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.

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.

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

N/A 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.

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

Liver dynamic CT 검사 시 족부 (arteries of lower extremity) I.V Line 으로 조영제 주입 후 bolus tracker 의 scan delay time 설정 변화에 따른 환자 피폭선량 감소를 위한 비교연구

전찬일(Chan Il Chun),김기원(Ki Won Kim),박계연(Kye Yeon Park),권민우(Min Woo Kwon) 대한CT영상기술학회 2015 대한CT영상기술학회지 Vol.17 No.1

목적 : CT 검사 시 bolus tracking 기법을 이용한 검사 중 상지에 IV(intravenous) 루트를 확보 하지 못하거나 혈관 확보가 어려운 환자의 경우 부득이하게 족부에 IV line 을 확보 한다. 이런 경우, 상지에 IV line 을 확보한 경우 보다 족부에 IV line을 확보했을 때 bolus tracking 검사 시, 조영제 주입후의 traker의 threshold 값과 설정된 ROI 값의 H.U 까지 도달하는 시간이 차이가 있음을 인지하고, locate scan delay time 설정에 따른 환자 피폭선량의 차가 어느 정도이며, 설정에 따른 선량감소가 어느 정도인지 비교 분석하여 Bolus tracking 기법 검사 시 적절한 tracker scan delay time 설정으로 불필요한 환자의 방사선 피폭을 줄이는데 그 목적이 있다. 대상 및 방법 : 대상 및 방법은 2014년 1월 1일부터 2014년 8월 1일까지 약 7개월에 걸쳐서 Liver dynamic CT 검사를 한 전체 성인 남녀 환자를 대상으로 하였으며, 전체 2100여건의 검사 수 중 수집된 검사건수는 SIEMENS sensation16 장비가 35건, TOSIBA AQILION ONE에서 13건 수집되었다. 방법은 상지부위에 IV injecting root 가 확보 되지 않아 족부에 IV root가 확보된 환자를 남녀 구분 없이 대상으로 하였다. Liver Dynamic CT 검사를 한 성인 남녀 환자를 대상으로 결과 값인 dose information 데이터에서 기록된 조영제 주입 후, tracking시 합산된 CTDI, DLP 데이터 값을 수집하여 비교 분석하였다. 분석에 사용된 프로그램은 SPSS statistics 18.을 사용하였으며 최대값, 최소값, 평균값을 도출하였다. 결과 : 수집된 환자 전체 48명중 남성(34명), 여성(14)이었고, 남성 환자의 경우 평균연령 62세, 여성 환자 경우 평균연령 67세 였다. sensation 16 장비에서 수집 자료를 분석하였을 때 조영제 주입 후 현재 설정 값인, delay time 12sec threshold +100HU를 도달하기까지 걸리는 시간은 최소 +6.25초, 최대 +17.5초가 걸렸으며, AQILION ONE 320의 경우는 설정된 delay time 10sec threshold +140HU 도달 시간은 최소 +8, 최대 +20sec 가 소요되었다. 자료 분석 과정에서, 상지와 하지 두 부위를 모두 각각 다르게 조영제를 투입하고 liver dynamic CT 검사를 한 환자의 경우, 피폭선량은 하지로 주입했을 시 DLP값이 최소 2배에서 최대 6배까지 차이가 남을 알 수 있었다. 또한 scan start time은 자료 분석 결과 최소 7초에서 최대 14초까지 차이가 남을 알 수 있었다. 또 두 장비에서 수집된 자료에서 평균 scan start time 이 22sec 정도로 분석되었는데, 실제 이 결과를 토대로 검사 시, 설정된 값을 delay12sec + 10sec한 22초로 검사한 경우 환자가 받는 피폭선량을 최소 50%에서 최대 80%까지 줄일 수 있다는 걸 알 수 있었다. 결론 : 하지에 IV루트를 확보 후 검사한 환자의 경우에는 최소 8초에서 10초 정도 Delay time 을 추가로 재설정한다면 환자가 받는 불필요한 피폭을 최소 50%에서 최대 80%까지 줄일 수 있음을 알 수 있었다. Purpose : If the patients didn’t have an IV line to the upper extremity(Antecubital vein) or the patinet’s vascular access was difficult, patients must have IV line on foot(Dosalis pedis vein). In this case, it was recongnized that there was a difference in time between the threshold value of tracker after the contrast injection and the HU of set ROI value, and were differences in patient exposure dose according to the locate scan delay time setting. So, compared to how much the dose reduced according to the set, the purpose of this study was to reduce unnecessary exposure dose of the patient by appropriate tracker scan delay time setting. Materials and Methods : Until August from January, 2014, we analyzed the entire adult male and female. Of total number of 2100 tests, 35 tests was collected at SIEMENS Sensation 16, and 13 tests was collected at TOSIBHA AQUILION ONE. We collected and analyzed the summed CTDI, DLP data value when tracking after the contrast injection. We used quantitative analysis programs (SPSS statistics 18 programs) and the maximum values, the minimum values and the average values were derived. Results : Of total number of 48 patients, 34 patients were males and 14 patinets were females. For male patients, the average age is 62 years old. For female patients, the average age is 67 years old. Analysing of the results, in Sensation16, after the contrast injection, The time it takes go beyond 100 HU values is minimum 6.25 seconds and maximum 17.5 seconds. In AQILLION ONE, The time it takes go beyond 140 HU values is minimum 8 seconds and maximum 20 seconds. Compared to the tests in upper extremity IV line and on foot IV line, we found that DLP values remain a difference up to 6 times more than doubled and the scan starting time remain a dfference up to 7-14sec. Also, we analyzed that the average scan starting time is 22sec, when the actual test based on this result, we know that the exposure dose of the patient can be reduced by from minimum 50% to maximum 80%. Conclusion : After we have IV line on foot(Dosalis pedis vein), if we reset delay time in range of 8 in minimum to 10 seconds, we can reduce unnecessary exposure from minimum 50% to maximum 80%.

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

본 연구에서는 굴착 물량 증대와 발파공해 저감을 위해서 전자뇌관을 이용한 수직방향 더블 데크 공법을 적용하였다. 더블 데크 공법은 상부 데크 발파 후 자유면이 완전히 형성되지 않은 상태에서 하부 데크 발파가 진행되면 발파 효율이 감소할 가능성이 있다. 이와 같은 이유로 더블 데크 공법은 데크 단차에 따라서 발파 효율이 달라진다. 따라서 본 연구에서는 홀 단차의 1~5배를 적용한 4가지 데크 단차를 제안하였고, 발파 후 파쇄도 분석을 통해 발파 효율을 평가하였다. 파쇄도 평가 결과 패턴 4(데크 단차=홀 단차×5)의 파쇄도가 가장 좋았으며, 패턴 3(데크 단차=홀 단차×3) 이상에서 파쇄효율이 큰 폭으로 증가하는 것을 확인할 수 있었다. 이에 따라 수직방향 더블 데크 발파 시 데크 단차는 최소 홀 단차의 3배 이상이 되어야 효율적인 발파 효과를 얻을 수 있다고 분석되었다. 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.