• Journal of the Society of Disaster Information
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• v.11 no.1
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• pp.107-119
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• 2015

The flood or inundation that occur in high-density city can paralyze urban functions and cause a lot of casualties. In this study, to minimize the damage, the disaster mitigating urban design techniques for the divided basin as disaster occurring point, disaster vulnerable site, urban responding region are applied. First of all, to do this, it is necessary to verify the effectiveness of urban design techniques by simulating them. Therefore, in this paper, the applicability of urban runoff models used in domestic disaster reduction study was investigated to analyze the outflow decrease efficiency of urban design techniques. As the reviewing results, the limitations of the lumped models such as FFC2Q and XP-SWMM are presented.

• Communications for Statistical Applications and Methods
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• v.5 no.1
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• pp.205-215
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• 1998

정규분포에 관한 검정에 있어서 P-P 플롯과 Q-Q 플롯의 가시적인 변동을 이용한 통계량을 제시하고 이 통계량들과 Shapiro-Wilk의 W 통계량과의 비교를 정확도(accuracy)의 측면을 고려하여 실시하였다. 또한, 의학이나 임상에서 척도의 우수성을 검정하기 위해 많이 사용하는 Receiver Operating Characteristic (ROC) 분석 기법을 이용하여 제시된 통계량들에 관한 Power와 Accuracy는 물론 Best Cut-Off 측면에서의 효율성을 검정하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.11B
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• pp.1269-1276
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• 2011

In the Proxy Mobile IPv6 (PMIPv6), the data transmission performance may be degraded when the two communicating hosts are located within the same mobile domain, since all the data packet shall be delivered by way of Local Mobility Anchor (LMA). In this paper we propose an extensional scheme of PMIPv6 using binding query. In the proposed Query-based PMIPv6 (Q-PMIPv6) scheme, the Mobile Access Gateway (NAG) of Correspondent Node (CN) sends a binding query to LMA to obtain the Proxy Care-of-Address of Mobile Node (MN). Since then, CN and MN can communicate with each other by using an optimized data path. For comparison, we performed the numerical analysis and the ns-2 simulations for the proposed Q-PMIPv6 scheme and the existing PMIPv6 and PMIPv6 Localized Routing (PMIPv6-LR). From the results, we can see that the proposed scheme outperforms the existing PMIPv6 and PMIPv6-LR schemes in terms of the signaling control and data delivery costs.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.5
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• pp.1133-1138
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• 2010

In the anti-collision scheme proposed by EPCglobal Class-1 Gen-2 standard, the frame size for a query round is determined by Q-algorithm. In the Q-algorithm, the reader calculates a frame size without estimating the number of tags in it's identification range. It uses only the slot status. Therefore, Q-algorithm has advantage that the reader's algorithm is simpler than other algorithms. However, it cannot allocate an optimized frame size because it does not consider the number of tags. Also, the conventional Q-algorithm does not define an optimized parameter value C for adjusting the frame size. In this paper, we propose a modified Q-algorithm and evaluate the performance with computer simulations. The proposed Q-algorithm estimates the number of tags at every query round, and determines the parameter value C based on the estimated number of tags.

• Asia Marketing Journal
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• v.1 no.3
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• pp.120-140
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• 1999

Q 방법은 인간의 태도와 행동을 연구하기 위해 철학적, 심리학적, 통계적, 그리고 심리측정과 관련된 개념을 통합한 방법론으로서 인간의 주관성을 정량적으로 분석할 수 있는 특수한 통계기법이다. 소비자의 인식, 가치, 태도, 신념과 같은 개념을 객관적으로 연구할 수 있는 방법으로서 가설 생성을 위한 탐색적 연구와 이론의 검증과 같은 확인적 연구에서도 적용될 수 있다. 많은 수의 표본을 대상으로 한 횡단적 R 방법에 비하여 개인이나 소집단에 대한 깊이 있는 탐구가 가능하다는 점에서 소비자 행동 연구에 유용성이 매우 높다. 개인의 주관성을 바탕으로 한 소비자 개인의 특성과 차별성을 이해하는 것이 마케팅 분야의 핵심을 이루고 있음에도 불구하고 그 동안 소비자의 주관성에 대한 깊이 있는 접근이 이루어지지 못하였다. 1935년에 심리학 분야에서 개발된 Q방법은 이를 분석할 수 있는 컴퓨터 패키지의 보급과 더불어 사회과학 전반에 걸쳐 그 활용이 확산되어 가고 있다. 이에 Q 방법의 과학철학적 특성과, 현재 널리 이용되고 있는 변수 중심의 R 방법과의 차이, 그리고 컴퓨터 분석을 포함한 구체적인 Q 분석방법 및 관리적 활용상의 문제점에 대해 논의하였다

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.3
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• pp.224-239
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• 2013

An exact performance analysis of an ML detector for a 2-dimensional rotation-transform aided QPSK system operating over an impulsive noise environment is presented using Rieman integrals of a two-dimensional Gaussian Q-function over Voronoi cells. A set of interesting features of the Voronoi cells is also characterised systematically. An optimum rotation angle yielding the minimum BER is also studied. The differences between the proposed exact method and the previous approximate analysis method are investigated in terms of the corresponding BERs and the derived optimum angles.

• Journal of Food Hygiene and Safety
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• v.33 no.1
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• pp.23-30
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• 2018

The purpose of this research was to introduce network analysis method for analyzing pesticide residues in incongruity commercial agricultural commodities. Based on the "results in pesticide residues on incongruity commercial agricultural commodities" on "Guidelines for food safety management 2017", we used centrality analysis for pesticide residues via degree, closeness and betweenness centrality measurement. In case of degree centrality result, chlorpyrifos and diazinon were the most highly "connected node" in pesticide network. For the closeness centrality result, the most pesticides showed the similar closeness trend except for 19 species of pesticides. Fludioxonil and chlorpyrifos are recognized as the "bridge" of pesticides network with their high betweenness centrality. The results of network analysis show the "relation" data, which could not represent through out the conventional statistical analysis, among the pesticide residues. We hope that the network analysis method will be appropriate and precise tool for analyzing pesticide residues via elaboration and optimization.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.6
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• pp.39-47
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• 2012

As a scheme to efficiently reduce the effects of multipath fading in next generation wireless communication systems, cooperative communication systems have recently come into the spotlight. Since these cooperative communication systems use cooperative relays with diverse fading coefficients to transmit information, having all relays participate in cooperative communication may result in unnecessary waste of resources, and thus relay selection schemes are required to efficiently use wireless resources. In this paper, we propose an efficient relay selection scheme through self-learning in cooperative wireless networks using Q-learning algorithm. In this scheme, we define states, actions and two rewards to achieve good SER (Symbol Error Rate) performance, while selecting a small number of cooperative relays. When these parameters are well-defined, we can obtain good performance. For demonstrating the superiority of the proposed Q-learning, We compared the proposed scheme with Q-learning and a relay selection scheme with a mathematical analysis. The simulation results show that, compared to a scheme that obtains optimum relays through a mathematical analysis, the proposed scheme uses resources efficiently by using smaller numbers of relays with comparable SER performance. According to these simulation results, the proposed scheme can be considered as a good attempt for future wireless communication.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.9
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• pp.1928-1934
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• 2009

This paper proposes a power management scheme for sensor nodes in wireless sensor networks based on sensor node operating system supporting the sensor transparency, which can turn off the sensors when the MCU is in sleep mode. We classify the sensors in two types, that is, event sensors and polling sensors, to be able to decide whether the sensor is a type of sensors whose power supply can be turned off or not, and we design a new scheduler to support recognition of those different types of sensors. Implementing and evaluation of the scheduler and the power manager supporting sensor transparency are shown based on Nano-Q+.

• Korean Journal of Environment and Ecology
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• v.10 no.2
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• pp.283-296
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• 1997

To investigate the plant community structure in valley and suggest the management of Mational Park, fifty plots were set up and surveyed in Jujeongol Valley, Soraksan National Park. The classification by TWINSPAN and DCA ordination technique were applied to the study area in order to classify them into several groups based on woody plants. The dividing groups were Quercus mpnngolica - Q. variabilis - Pinus densiflora community, P. densiflora community, Carpinus laxiflora community, Q. serrata community. The ecological trends of tree species by DCA ordination technique and DBH class distribution analysis was like that Q. mongolica - Q. variabilis - P. densiflora community and P. densiflora community seems to be trended from P. densiflora community to Q. mongolica community. Q. serrata community seems to be trended from Q. serrata community to C. laxiflora community and C. laxiflora will be maintaimed stable state.