• Title/Summary/Keyword: A* algorithm

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Development of Freeway Traffic Incident Clearance Time Prediction Model by Accident Level (사고등급별 고속도로 교통사고 처리시간 예측모형 개발)

  • LEE, Soong-bong;HAN, Dong Hee;LEE, Young-Ihn
    • Journal of Korean Society of Transportation
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    • v.33 no.5
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    • pp.497-507
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    • 2015
  • Nonrecurrent congestion of freeway was primarily caused by incident. The main cause of incident was known as a traffic accident. Therefore, accurate prediction of traffic incident clearance time is very important in accident management. Traffic accident data on freeway during year 2008 to year 2014 period were analyzed for this study. KNN(K-Nearest Neighbor) algorithm was hired for developing incident clearance time prediction model with the historical traffic accident data. Analysis result of accident data explains the level of accident significantly affect on the incident clearance time. For this reason, incident clearance time was categorized by accident level. Data were sorted by classification of traffic volume, number of lanes and time periods to consider traffic conditions and roadway geometry. Factors affecting incident clearance time were analyzed from the extracted data for identifying similar types of accident. Lastly, weight of detail factors was calculated in order to measure distance metric. Weight was calculated with applying standard method of normal distribution, then incident clearance time was predicted. Prediction result of model showed a lower prediction error(MAPE) than models of previous studies. The improve model developed in this study is expected to contribute to the efficient highway operation management when incident occurs.

Development of integrative diagnosis methods for the jaundice through statistical analysis (통합의료적 황달진단법개발을 위한 통계적 접근방법)

  • Shin, Im Hee;Kwak, Sang Gyu;Kim, Sang Gyung;Sohn, Ki Cheul;Jung, Hyun-Jung;Cho, Yoon-Jeong;Lee, A-Jin;Kwon, O Sung
    • Journal of the Korean Data and Information Science Society
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    • v.24 no.3
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    • pp.515-521
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    • 2013
  • Healthcare approach in Western medicine and Korean Traditional Medicine (KTM) varies from its nature of human understanding and cultural differences. This fundamental difference in their approach of the human pathology has dualised and hindered common medical communication between the two fields of medicines. Within this current difficulty, the integrative medical service is said to become a novel method to provide the patients with the best medical care as their intent is to adapt and combine the advantages stated from the two different fields. This research paper shows the integrative approach of treating jaundice, where the symptoms of dampness and heat on Korean traditional standards are analyzed using statistical methods based on monitoring the blood test results. Therefore, we can explore an approach to diagnose and treat with comprehensive and integrative medicine algorithm.

Ciphering Scheme and Hardware Implementation for MPEG-based Image/Video Security (DCT-기반 영상/비디오 보안을 위한 암호화 기법 및 하드웨어 구현)

  • Park Sung-Ho;Choi Hyun-Jun;Seo Young-Ho;Kim Dong-Wook
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.2 s.302
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    • pp.27-36
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    • 2005
  • This thesis proposed an effective encryption method for the DCT-based image/video contents and made it possible to operate in a high speed by implementing it as an optimized hardware. By considering the increase in the amount of the calculation in the image/video compression, reconstruction and encryption, an partial encryption was performed, in which only the important information (DC and DPCM coefficients) were selected as the data to be encrypted. As the result, the encryption cost decreased when all the original image was encrypted. As the encryption algorithm one of the multi-mode AES, DES, or SEED can be used. The proposed encryption method was implemented in software to be experimented with TM-5 for about 1,000 test images. From the result, it was verified that to induce the original image from the encrypted one is not possible. At that situation, the decrease in compression ratio was only $1.6\%$. The hardware encryption system implemented in Verilog-HDL was synthesized to find the gate-level circuit in the SynopsysTM design compiler with the Hynix $0.25{\mu}m$ CMOS Phantom-cell library. Timing simulation was performed by Verilog-XL from CadenceTM, which resulted in the stable operation in the frequency above 100MHz. Accordingly, the proposed encryption method and the implemented hardware are expected to be effectively used as a good solution for the end-to-end security which is considered as one of the important problems.

Fabrication of IMT-2000 Linear Power Amplifier using Current Control Adaptation Method in Signal Cancelling Loop (신호 제거 궤환부의 전류 제어 적응형 알고리즘을 이용한 IMT-2000용 선형화 증폭기 제작)

  • 오인열;이창희;정기혁;조진용;라극한
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.40 no.1
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    • pp.24-36
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    • 2003
  • The digital mobile communication will be developed till getting multimedia service in anyone, any where, any time. Theses requiring items are going to be come true via IMT-2000 system. Transmitting signal bandwidth of IMT-2000 system is 3 times as large as IS-95 system. That is mean peak to average of signal is higher than IS-95A system. So we have to design it carefully not to effect in adjacent channel. HPA(High Power Amplifier) located in the end point of system is operated in 1-㏈ compression point(Pl㏈), then it generates 3rd and 5th inter modulation signals. Theses signals affect at adjacent channel and RF signal is distorted by compressed signal which is operated near by Pl㏈ point. Then the most important design factor is how we make HPA having high linearity. Feedback, Pre-distorter and Feed-forward methods are presented to solve theses problems. Feed-forward of these methods is having excellent improving capacity, but composed with complex structure. Generally, Linearity and Efficiency in power amplifier operate in the contrary, then it is difficult for us to find optimal operating point. In this paper we applied algorithm which searches optimal point of linear characteristics, which is key in Power Amplifier, using minimum current point of error amplifier in 1st loop. And we made 2nd loop compose with new structure. We confirmed fabricated LPA is operated by having high linearity and minimum current condition with ACPR of -26 ㏈m max. @ 30㎑ BW in 3.515㎒ and ACLR of 48 ㏈c max@${\pm}$㎒ from 1W to 40W.

Efficiency Algorithm of Multispectral Image Compression in Wavelet Domain (웨이브릿 영역에서 다분광 화상데이터의 효율적인 압축 알고리듬)

  • Ban, Seong-Won;Seok, Jeong-Yeop;Kim, Byeong-Ju;Park, Gyeong-Nam;Kim, Yeong-Chun;Jang, Jong-Guk;Lee, Geon-Il
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.38 no.4
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    • pp.362-370
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    • 2001
  • In this paper, we proposed multispectral image compression method using CIP (classified inter-channel prediction) and SVQ (selective vector quantization) in wavelet domain. First, multispectral image is wavelet transformed and classified into one of three classes considering reflection characteristics of the subband with the lowest resolution. Then, for a reference channel which has the highest correlation and the same resolution with other channels, the variable VQ is performed in the classified intra-channel to remove spatial redundancy. For other channels, the CIP is performed to remove spectral redundancy. Finally, the prediction error is reduced by performing SVQ. Experiments are carried out on a multispectral image. The results show that the proposed method reduce the bit rate at higher reconstructed image quality and improve the compression efficiency compared to conventional methods. Index Terms-Multispectral image compression, wavelet transform, classfied inter-channel prediction, selective vetor quantization, subband with lowest resolution.

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R-Tree Construction for The Content Based Publish/Subscribe Service in Peer-to-peer Networks (피어투피어 네트워크에서의 컨텐츠 기반 publish/subscribe 서비스를 위한 R-tree구성)

  • Kim, Yong-Hyuck;Kim, Young-Han;Kang, Nam-Hi
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.46 no.11
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    • pp.1-11
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    • 2009
  • A content based pub/sub (Publish/subscribe) services at the peer-to-peer network has the requirements about how to distribute contents information of subscriber and to delivery the events efficiently. For satisfying the requirements, a DHT(Distributed Hash Table) based pub/sub overlay networking and tree type topology based network construction using filter technique have been proposed. The DHT based technique is suitable for topic based pub/sub service but it's not good contents based service that has the variable requirements. And also filter based tree topology networking is not efficient at the environment where the user requirements are distributed. In this paper we propose the R-Tree algorithm based pub/sub overlay network construction method. The proposed scheme provides cost effective event delivery method by mapping user requirement to multi-dimension and hierarchical grouping of the requirements. It is verified by simulation at the variable environment of user requirements and events.

Development of 3D Radiation Position Identification System of Multiple Radiation Sources using Plastic Scintillator and NaI(TI) Detector (플라스틱 Scintillator와 NaI(TI) 검출기를 이용한 다수의 방사선원 위치를 3차원으로 판별하는 측정시스템 개발)

  • Kwak, Dong-Hoon;Ko, Tae-Young;Lee, Seung-Ho
    • Journal of IKEEE
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    • v.22 no.3
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    • pp.638-644
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    • 2018
  • In this paper, we develop a measurement system that uses 3D Scintillator and NaI(TI) Detector to 3-dimensionally identify the location of multiple radiation sources in moving vehicle loads. The radiation measurement system consists of radiation measurement (plastic scintillator), 2-channel Pulse Counter Board, nuclide analysis (NaI(TI) detector) and 1 channel MCA Board. The source locator algorithm calculates the coordinate value of the ratio of the CPS value($1/r^2$) of the source according to the angle(${\theta}$) in inverse proportion to the square of the distance(X, Y) through the SVM classification. The coordinate values are input every predetermined period of the spectrum, and after analyzing the spectrum per unit cycle, the position of the nuclide at the time is calculated by determining whether or not the nuclide is present in the remaining part except for the background area. As a result of the position discrimination test, the error within the international standard of ${\pm}1m$ was shown. Thus, the utility of the proposed system has been demonstrated.

Design and Implementation Stereo Camera based Twin Camera Module System (스테레오 카메라 기반 트윈 카메라 모듈 시스템 설계 및 구현)

  • Kim, Tae-Yeun
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.12 no.6
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    • pp.537-546
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    • 2019
  • The paper actualizes the twin camera module system that is portable and very useful for the production of 3D contents. The suggested twin camera module system is a system to be able to display the 3D image after converting the inputted image from 2D stereo camera. To evaluate the performance of the twin camera module suggested in this paper, I assessed the correction of Rotation and Tilt created depending on the visual difference between the left and right stereoscopic image shot by the left and right lenses by using the Test Platform. In addition, I verified the efficiency of the twin camera module system through verifying Depth Error of 3D stereoscopic image by means of Scale Invariant Feature Transform(SIFT) algorithm. I think that if the user utilizes the suggested twin camera module system in displaying the image to the external after converting the shot image into the 3D stereoscopic image and the preparation image, it is possible to display the image in a matched way with an output device fit respectively for different 3D image production methods and if the user utilizes the system in displaying the created image in the form of the 3D stereoscopic image and the preparation image via different channels, it is possible to produce 3D image contents easily and conveniently with applying to lots of products.

Planning and Dosimetric Study of Volumetric Modulated Arc Based Hypofractionated Stereotactic Radiotherapy for Acoustic Schwannoma - 6MV Flattening Filter Free Photon Beam

  • Swamy, Shanmugam Thirumalai;Radha, Chandrasekaran Anu;Arun, Gandhi;Kathirvel, Murugesan;Subramanian, Sai
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.12
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    • pp.5019-5024
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    • 2015
  • Background: The purpose of this study was to assess the dosimetric and clinical feasibility of volumetric modulated arc based hypofractionated stereotactic radiotherapy (RapidArc) treatment for large acoustic schwannoma (AS >10cc). Materials and Methods: Ten AS patients were immobilized using BrainLab mask. They were subject to multimodality imaging (magnetic resonance and computed tomography) to contour target and organs at risk (brainstem and cochlea). Volumetric modulated arc therapy (VMAT) based stereotactic plans were optimized in Eclipse (V11) treatment planning system (TPS) using progressive resolution optimizer-III and final dose calculations were performed using analytical anisotropic algorithm with 1.5 mm grid resolution. All AS presented in this study were treated with VMAT based HSRT to a total dose of 25Gy in 5 fractions (5fractions/week). VMAT plan contains 2-4 non-coplanar arcs. Treatment planning was performed to achieve at least 99% of PTV volume (D99) receives 100% of prescription dose (25Gy), while dose to OAR's were kept below the tolerance limits. Dose-volume histograms (DVH) were analyzed to assess plan quality. Treatments were delivered using upgraded 6 MV un-flattened photon beam (FFF) from Clinac-iX machine. Extensive pretreatment quality assurance measurements were carried out to report on quality of delivery. Point dosimetry was performed using three different detectors, which includes CC13 ion-chamber, Exradin A14 ion-chamber and Exradin W1 plastic scintillator detector (PSD) which have measuring volume of $0.13cm^3$, $0.009cm^3$ and $0.002cm^3$ respectively. Results: Average PTV volume of AS was 11.3cc (${\pm}4.8$), and located in eloquent areas. VMAT plans provided complete PTV coverage with average conformity index of 1.06 (${\pm}0.05$). OAR's dose were kept below tolerance limit recommend by American Association of Physicist in Medicine task group-101(brainstem $V_{0.5cc}$ < 23Gy, cochlea maximum < 25Gy and Optic pathway <25Gy). PSD resulted in superior dosimetric accuracy compared with other two detectors (p=0.021 for PSD.

Digital Tomosynthesis for Patient Alignment System Using Half-fan Mode CBCT Projection Images (Half-fan 모드를 이용한 방사선치료환자 위치교정을 위한 디지털영상 합성영상기술에 관한 예비연구)

  • Park, Justin C.;Park, Sung-Ho;Kim, Jin-Sung;Han, Young-Yih;Ju, Sang-Gyu;Shin, Eun-Hyuk;Shin, Jung-Suk;Park, Hee-Chul;Ahn, Yong-Chan;Song, Willian Y.
    • Progress in Medical Physics
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    • v.21 no.4
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    • pp.360-366
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    • 2010
  • To generate on-board digital tomosynthesis (DTS) for three-dimensionalimage-guided radiation therapy (IGRT) as an alternative to conventional portal imaging or on-board cone-beam computed tomography (CBCT), two clinical cases (liver and bladder) were selected to illustrate the capabilities of on-board DTS for IGRT. DTS images were generated from subsets of CBCT projection data (45, 162 projections) using half-fan mode scanning with a Feldkamp-type reconstruction algorithm. Digital tomosynthesis slices appeared similar to coincident CBCT planes and yielded substantially more anatomic information. Improved bony and soft-tissue visibility in DTS images is likely to improve target localization compared with radiographic verification techniques and might allow for daily localization of a soft-tissue target. Digital tomosynthesis might allow targeting of the treatment volume on the basis of daily localization.