• Title/Summary/Keyword: Time-variant

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Efficient Spatial Index for Mobile Software (모바일 소프트웨어를 위한 효율적인 공간 인덱스)

  • Oh, Byoung-Woo
    • Spatial Information Research
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    • v.16 no.1
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    • pp.113-127
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    • 2008
  • This paper proposes an efficient spatial index, named $AR^*$-tree(Area $R^*$-tree) which is a variant of the $R^*$-tree, for mobile software. A MBR(Minimum Bounding Rectangle) structure of the $AR^*$-tree has additional min and max values of area axis as well as x and y axes. The value of area axis is used to determine the significance of a spatial data. If area of a spatial data is large, then it is significant when drawing a map. To reduce complexity of a map on a small screen of mobile device, only significant spatial data can be found by the $AR^*$-tree. The result of a series of tests indicates that the $AR^*$-tree provides a method for control of readability of a map and guarantees an efficient performance at the same time.

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Robust Lane Detection Method Under Severe Environment (악 조건 환경에서의 강건한 차선 인식 방법)

  • Lim, Dong-Hyeog;Tran, Trung-Thien;Cho, Sang-Bock
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.5
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    • pp.224-230
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    • 2013
  • Lane boundary detection plays a key role in the driver assistance system. This study proposes a robust method for detecting lane boundary in severe environment. First, a horizontal line detects form the original image using improved Vertical Mean Distribution Method (iVMD) and the sub-region image which is under the horizontal line, is determined. Second, we extract the lane marking from the sub-region image using Canny edge detector. Finally, K-means clustering algorithm classifi left and right lane cluster under variant illumination, cracked road, complex lane marking and passing traffic. Experimental results show that the proposed method satisfie the real-time and efficient requirement of the intelligent transportation system.

Iconological Interpretation of Makeup depicted in Alexander McQueen's Collection (Alexander McQueen 컬렉션에 표현된 메이크업의 도상학적 해석)

  • Kim, Hyun-Mi;Kim, Sook-Hyun;Jang, Ae-Ran
    • Journal of the Korean Society of Costume
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    • v.60 no.10
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    • pp.118-132
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    • 2010
  • The purpose of the research is to develop a systematic model to interpret makeup signs through a case analysis of makeup shown in Alexander McQueen's ready-to-wear collections from 2001 to 2010 and to prove an importance of makeup as a communication medium to deliver social and cultural values. This research employed Panofsky's Iconology theory to analyze data. This theory consists of three steps to interpret the meaning of a work: (1) pre-iconographical description, (2) iconographical analysis, and (3) iconological interpretation. Alexander McQueen's makeup was analyzed with the three steps in order. As a result of the pre-iconographical description step, makeup styles (icons) in his collections are identified which are Egyptian style, Gothic style, Androgynous style, Victorian style, Fantasia style, and Futuristic variant style. The iconographical analysis step identified that the elements used in his makeup are inspired by his identity and life. In the final step of iconological interpretation, the researcher concluded that Alexander McQueen's makeup expresses social, cultural, and aesthetical value of the time period when the collection was created. His makeup shows postmodernism that accepts a diversity of views (the pluralism) and humanism, romantic narcissism that is his personality trait, and avant-garde that pursues a new, creative aesthetics.

Pade Approximation Based Adaptive Parameter Estimation for Radar Signal Active Cancellation (레이더 신호 능동 상쇄를 위한 Pade 근사 기반의 적응적 파라미터 추정 기법)

  • Lee, Sanggeun;Lim, Seongmok;Sim, Dongkyu;Lee, Chungyong
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.11
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    • pp.47-53
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    • 2014
  • We propose a parameter estimation algorithm for radar signal active cancellation based on the Pade approximation that requires much less samples than the conventional MLE scheme. We also verify that the radar signal with time-variant center frequency can be estimated with proposed algorithm by renovating the center frequency. We present simulation results for radar signal active cancellation to show the accuracy of estimated signal using proposed algorithm by calculating the ratio of RMSE of estimated signal to amplitude of hostile radar signal.

On the Filtering of Hangul character Element with the Spatial Positioning Modulation (공간 위치 변조에 의한 한글자소의 필터링)

  • 강대수;진용옥
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.17 no.9
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    • pp.1029-1039
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    • 1992
  • This paper presents the filtering method which is processed on the frequency domain among Hangul character recognition methods. It is processed the Hangul character parrern with spatial positioning modulation and mapped the Hangul character element which have spatial position variant feature onto frequency domain, at this time, normalized spatial position and so normalized the character size in frequency domain. And it is grouped the Hangul character element according to the generating position and set the standard pattern, and used each standard character element pattern with character element filter and filtering the character pattern of Hangul character, it is derived the normalized cross correlation function and the coherence function led to the filtering results, and calculated classification threshold.

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A Hybrid Transceiver for Underwater Acoustic Communication (수중음향 통신을 위한 혼합형 송수신기에 관한 연구)

  • Choi, Young-Chol;Kim, Sea-Moon;Park, Jong-Won;Kim, Seung-Geun;Lim, Yong-Gon;Kim, Sang-Tab
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2003.05a
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    • pp.319-323
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    • 2003
  • In this paper, we propose a hybrid transceiver for underwater acoustic communication, which allows the system to reduce complexity and increase robustness in time variant underwater channel environments. It is designed in the digital domain except for amplifiers and implemented by using a multiple digital signal processors (DSPs) system. The digital modulation technique is quadrature phase shift keying (QPSK) and frame synchronization is an energy (non-coherent) detection scheme based on the quadrature receiver structure. DSP implementation is based on block data parallel architecture (BDPA). We shaw experimental results in th? underwater anechoic basin at KRISO. The results indicate that the frame synchronization is performed without PLL. Also, we shaw that the adaptive equalizer can compensate frame synchronization error and the correction capability is dependent on the length of equalizer.

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Function and use of silkworm dpp gene (누에 유래의 dpp 유전자의 기능 및 유전체 연구를 통한 식의약용 신소재로서 활용)

  • Park, Seung Wong
    • Journal of Sericultural and Entomological Science
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    • v.54 no.1_2
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    • pp.1-5
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    • 2016
  • The dpp gene originated from the silkworms is an important gene that is well conserved in the genome of humans, cattle, rodents, poultry and Drosophila. The dpp gene belonging to the TGF-beta (Transforming Growth Factor-beta) superfamily is known to play an important role in several developmental stages. The $TGF-{\beta}$ gene family is a genetically well-conserved and playing an important role gene family in various species such as determining cell proliferation and differentiation, apoptosis and cell fate. In this review, we have confirmed the following studies data. The recent studies on the silkworm dpp gene have confirmed for the first time the biological functions such as promoting osteogenesis activity. In addition, previous data shows that dpp have developmental functions such as morphogenetic materials at the blastophyllum stage, induction of the mesoblast at the late embryonic stage and involved in the proliferation and morphogenesis of imaginal disc in adult development. We found the splice variant of the dpp gene originated from the wildtype silkworm by using comparative genomics. It has provided important data for basic research based on genetics studies of these processes may promote a better understanding of evolution. Silkworm is a medicinal insect and is approved for its safety. It is used as a natural antibiotic for promoting growth as a medical material, a health functional food, and a feed additive. Therefore, it is necessary to present various data to obtain more value of functional insect.

Structural Analysis of a Tire using an ANSYS Workbench (ANSYS Workbench를 활용한 타이어 구조 해석)

  • Han, Cheolheui
    • Journal of Institute of Convergence Technology
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    • v.1 no.1
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    • pp.9-12
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    • 2011
  • Structural analysis of a tire is done using a commercial software, ANSYS Workbench. The properties of rubber of the tire is represented using a Mooney-Rivlin model. The bead in the tire is made of structural steel. 3D CAD model of the tire is obtained from a commercial CAD-specialized software, CATIA. Using an imported 3D CAD geometric model, a mesh system with fifty thousand nodes is constructed using ANSYS. A time-variant point force is applied to the rim of the tire, and the deformation of the tire is computed. It is found that both bending and twisting of the tire are observed where the point force is applied. The deformation of the tire is asymmetric, which results in the help of ripping the tire using the helper. It is also found that the deformation undergoes linearly with the applied force. When the force is larger than 1500N, then the deformation becomes larger than the half of the thickness of the tire. In the future, a more realistic rubber model will be applied and validated with the measured data.

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DLDW: Deep Learning and Dynamic Weighing-based Method for Predicting COVID-19 Cases in Saudi Arabia

  • Albeshri, Aiiad
    • International Journal of Computer Science & Network Security
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    • v.21 no.9
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    • pp.212-222
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    • 2021
  • Multiple waves of COVID-19 highlighted one crucial aspect of this pandemic worldwide that factors affecting the spread of COVID-19 infection are evolving based on various regional and local practices and events. The introduction of vaccines since early 2021 is expected to significantly control and reduce the cases. However, virus mutations and its new variant has challenged these expectations. Several countries, which contained the COVID-19 pandemic successfully in the first wave, failed to repeat the same in the second and third waves. This work focuses on COVID-19 pandemic control and management in Saudi Arabia. This work aims to predict new cases using deep learning using various important factors. The proposed method is called Deep Learning and Dynamic Weighing-based (DLDW) COVID-19 cases prediction method. Special consideration has been given to the evolving factors that are responsible for recent surges in the pandemic. For this purpose, two weights are assigned to data instance which are based on feature importance and dynamic weight-based time. Older data is given fewer weights and vice-versa. Feature selection identifies the factors affecting the rate of new cases evolved over the period. The DLDW method produced 80.39% prediction accuracy, 6.54%, 9.15%, and 7.19% higher than the three other classifiers, Deep learning (DL), Random Forest (RF), and Gradient Boosting Machine (GBM). Further in Saudi Arabia, our study implicitly concluded that lockdowns, vaccination, and self-aware restricted mobility of residents are effective tools in controlling and managing the COVID-19 pandemic.

Heuristics for Rich Vehicle Routing Problem : A Case of a Korean Mixed Feed Company (다특성 차량경로문제에 대한 휴리스틱 알고리즘 : 국내 복합사료 업체 사례)

  • Son, Dong Hoon;Kim, Hwa-Joong
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.42 no.1
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    • pp.8-20
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    • 2019
  • The vehicle routing problem is one of the vibrant research problems for half a century. Many studies have extensively studied the vehicle routing problem in order to deal with practical decision-making issues in logistics. However, developments of new logistics strategies have inevitably required investigations on solution methods for solving the problem because of computational complexity and inherent constraints in the problem. For this reason, this paper suggests a simulated annealing (SA) algorithm for a variant of vehicle routing problem introduced by a previous study. The vehicle routing problem is a multi-depot and multi-trip vehicle routing problem with multiple heterogeneous vehicles restricted by the maximum permitted weight and the number of compartments. The SA algorithm generates an initial solution through a greedy-type algorithm and improves it using an enhanced SA procedure with three local search methods. A series of computational experiments are performed to evaluate the performance of the heuristic and several managerial findings are further discussed through scenario analyses. Experiment results show that the proposed SA algorithm can obtain good solutions within a reasonable computation time and scenario analyses show that a transportation system visiting non-dedicated factories shows better performance in truck management in terms of the numbers of vehicles used and trips for serving customer orders than another system visiting only dedicated factories.