• Journal of Internet Computing and Services
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• v.8 no.2
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• pp.33-41
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• 2007

With the development of the multicast technology, the realtime strategy among the group applications using the multicast routing is getting more important. An essential factor of these real-time application is to optimize the Delay- and delay Variation-Bounded Multicast Tree(DVBMT) problem. This problem is to satisfy the minimum delay variation and the end-to-end delay within an upper bound. The DVBMT problem is known as NP-complete problem. The representative algorithms for the problem are DVMA, DDVCA, and so on. In this paper, we show that the proposed algorithm outperforms any other algorithm. The efficiency of our algorithm is verified through the prerformance evaluation and the enhancement is up to about 9% to 29% in terms of the multicast delay variation. The time complexity of our algorithm is $O(mn^2)$M.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.2
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• pp.336-341
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• 2010

The burning interruption between the initiator and the delay column in a Zr-Ni K1 delay system used for a K510 fuze occurs with long-time storage. About 10 % failure probability of 15-years stored delay systems shows the failure mode in open literature. This paper shows storage lifetime improvement results for the delay system through changing the single-base delay column into double-base ones and controlling the manufacturing processes especially the initial inclusion of humidity. The double-base delay columns was implemented by inserting one delay column of fast burning rates between the initiator and the previous delay column of slow burning rates. Accelerated aging tests of the delay systems with double-base columns, and then the firing tests were performed to evaluate the improved lifetime. The double-base delay columns shows improved storage lifetime of the delay system through preventing the failure mode.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.5B
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• pp.365-369
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• 2012

It is very important to control synchronization by inter-network delay compensation in high speed synchronous optcial transmission network systems. In this study we designed a delay measurement system based on OTDR using Rayleigh backscatterer in order to compensate for time delay due to the length of optical fiber line. We observed waveform variations on both averaging time and peak power of laser pulse. Finally, we executed experimental demonstration on its accuracy and test repeatability by comparison to the methods practically used in the industry. Experimental results show maximum error of 0.06usec and standard deviation of 0.021usec, which means it's possibly applied to delay control system for mobile repeaters and stations.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.3
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• pp.286-292
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• 2010

In this paper, we investigate the relationship between the performance of telerobotic systems and the two independent time-delay on different modality, which are haptic and video. Especially, we try to find some performance improvement when the amount of delay of haptic and video is synchronized. Experiments were conducted with 10 subjects by scanning the amount of video and haptic delay independently. It is rather interesting to note that the teleoperation performance was not that sensitive to video delay, and the synchronized video and haptic delay doesn't show better performance than the case when haptic delay is lower than video delay.

• Journal of IKEEE
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• v.3 no.1 s.4
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• pp.50-56
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• 1999

This paper presents a new technique for generating precise clock delays. The technique can obtain finer timing resolution less than the gate delay of the delay chain by locking in multiple clock period. Using this technique, a 250ps of timing resolution could be achieved from a 750ps delay of the single delay stage in a DLL(Delay Locked Loop) structure. The delay chain of the proposed circuit is locked on three times of the clock period and a finer delay resolution than the absolute gate delay is achieved and verified through the simulation.

• Journal of Construction Engineering and Project Management
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• v.2 no.3
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• pp.17-29
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• 2012

Delays are one of the biggest problems facing by the construction industry and they have significant financial and social impact in construction projects. The paper presents a framework of Delay Analysis System (DAS) with the aim of analysing the impact of delay factors in Libyan construction projects. The system has designed by integrating the possible delay factors, critical activities of a project using@risk simulator. A case study of building project was demonstrated to identify the impact of delays and the sensitivity of delay factor. The case study result showed that the project might be delayed by 97 to 103 days in comparison to the planned duration. The developed DAS is a tool for analysing and identify the impacts of delay factors and assist to construction manager to take necessary measure in reducing the delay impact. The paper provides a methodology for analysing the possible delay impact in a construction project and informing to construction manager in advance of the possible delay factors.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.161-165
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• 2015

The delay in construction is the challenge often faced in the course of executing construction projects. To the government projects, the delays become very serious. This problem directly affects the lives, social welfare of the people, and the other negative social impacts. However, the government projects have not been much interest. The questionnaire surveys in Vietnam were conducted to determine the causes of the delay and to find solutions for dealing with the delay. The average index was used to rank the delay factors and the solutions. This study identified the 5 most highly ranked delay factors and the 8 best solutions from a list of 31 delay factors and 19 solutions for the delay. The five most highly ranked delay factors were: information delays and lack of information exchange between the parties; incompetent owner; incompetent supervision consultant; incompetent contractor; and difficulties in financing project by owner. The findings of the study can help the parties involved the government construction projects and practitioners to give appropriate strategies for countering the delay in their projects.

• International Journal of Human Ecology
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• v.1 no.1
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• pp.59-77
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• 2000

The purpose of this study was to extend our understanding of the developmental antecedents of delay of gratification in infancy. The first goal was to examine direct effects of one feature of an infants’ temperament and of positive and negative parenting assumed at age one on children’s delay of gratification six months later. The second goal of the study was to test the interactive effect of early infant temperament and parenting on children’s delay of gratification. It was hypothesized that 1) less negative infants at 12 months would delay gratification longer six months later, 2) children of parents who provided more positive and sensitive feedback would delay gratification longer than children with parents who were more negative and less sensitive, and 3) there would be differential prediction of parenting for children who scored high and low in negative emotionality as infants. Toward this end, 81 infants were observed interacting at one year of age with their mothers and fathers during laboratory assessments to obtain measures of parenting and infant negative emotionality. At 18 months of age, the child’s capacity to delay touching attractive objects was measured. The main effects of infant negative emotionality and of mothering on children’s delay of gratification were not detected at standard levels of significance. Differential effects of parenting on children’s delay of gratification for infants with low or high negative emotionality, too, were not detected. However, the anticipated effect of fathering on delay of gratification was found in some analyses, indicating that the more positive fathering children received, the longer they could delay gratification in the laboratory six months later.

• Health Policy and Management
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• v.13 no.4
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• pp.115-130
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• 2003

Reperfusion delay in patients with acute myocardial infarction leads to increased morbidity and mortality. We sought to measure the rates of reperfusion delay and to identify factors associated with reperfusion delay after arrival to hospitals. We included 360 patients who had acute myocardial infarction with ST-elevation or left bundle branch block on electrocardiogram and received reperfusion therapy from the three participating academic medical centers from 1997 to 2000. Through retrospective chart review, we collected data about time to reperfusion therapy, patient and hospital factors potentially associated with reperfusion delay. Factors independently associated with reperfusion delay were determined by logistic regression analysis. Median door­to­needle time was 60.0 minutes, and median door­to­balloon time was 102.5 minutes. According to recommendation of the American College of Cardiology/American Heart Association Guidelines, 226 out of 264(85.6％) of thrombolytic patients and 43 out of 96(44.8％) percutaneous transluminal coronary angioplasty(PTCA) patients experienced reperfusion delay. The significant factors associated with delay were type of reperfusion therapy, patient factors including hypertension and delayed symptom onset to presentation(>4 hours), and hospital factors including nocturnal presentation(6pm∼8am), weekend, and an individual hospital. A significant proportion of patients experienced reperfusion delay. The identified predictors of reperfusion delay may help design a hospital system to reduce the delay in reperfusion therapy

• Journal of Korean Society of Transportation
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• v.10 no.1
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• pp.41-54
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• 1992

The purpose of this thesis is to construct a model to estimate the delay that vehicles arriving randomly will be experienced at an isolated singalized intersection. To do this the following objectives are set in this study: (i) An what distance a random arrival pattern occurs after a platoon of vehicles are dis-charged from the stop line; (ii) A model which estimates the average delay per through-vehicle with respect to the de-gree of saturation; and (iii) The relation between the stepped delay and average approach delay per vehicle. The following are the findings of this study: (i) A random arrival pattern on the first second and third lanes occur 300,400 and 300m downstream from stop line rdspectively. A random arrival pattern on lane group occurs 500m downstream from the stop line ; (ii) A model for the estimation of approach delay has been developed in such a way that up to x=0.7 the delay increases linearly and beyond 0.7 the delay increases rapidly in a form of second order polynomial due to high degree of saturation : and (iii) Approach delay equals approximately 1.21 times of stopped delay.