• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.1310-1312
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• 2007

Throughput improvement problem in wireless mesh network can be alleviated by equipped mesh router with multiple radios tuned into orthogonal channels. However, some links on the same channel also can be activated concurrently if the Signal-to-Noise and Interference Ratio (SNIR) at their receiver endpoints is not lower than the threshold. We propose a greedy algorithm to investigate the problem of how to schedule a set of feasible transmission under physical interference model by using the spatial time-division multiple-access (STDMA) scheme. We also consider the fairness in scheduling to prevent some border nodes from starvation. We evaluate our algorithms through extensive simulation and the results show that our algorithms can achieve better aggregate throughput and fairness performance than 802.11 standard.

• Korean Journal of Child Studies
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• v.13 no.2
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• pp.251-272
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• 1992

The purpose of this study is to investigate the relationships among the beliefs of parents and children, children's cognitive and emotional behavior based on cognitive and interreactionary approach models. The Subjects were 138 children (68 eight-year-olds and 70 eleven-year-olds) and their parents. Instruments used in this study were the modified Family Belief Interview Schedule(Alessandri & Wozniak, 1987), the Standard Achievement Test, and Harter's Perceived Competence Scale. Data analysis was by Pearson's r product moment correlation, two-way ANOVA, Fisher-Z test and Student-Newman-Keuls post-hoc test. The major findings are as follows: (1) The beliefs of parents and children has a significant influence children's perception of competence. (2) The congruence of parents' and children's beliefs was hightest in "assumed similarity". (3) Mother's positive view of their children and congruence of mother's and father's beliefs were correlated with children's academic achievement. Parents' positive beliefs and congruence of beliefs were also correlated with children's self-perception of competence.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.156.4-156
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• 2001

The uncertainties of an atmospheric re-entry flight with respect to stability and controllability are aerodynamic error, measurement error of the angle of attack, variation of dynamic pressure, wind, and trim position of the control surfaces, etc. During hypersonic flight, a future angle of attack is biased from a nominal schedule. In order words, because the angle of attack is estimated from the navigation data, estimation error occurs due to wind, atmospheric density variation, etc. Error models used in this study, include a standard deviation of +-3 sigma, and are the normal distribution of statistics. This paper shows the appraisement of tracking performance onto the reference trajectory, satisfaction of the initial condition of TAEM about the re-entry system.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2297-2302
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• 2010

The status and effectiveness of Bi-modal Tram is analyzed through the comparison of the transport effectiveness and operation cost between the public transportation systems (bus, light rail transit) considering the vehicle and operation characteristic of new transit system Bi-modal Tram. The standard operation schedule is established in consideration of the vehicle specification and operation characteristic of main public transportation modes, and then the annual average operation cost is estimated depending on the volume, speed, analysis length for respective public transportation mode. Through analyzing the operation cost and distribution characteristic of public transportation modes depending on the transport volume and travel speed, the operational efficiency suitable for the city is derived. It is concluded that the operational efficiency of Bi-modal Tram is superior to that of the bus and light rail transit on the aspect of travel volume and operation speed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.921-926
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• 2000

Recently, in construction field, large construction equipment are used to reduce the construction schedule and labor cost. Therefore, construction vibration has caused much annoyance and that induced from operating of large construction equipment, has become a major problem for a number of dwellers in nearby construction field and it has become a very serious issue in our living environment. In this point, this study attempts to survey on the characteristics of piling vibration by oil pressure method in construction field. And this study intends to get the basic data to establish a standard about construction vibration.

• Journal of The Korean Digital Architecture Interior Association
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• v.6 no.1
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• pp.1-4
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• 2006

This research studied necessary digital Interior Design education and certification formality for Dept. of Interior Design students' percentage of employment raising and competitive power elevation of industry by the support of 2005 junior college finance support business from the Ministry of Education & Human Resources Development. Contents of this research is built from joint research by vender of software, which has the highest distribution and preference rate of digital Interior Design related software in industry, and The Korea Digital Architecture and Interior Association, and Daeduk college. The necessary certification standard and course-ware for employment of graduates were developed. There are descriptions for students' needs on digital Interior Design related practical application ability that can receive authentication, And made out education schedule as well as contents so that execution of authentication and education may be possible.

• Journal of Communications and Networks
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• v.14 no.3
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• pp.310-318
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• 2012

Detecting intrusion attacks accurately and rapidly in wireless networks is one of the most challenging security problems. Intrusion attacks of various types can be detected by the change in traffic flow that they induce. Wireless industrial networks based on the wireless networks for industrial automation-process automation (WIA-PA) standard use a superframe to schedule network communications. We propose an intrusion detection system for WIA-PA networks. After modeling and analyzing traffic flow data by time-sequence techniques, we propose a data traffic prediction model based on autoregressive moving average (ARMA) using the time series data. The model can quickly and precisely predict network traffic. We initialized the model with data traffic measurements taken by a 16-channel analyzer. Test results show that our scheme can effectively detect intrusion attacks, improve the overall network performance, and prolong the network lifetime.

• Korean Journal of Construction Engineering and Management
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• v.8 no.6
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• pp.235-245
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• 2007

This research study presents the development and application of an Elitist Genetic Algorithm (Elitist GA) for solving the resource-constrained project scheduling problem, which is one of the most challenging problems in construction engineering. Main features of the developed algorithm are that the elitist roulette selection operator is developed to preserve the best individual solution for the next generation so as to obtain the improved solution, and that parallel schedule generation scheme is used to generate a feasible solution to the problem. The experimental results on standard problem sets indicate that the proposed algorithm not only produces reasonably good solutions to the problems over the heuristic method and other GA, but also can find the optimal and/or near optimal solutions for the large-sized problems with multiple resources within a reasonable amount of time that will be applicable to the construction industry. This paper will help researchers and/or practitioners in the construction project scheduling software area with alternative means to find the optimal schedules by utilizing the advantages of the Elitist GA.

• Plant Journal
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• v.6 no.2
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• pp.56-61
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• 2010

In this paper, an integrated management software is developed to promote the business competitive power. The interoperability among the software accounts for an ever growing performance of petrochemical plant project. If the interoperability is built up, company has taken advantages of quality, schedule, cost, and safety by active communication. The advantage of an integrated management software is examined in three aspects. In efficiency aspect, It takes advantage of the saving about the various information and the standard of project performance procedure. In quality, the integration gave aid to a quality improvement through team collaboration and data management within project life cycle. In cost, poor communications between systems waste 30% of project costs. If information could be inputted once and used by all, reductions in delivery time up to 40% were possible. Therefore, 10% savings of engineering cost was also possible.

• Journal of the Korean Geophysical Society
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• v.4 no.3
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• pp.163-173
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• 2001

This paper deals with scheduling problems which are the most important subtask in High-Level Synthesis. Especially, we have concentrated our attentions on the data-path scheduling which can get the structural informaion trom the behavioral algorithm as a first step in synthesis procedure. Suggest Forward scheduling methode is executed the ASAP and ALAP scheduling to use the fifth - order elliptic wave filter of a standard benchmark moedl, and then it is drawing up T.N matrix table by the number resource and control-step, using the table extract of the simple than down-limit value of the control-step for the number of given resource th use this table. All of existing list scheduling techniques determine the priority function first, and then do the operation scheduling, But, the suggested forward scheduling technique does the schedule first, and determines the priority functions if needed in scheduling process.