• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.1
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• pp.1-6
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• 2012

In this paper, we present an obstacle avoidance control algorithm for mobile robots based on SFLC (single-input fuzzy logic controller) with an efficient fuzzy logic look-up table to replace the traditional complicated operation. This method achieves better performance than traditional methods in terms of efficiency. The output of a SFLC leads the robot to the target automatically although many obstacles on the path. Our experiments show that the robot has good performance in the view of path tracking and other efficiency.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.9
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• pp.1718-1726
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• 2006

In this paper, we proposed a fuzzy controller and algorithm for efficiently obstacle avoidance in unknown space. The ultrasonic sensor is used for position and distance recognition of obstacle, and fuzzy controller is used for left and right wheels angular velocity control. The fuzzification is used singleton method and the control rule is each wheel forty-nine. The fuzzy inference is used simplified Mamdani's reasoning and defuzzification is used SCOG(Simplified Center Of Gravity). The computer simulation based on mobile robot modelling was performed for the capacity of fuzzy controller and the really applicable possibility revaluation of the proposed avoidance algorithm and fuzzy controller. As a result, mobile robot was exactly reached in target and it avoided obstacle efficiently.

• Journal of IKEEE
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• v.22 no.2
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• pp.440-445
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• 2018

The work presented in this paper deals with a navigation problem for a multiple mobile robots in unknown dynamic environments. The environments are completely unknown to the robots; thus, proximity sensors installed on the robots' bodies must be used to detect information about the surroundings. In order to guide the robots along collision-free paths to reach their goal positions, a navigation method based on a combination of primary strategies has been developed. Most of these strategies are achieved by means of fuzzy logic controllers, and are uniformly applied in every robot. In order to improve the performance of the proposed fuzzy logic, the genetic algorithms were used to evolve the membership functions and rules set of the fuzzy controller. The simulation experiments verified that the proposed method effectively addresses the navigation problem.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.3
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• pp.34-41
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• 2014

Through applying hostile radar signals that use stagger PRI to PRI transform in real time, we can analyze stagger PRI and calculate the future TOA for active cancellation by using measured TOA and estimated PRI. We shows the effect of the errors that are contained in PRI and measured TOA. Then, it will suggest the technique to improve the accuracy of estimated PRI and the TOA averaging method for reducing the effect of measured TOA error. Finally, we will show that accuracy of estimated future TOA that is calculated by proposed scheme is higher than that of future TOA that is simply calculated with TDOA and newest TOA through comparing RMSE performance.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.1
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• pp.92-97
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• 2012

This paper suggests a data gathering scheme using dynamic branch tree in wireless sensor networks. A mobile sink gathers data from each sensor node using a dynamic data gathering tree rooted at the mobile sink node. As the sink moves, a tree that has multiple branch is formed and changed dynamically as with the position of the sink node. A hop-based scope filter and a restricted flooding scheme of the tree are also suggested. Simulation results show that the proposed data gathering scheme has better results in data arrival rate, the end-to-end delay and energy saving characteristics compared with the previous scheme.

• The Monthly Diabetes
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• s.210
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• pp.14-16
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• 2007

65세 김모씨는 가족들과 외출을 하려다가 갑자기 발음이 어눌해 지면서 우측에 힘이 빠지기 시작하였다. 가족들은 일단 김씨를 다시 집안으로 데리고 들어와 팔 다리를 주므르고 바늘로 손을 따 보았지만 상태는 점점 악화되어 전혀 말도 못하고 일어설 수 도 없었으며 정신도 흐려지는 등 급속히 악화되었다. 김씨의 아들은 뇌졸중이 아닌가 하는 생각이 들었고 최근에 언론매체를 통해 혈관이 막히는 뇌졸중의 경우에 빨리 병원에 가면 막힌 혈관을 다시 뚫어주는 치료가 가능하다는 이야기를 들은 기억을 떠올렸다. 김씨의 아들은 119에 연락해 아버님을 응급실로 모시고 왔다. 김씨가 병원에 도착한 시간은 증상이 발생한 후 약 1시간 만이였다. 뇌촬영을 비롯한 피검사 등이 시행되었고 의료진은 김씨가 혈관이 막힌 뇌졸중, 즉 뇌경색이라고 하였고, 현재 발병한 지 채 2시간이 지나지 않았으므로 혈관을 뚫어주는 혈전용해술을 시행하겠다고 했다. 혈관이 막힌 원인은 오랫동안 가지고 있던 당뇨, 고혈압, 고지혈증 등이 복합적으로 작용하여 혈관에 동맥경화를 유발하고 있다가 혈전이 생기면서 혈관이 막힌 것이라고 하였다. 그리고 혈관을 막고 있는 혈전을 녹이기 위해 혈전용해술을 시행하는 것이라고 하였다. 뇌출혈등의 부작용이 일부에서 동반될 수 있지만 지금 상태에서 가장 최선의 치료는 혈전용해술이라 것이 의료진의 설명이었다. 다음날 김씨는 완벽하지는 않았지만 말하는 기능과 우측 팔다리 마비가 상당히 호전되었다. 1주일 후 김씨의 상태는 더욱 호전 되었고 열심히 재활치료를 받고 있었다. 김씨와 가족들은 의료진으로부터 꾸준히 재활치료를 하면서 3개월 후 정도면 이전과 거의 비슷한 상태로 회복될 수 있을 것이라는 희망적인 이야기를 들을 수 있었다.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.2
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• pp.419-426
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• 2018

Ecotourism refers to tourism that senses and observes superior natural resources, cultural resources and history around. Today, as the current leisure patterns of the people change, a healing trip to find nature is being activated. In this paper, we propose a platform design and construction for providing ecotourism information. In the proposed platform, first, the image file of the eco-tourism objects taken every day from the image capture device is collected, converted into a video, uploaded to the server, then, when the tourist arrives at the eco-tourism object, It is designed to be able to watch.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.3 s.30
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• pp.43-50
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• 2004

This study has an object of searching for appropriateness in applying the trip distribution model by studying the changes of the character of parameter which the model contains and by analyzing and evaluating trip distribution technique out of few steps of pre-estimate technique for the traffic demand through computer simulation centering around Kwangju. Method of this study is investigating the basic theory for trip distribution model and with this grounding, I rearranged it as research data for trip distribution model compatible for Kwangju, using data such as research data on actual state, the statistics annual report and basic plan for traffic full equipment of Kwangju. So, The most stable measure of the type of trip distribution of Kwangju city was produced in Fratar and Detroit model, however, gravity model has a little bit low reliance in sharing of estimation and actual survey although it is astringent in short period.

• The Journal of the Korea Contents Association
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• v.11 no.8
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• pp.459-467
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• 2011

BIS(Bus Information Systems) supplies the bus arrived time information for users in using BIT(Bus Information Terminal) installed on the bus stop. BIT is the device using peoples directly. So, BIT need a quick response when it flew. These are an important factor in the strategy of the BIS maintenance. BIT need a maintenance cost to operate smoothly. So, Suppose that commercial advertisement can be displayed on BIT screen in this study. And we researched an advertisement rates of the optimum level in using Contingent Valuation Method. In addition, we analyzed a characteristic of user's depending on each time using multinomial Logit Modeling method, and studied for BIT operation and ad. displaying strategy considered user's sex, ages and using times.

• Journal of Korea Multimedia Society
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• v.6 no.5
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• pp.831-841
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• 2003

In wireless ATM network, Mobile terminals must offer function and QoS such as terminal of wire ATM network. The fast notification of BS (Base Station) scheduler about ATM cells arriving in mobile terminals is a critical item of the ATM-based centrally controlled MAC protocol. But, Collision is arisen at process that several mobile terminals require data transmission by contention method through uplink and because of re-transmission by collision, throughput of decrease and transmission delay increases. In this paper, We propose the MAC protocol that decide optimized request mini-slot's number considering number of request terminal predicted as statistical and its posterior throughput. According to simulation result, could know that proposed protocol shows high performance delay and throughput.