• Title/Summary/Keyword: implementation algorithm

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A Study on the Implementation of an optimized Algorithm for association rule mining system using Fuzzy Utility (Fuzzy Utility를 활용한 연관규칙 마이닝 시스템을 위한 알고리즘의 구현에 관한 연구)

  • Park, In-Kyu;Choi, Gyoo-Seok
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.20 no.1
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    • pp.19-25
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    • 2020
  • In frequent pattern mining, the uncertainty of each item is accompanied by a loss of information. AAlso, in real environment, the importance of patterns changes with time, so fuzzy logic must be applied to meet these requirements and the dynamic characteristics of the importance of patterns should be considered. In this paper, we propose a fuzzy utility mining technique for extracting frequent web page sets from web log databases through fuzzy utility-based web page set mining. Here, the downward closure characteristic of the fuzzy set is applied to remove a large space by the minimum fuzzy utility threshold (MFUT)and the user-defined percentile(UDP). Extensive performance analyses show that our algorithm is very efficient and scalable for Fuzzy Utility Mining using dynamic weights.

Implementation of Active Sound Enrichment Control for Improving Engine Sound Quality Inside the Cabin of a Passenger Car (차량 실내공간의 가속 시 엔진음 음질 향상을 위한 실시간 능동음향증강 제어 구현)

  • Lee, Young-Sup;Kim, Jeakwan;Ryu, Seokhoon;Kim, Seonghyeon;Park, Dong Chul
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.26 no.2
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    • pp.195-202
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    • 2016
  • In this study, a concept of active sound enrichment (ASE) control system was implemented and demonstrated for improving engine sound quality inside the cabin of a passenger car during acceleration. Unlike the active noise control cancels the noise for disturbance rejection, the ASE adds additional sound to the noise for tracking control. This approach requires a new algorithm to provide additional artificial sound to the original engine sound using active control strategy to achieve a target sound profile, which is predefined to satisfy required interior sound quality. The ASE algorithm was implemented in a digital controller dSPACE DS1401 and real-time control experiment was accomplished in an actual car. The ASE control results show that the actively enriched sound of each engine order against RPM tracks the target profiles precisely and quickly and improves the discontinuity, the level ratios and the sound pressure level of each engine order. Thus it is anticipated the ASE system can be applied for the improvement of the engine sound quality inside the cabin during acceleration.

The Strategy for Interconnection Branch Line Construction used Optimization Program (최적화 기법을 적용한 효율적인 철도 연결선 구축 전략)

  • Kim, Yong-seok;Kim, Sigon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.39 no.6
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    • pp.853-858
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    • 2019
  • One of the methods which can enhance the efficiency of railroad network is construction of interconnection branch line for several route to share one railway. In Korea, this method already has been implemented or excuted as project level. This study suggests a network design model and a solution algorithm to choice most proper site to construction it and determine the priority of branch lines which can be considered in planning level, not project level. The model is a non-linear optimization program which minimize total cost-construction cost, operating cost and passengers' travel cost. The decision variables are a binary variable to explain whether construction or not and its direction and a integer variable of the frequencies of travel routes. The solution algorithm-problem solution and route choice and also the result of implementation for example network are suggested. This result can be more advanced after application in real network and calibration of parameters.

A Study on the Secure Communication at Android Things Environment using the SEED Library (SEED 암호 라이브러리를 활용한 안전한 Android Things 통신 환경연구)

  • Park, Hwa Hyeon;Yoon, Mi Kyung;Lee, Hyeon Ju;Lee, Hae Young;Kim, Hyung-Jong
    • Journal of the Korea Society for Simulation
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    • v.28 no.4
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    • pp.67-74
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    • 2019
  • As the market for Internet of Things (IoT) service grows, the security issue of the data from IoT devices becomes more important. In this paper, we implemented a cryptographic library for confidentiality of sensor data from Android Things based IoT services. The library made use of the SEED algorithm for encryption/decryption of data and we verified the library by implementing a service environment. With the library, the data is securely encrypted and stored in the database and the service environment is able to represent the current sensing status with the decrypted sensor data. The contribution of this work is in verifying the usability of SEED based encryption library by implementation in IoT sensor based service environment.

Implementation of Improved Ship Positioning Algorithm using Sextant (섹스탄트를 이용한 개선된 선박 측위 알고리즘의 구현)

  • Shin, Heui-han;Yim, Jae-hong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.6
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    • pp.1243-1251
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    • 2017
  • When a Ship sails in the ocean, it is significant to find one's position for safe navigation. Most of ships have been using GPS navigation since its development after 1990's. The celestial navigation was used as the navigation method when sailing in the ocean, but time-consuming process such as complicated calculation and plotting the result on chart diminished its utilization. The thesis explains convenience and utilization of existing celestial navigation by resolving challenges it has. As a way of enhancing the celestial navigation, the author developed a software which incudes a numerical formula based on the previous calculation process. When a navigator inputs the altitude of sun, GHA and dec into computer while sailing, the position of the ship will be displayed as the coordinates. The improved method thus reaffirmed the usefulness of the celestial navigation and will greatly serve as means of navigation in the occurrence of distress. Abstract should be placed here.

Hardware Design of Real-Time Wide Dynamic Range Algorithm Based on Tone Mapping Method for Image Quality Enhancement (영상 품질 향상을 위한 색 사상 기반 실시간 광역역광보정 알고리즘의 하드웨어 설계)

  • Kim, Geun-Jun;Kang, Bongsoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.2
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    • pp.270-275
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    • 2018
  • Method for improving the image quality are divided into a tone mapping method and a retinex theory based method. Typical example of the image quality enhancement method using tone mapping method is one using image characteristics like histogram. In this paper, we propose a hardware design of real-time wide dynamic range algorithm based on tone mapping method for image quality enhancement. The proposed method divides the image into the luminance and chroma components and then improves the chroma region based on the variation of the luminance component. Adding to that, it is designed to be compatible with the existing 8-bit signal, using high quality image with 12-bit extended signal according to the desired flow. As a result of simulation, it is confirmed that the image quality is improved, and the hardware design is confirmed that the real-time operations is possible at the maximum frequency at 138.26MHz.

SPARQL-DL Processor to Extract OWL Ontologies from Relational Databases (관계형 데이터베이스로부터 OWL 온톨로지를 추출하기 위한 SPARQL-DL 프로세서)

  • Choi, Ji-Woong;Kim, Myung-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.20 no.3
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    • pp.29-45
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    • 2015
  • This paper proposes an implementation of SPARQL-DL, which is a query language for OWL ontologies, for query-answering over the OWL ontologies virtually generated from existing RDBs. The proposed SPARQL-DL processor internally translates input SPARQL-DL queries into SQL queries and then executes the translated queries. There are two advantages in the query processing method. First, another repository to store OWL ontologies generated from RDBs is not required. Second, a large ABox generated from an RDB instance is able to be served without using Tableau algorithm based reasoners which have a problem in large ABox reasoning. Our algorithm for query rewriting is designed to create one corresponding SQL query from one input SPARQL-DL query to minimize the overhead by establishing connections with RDBs.

A Fast Sorting Strategy Based on a Two-way Merge Sort for Balancing the Capacitor Voltages in Modular Multilevel Converters

  • Zhao, Fangzhou;Xiao, Guochun;Liu, Min;Yang, Daoshu
    • Journal of Power Electronics
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    • v.17 no.2
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    • pp.346-357
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    • 2017
  • The Modular Multilevel Converter (MMC) is particularly attractive for medium and high power applications such as High-Voltage Direct Current (HVDC) systems. In order to reach a high voltage, the number of cascaded submodules (SMs) is generally very large. Thus, in the applications with hundreds or even thousands of SMs such as MMC-HVDCs, the sorting algorithm of the conventional voltage balancing strategy is extremely slow. This complicates the controller design and increases the hardware cost tremendously. This paper presents a Two-Way Merge Sort (TWMS) strategy based on the prediction of the capacitor voltages under ideal conditions. It also proposes an innovative Insertion Sort Correction for the TWMS (ISC-TWMS) to solve issues in practical engineering under non-ideal conditions. The proposed sorting methods are combined with the features of the MMC-HVDC control strategy, which significantly accelerates the sorting process and reduces the implementation efforts. In comparison with the commonly used quicksort algorithm, it saves at least two-thirds of the sorting execution time in one arm with 100 SMs, and saves more with a higher number of SMs. A 501-level MMC-HVDC simulation model in PSCAD/EMTDC has been built to verify the validity of the proposed strategies. The fast speed and high efficiency of the algorithms are demonstrated by experiments with a DSP controller (TMS320F28335).

Vehicular Cooperative Navigation Based on H-SPAWN Using GNSS, Vision, and Radar Sensors (GNSS, 비전 및 레이더를 이용한 H-SPAWN 알고리즘 기반 자동차 협력 항법시스템)

  • Ko, Hyunwoo;Kong, Seung-Hyun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.11
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    • pp.2252-2260
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    • 2015
  • In this paper, we propose a vehicular cooperative navigation system using GNSS, vision sensor and radar sensor that are frequently used in mass-produced cars. The proposed cooperative vehicular navigation system is a variant of the Hybrid-Sum Product Algorithm over Wireless Network (H-SPAWN), where we use vision and radar sensors instead of radio ranging(i.e.,UWB). The performance is compared and analyzed with respect to the sensors, especially the position estimation error decreased about fifty percent when using radar compared to vision and radio ranging. In conclusion, the proposed system with these popular sensors can improve position accuracy compared to conventional cooperative navigation system(i.e.,H-SPAWN) and decrease implementation costs.

A Frequency Domain based Positioning Method using Auto Regressive Modeling in LR-WPAN (주파수 영역상의 AR 모델링 기반 이용한 LR-WPAN용 무선측위기법)

  • Hong, Yun-Gi;Bae, Seung-Chun;Choi, Sung-Soo;Lee, Won-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.6C
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    • pp.561-570
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    • 2009
  • Ultra-wideband communication systems based on impulse radio have merits that are possible for the high data rate transmission, high resolution ranging are positioning system. Conventionally, in order to accomplish these features, the high-speed ADC (Analog to Digital Convertor) is necessary to apply radio determination system operating in time domain. However, considering low rate - wireless personal area network (LR-WPAN) aims to low-cost hardware implementation, the expensive ADC converting GHz sampling per second is not appropriate. So, this paper introduces a low complex AR (Auto Regressive) model based non-coherent ranging scheme operating in frequency domain with using low-speed ADC utilizing analog Voltage Control Oscillator (VCO) mode for the frequency domain transformation. To verify the superiority of the proposed ranging and location algorithm working in frequency domain, the suggested IEEE 802.15.4a TG channel model is used to exploit affirmative features of the proposed algorithm with conducting the simulation results.