• 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.

• Journal of the Korean Society of Costume
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• v.45
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• pp.71-84
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• 1999

This study was to identify the dimensions of consumer's purchasing motives and purchasing delay reasons toward casual hanbok. Other objective was to examine relationship between these variables and future purchasing intention. Th 22 purchasing motive questions and 19 purchasing delay reasons were selected through the result of self-questionnaire analysis. 302 purchaser and 297 consumers who delay for particular reasons in Pusan responsed to the second questionnaire of purchasing motives and purchasing delay reasons toward casual Hanbok. The results as follows: 1. For factor analysis 22 purchasing motive questions were subjected to the principle component analysis with orthogonal rotation after extraction of 6 major factors. Six dimensions are consciousness of nation goodness of design conformity with fashion charming apperance relaxation fo body and mind nation goodness of design conformity with fashion charming appearance relaxation of body and mind and pursuit of individuality. These factors explained 62.0% of total variables. 2. Consumer's purchasing motives such as consciousness of nation goodness of design charming appearance and relaxation of body and mind has predicting power to the re-purchasing intention of casual hanbok 3. For factor analysis 19 delay reason question were subjected to the principle component analysis with orthogonal rotation after extraction of 5 major factors. Five dimensions are non-fitness for occasion and body shape unsatisfaction with design unsatisfaction with price need of information search for better product and preference for traditional hangok. These factors explained 60.4% of total variables. 4. Delay reasons of unsatisfaction with design and price were positively related to the future purchasing intention. This delay reason is caused by forces external to the consumer and the consumer has engaged in information search. This result explained this type of consumer has the strong future purchasing intention.

• Journal of the Korea Institute of Building Construction
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• v.11 no.1
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• pp.9-17
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• 2011

Project delay is one of the most crucial impact factors in the construction process from a schedule and cost management perspective. This study focused on analyzing the causes of concrete frame work delay in the apartment construction project. According to the analysis of project cost composition, the direct cost of concrete works was highest in most samples. Actual delays of concrete works were analyzed for the six different construction components. Causes of delay were grouped into two categories; preconstruction and construction phases and these two groups were further divided into sub-groups. Analysis results revealed that the most significant delay was occurred in the 1st. floor concrete skeleton work. For each delay factor, implications of delay as well as suggestion(s) for reducing the possibility of schedule delay are provided.

• Journal of Positioning, Navigation, and Timing
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• v.2 no.1
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• pp.49-57
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• 2013

When pseudolite navigation system is applied to wide area, the tropospheric delay is the main error factor. In this study, we experimentally compared and analyzed the performance of the conventional pseudolite tropospheric delay models. The integration method using radiosonde meteorological data was suggested to derive the reference value for the comparison and analysis. Flight tests were carried out to analyze the performance of the tropospheric delay models according to the elevation angle and distance conditions between the user receiver and the pseudolite. As the results of this study, we provided the basis for the choice of tropospheric delay model appropriate to the relative location characteristics of the pseudolite and the user.

• Journal of the Korean Society of Combustion
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• v.18 no.4
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• pp.12-20
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• 2013

The ignition delay time is an important factor to understand the combustion characteristics of internal combustion engine. In this study, ignition delay times of cool and thermal flame were observed separately in homogeneous charge compression ignition(HCCI) engine. This study presents numerical investigation of ignition delay time of n-heptane and alcohol(ethanol and n-butanol) binary fuel. The $O_2$ concentration in the mixture was set 9-10% to simulate high exhaust gas recirculation(EGR) rate condition. The numerical study on the ignition delay time was performed using CHEMKIN codes with various blending ratios and EGR rates. The results revealed that the ignition delay time increased with increasing the alcohol fraction in the mixture due to a decrease of oxidation of n-heptane at the low temperature. From the numerical analysis, ethanol needed more radical and higher temperature than n-butanol for oxidation. In addition, thermal ignition delay time is sharply increasing with decreasing $O_2$ fraction, but cool flame ignition delay time changes negligibly for both binary fuels. Also, in high temperature regime, the ignition delay time showed similar tendency with both blends regardless of blending ratio and EGR rate.

• 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 Optical Society of Korea
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• v.17 no.5
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• pp.415-422
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• 2013

White-light phase-shifting interferometry (WLPSI) is widely recognized as a standard method to measure shapes with high resolution over a long distance. In practical applications, WLPSI, however, is associated with some degree of ambiguity of its phase, which occurs due to a phase delay, which is the offset between the phase of the fringes and the fringe envelope peak position. In this paper, a new algorithm is proposed for the determination of a fringe order suitable for samples in which the phase delay mainly occurs due to noise, diffraction and a steep angle. The concepts of the decouple factor and the connectivity are introduced and a method for calculating the decouple factor and the connectivity is developed. With the phase-unwrapping procedure which considers these values, it is demonstrated that our algorithm determines the correct fringe order. To verify the performance of the algorithm, a simulation was performed with the virtual step height under noise. Some specimens such as step height standard and a column spacer with a steep angle are also measured with a Mirau interference microscope, after which the algorithm is shown to be effective and robust.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.5
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• pp.48-58
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• 1998

In this paper, we proposed a new algorithm using characteristics of th ereconstructed phase trajectory by topological mapping developed for a real-tiem detection of the QRS complexes of ECG signals. Using fill-factor algorithm and mutual information algorithm which are in genral used to find out the chaotic characteristics of sampled signals, we inferred the proper mapping parameter, time delay, in ECG signals and investigated QRS detection rates with varying time delay in QRS complex detection. And we compared experimental time dealy with the theoretical one. As a result, it shows that the experimental time dealy which is proper in topological mapping from ECG signals is 20ms and theoretical time delays of fill-factor algorithm and mutual information algorithm are 20.+-.0.76ms and 28.+-.3.51ms, respectively. From these results, we could easily infer that the fill-factor algorithm in topological mapping from one-dimensional sampled ECG signals to two-dimensional vectors, is a useful algorithm for the detemination of the proper ECG signals to two-dimensional vectors, is a useful algorithm for the detemination of the proper time delay. Also with the proposed algorithm which is very simple and robust to low-frequency noise as like baseline wandering, we could detect QRS complex in real-time by simplifying preprocessing stages. For the evaluation, we implemented the proposed algorithm in C-language and applied the MIT/BIH arrhythmia database of 48 patients. The proposed algorithm provides a good performance, a 99.58% detection rate.

• International Journal of Human Ecology
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• v.13 no.2
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• pp.1-13
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• 2012

This study examined the effects of academic self-concept (internal factor) and maternal parenting behaviors (external factor) on academic delay of gratification (ADOG). Additionally, models predicting ADOG were compared between Korean and Malaysian children. The participants of this study were 100 Korean third graders and their mothers, and 100 Malaysian third graders and their mothers. The children completed the modified versions of the Academic Delay of Gratification Scale for Children, and Academic Self-Concept Questionnaire. The mothers completed the Parenting Attitude Test. Pearson's correlation tests, independent t-tests, and multiple regression analyses were conducted to test the research hypotheses. The results showed that Korean children reported higher ADOG and academic self-concept scores than that of Malaysian children. Moreover, academic self-concept was found to have a significant positive effect on ADOG among both Korean and Malaysian children. There was no significant gender difference in ADOG for both Korean and Malaysian children. However, the effects of maternal parenting behaviors on ADOG were only detected among the Malaysian children, particularly on Achievement Press. That is, only for the Malaysian children, maternal pressure about academic achievement was found to have a significant positive effect on ADOG. In conclusion, only academic self-concept was found to be a significant predictor explaining the variance in ADOG among Korean children. On the other hand, academic self-concept and maternal parenting behaviors were shown as significant predictors explaining the variance in ADOG among Malaysian children.

• Journal of Korea Multimedia Society
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• v.24 no.12
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• pp.1632-1640
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• 2021

In order to improve target tracking performance of the conventional electro-optical tracking system (EOTS) in the high speed and high maneuvering vehicle, an EOTS navigation algorithm is proposed, in which an inertial measurement unit(IMU) is included and navigation results of the vehicle are used. The proposed algorithm integrates vehicle's navigation results and the IMU and the time-delay and the scale factor errors are augmented into the integrated Kalman filter. In order to evaluate the proposed navigation algorithm, a land vehicle navigation experiments were performed a navigation grade navigation system, TALIN4000 and a tactical grade IMU, LN-200 and a equipment for roll motion were loaded on the land vehicle. The performance evaluation results show that the proposed algorithm effecting works in high maneuvering environment and for the time-delay.