면 형성을 위한 수직방향 데크 단차 제안

정승원 ( Seung-won Jung ),이승중 ( Seung-joong Lee ),송진혁 ( Jin-hyuk Song ),김영호 ( Young-ho Kim ),송영석 ( Young-suk Song ),황남순 ( Nam-sun Hwang ) 대한화약발파공학회 2023 화약발파 Vol.41 No.4

This study, a vertical double-deck method using an electronic detonator was applied to increase excavation volume and reduce blast pollution. In the double deck method, there is a possibility that blasting efficiency may be reduced if bottom deck blasting is carried out without the free surface being completely formed after upper deck blasting. And for this reason, the blasting efficiency of the double deck method varies depending on the deck delay time. Therefore, in this study, we proposed four deck delay times applying 1 to 5 times the hole delay time. And blasting efficiency was evaluated according to fragmentation analysis. As a result of the fragmentation evaluation, the fragmentation of pattern 4 (deck delay time = hole delay time×5) was the best, but it was confirmed that fragmentation efficiency increased significantly from pattern 3 (deck delay time = hole delay time×3). Accordingly, it is analyzed that when blasting a vertical double deck, the deck delay time must be at least three times the hole delay time to obtain an efficient blasting effect.