• 제목/요약/키워드: hybrid science

검색결과 3,991건 처리시간 0.028초

Hybrid PSO-Complex Algorithm Based Parameter Identification for a Composite Load Model

  • Del Castillo, Manuelito Y. Jr.;Song, Hwachang;Lee, Byongjun
    • Journal of Electrical Engineering and Technology
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    • 제8권3호
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    • pp.464-471
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    • 2013
  • This paper proposes a hybrid searching algorithm based on parameter identification for power system load models. Hybrid searching was performed by the combination of particle swarm optimization (PSO) and a complex method, which enhances the convergence of solutions closer to minima and takes advantage of global searching with PSO. In this paper, the load model of interest is composed of a ZIP model and a third-order model for induction motors for stability analysis, and parameter sets are obtained that best-fit the output measurement data using the hybrid search. The origin of the hybrid method is to further apply the complex method as a local search for finding better solutions using the selected particles from the performed PSO procedure.

High Precision Pressure Control of a Pneumatic Chamber using a Hybrid Fuzzy PID Controller

  • Liu, Hao;Lee, Jae-Cheon;Li, Bao-Ren
    • International Journal of Precision Engineering and Manufacturing
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    • 제8권3호
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    • pp.8-13
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    • 2007
  • A hybrid fuzzy PID controller for a pneumatic chamber is proposed in this paper. First, a mathematical model of a pneumatic pressure servocontrol system was developed where separate implementations of a PID controller and a fuzzy controller were made. The experimental results using a step input signal revealed that the PID controller accurately controlled the steady-state pressure but did not robustly handle parameter variations in the system while the fuzzy controller provided a fast rise time and low overshoot of the pressure in the system. In order to attain the advantages of both the fuzzy and PID controllers, a hybrid control scheme was developed. The experimental results show that the hybrid fuzzy PID controller proposed in this study does indeed possess the advantages of both PID and fuzzy controllers. Hence, it can be concluded that the hybrid fuzzy PID controller is suited for high-precision control of pressure in a pneumatic chamber.

Antihypertensive Angiotensin I-Converting Enzyme Inhibitory Activity and Antioxidant Activity of Vitis hybrid-Vitis coignetiae Red Wine Made with Saccharomyces cerevisiae

  • Jang, Jeong-Hoon;Lee, Jong-Soo
    • Mycobiology
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    • 제39권2호
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    • pp.137-139
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    • 2011
  • A Vitis hybrid-Vitis coignetiae red wine was vinified by fermentation of a mixture of a Vitis hybrid.Vitis coignetiae must with Saccharomyces cerevisiae KCTC 7904 at $25^{\circ}C$ for 10 days. The Vitis hybrid-Vitis coignetiae red wine showed high antihypertensive angiotensin I-converting enzyme (ACE) inhibitory activity (67.8%) and antioxidant activity (76.7%). The antihypertensive ACE inhibitor in the Vitis hybrid-Vitis coignetiae red wine was partially purified by solid phase extraction chromatography, and its ACE inhibitory activity yielded an $IC_{50}$ of 1.8 mg/mL. Six kinds of oligopeptides, including five new kinds, were contained in the partially purified ACE inhibitor fraction from the red wine after 10 days of fermentation. Antioxidant activity decreased significantly from 76.7% to 40.5% when the post-fermentation period was prolonged to 30 days.

Nicotiana tabacum과 N. rustica 체세포 잡종식물의 육성 (Somatic hybridization between Nicotiana rustica and N. tabacum through protoplast fusion)

  • 최상주;이승철;홍병희
    • 한국연초학회지
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    • 제15권2호
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    • pp.123-129
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    • 1993
  • Mesophyll protoplasts derived from young leaves of Nicotiana rustica and N. tabacum cv Burley 21 were fused with the aid of polyethylene glycol(PEG). Cytological examination of protoplasts after PEG treatment revealed 12.8 % heterokaryocytes. After 7 weeks culture, the hybrid calli showing greenish white with a compact appearance were selected in contrast to parental type calli tinged with white or green color. The somatic hybrid plants were verified by morphological, biochemical and cyclological analysis. A heterosis effect for plant vigor and height was observed but the shape of leaves and flower characteristics were intermediate between N. tabacum and N. rutstica. The isozyme banding patterns for peroxidase of somatic hybrid lines were compared with the parent species. A number of isozyme bands derived from both parental species were found in the hybrids. Somatic hybrid plants have been successfully backcrossed to the parental N. tabacum particularly with somatic hybrid plants as female parents. These hybrid plants yielded small seeds, only few which were germinable.

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Estimation of the exponential distribution based on multiply Type I hybrid censored sample

  • Lee, Kyeongjun;Sun, Hokeun;Cho, Youngseuk
    • Journal of the Korean Data and Information Science Society
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    • 제25권3호
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    • pp.633-641
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    • 2014
  • The exponential distibution is one of the most popular distributions in analyzing the lifetime data. In this paper, we propose multiply Type I hybrid censoring. And this paper presents the statistical inference on the scale parameter for the exponential distribution when samples are multiply Type I hybrid censoring. The scale parameter is estimated by approximate maximum likelihood estimation methods using two different Taylor series expansion types ($AMLE_I$, $AMLE_{II}$). We also obtain the maximum likelihood estimator (MLE) of the scale parameter ${\sigma}$ under the proposed multiply Type I hybrid censored samples. We compare the estimators in the sense of the root mean square error (RMSE). The simulation procedure is repeated 10,000 times for the sample size n=20 and 40 and various censored schemes. The $AMLE_{II}$ is better than $AMLE_I$ in the sense of the RMSE.

Colloidally stable organic-inorganic hybrid nanoparticles prepared using alkoxysilane-functionalized amphiphilic polymer precursors and mechanical properties of their cured coating film

  • Kim, Nahae;Li, Xinlin;Kim, Se Hyun;Kim, Juyoung
    • Journal of Industrial and Engineering Chemistry
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    • 제68권
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    • pp.209-219
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    • 2018
  • Colloidally stable organic-inorganic (O-I) hybrid nanoparticles could be prepared using an alkoxysilanefunctionalized amphiphilic polymer (AFAP) precursor. O-I hybrid sols could maintain colloidal stability for six months even at 45% solid content and be coated onto glass as well as PET film to form transparent O-I hybrid films. The formation of O-I hybrid nanoparticles dispersed in cured coating films could be confirmed using scanning electron microscopy. The cured coating film showed 3H and 5H pencil hardness on PET and glass, respectively. Nanoindentation measurements also showed that their modulus and hardness was varied with the type of AFAP used in its preparation.

A Hybrid Learning Model to Detect Morphed Images

  • Kumari, Noble;Mohapatra, AK
    • International Journal of Computer Science & Network Security
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    • 제22권6호
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    • pp.364-373
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    • 2022
  • Image morphing methods make seamless transition changes in the image and mask the meaningful information attached to it. This can be detected by traditional machine learning algorithms and new emerging deep learning algorithms. In this research work, scope of different Hybrid learning approaches having combination of Deep learning and Machine learning are being analyzed with the public dataset CASIA V1.0, CASIA V2.0 and DVMM to find the most efficient algorithm. The simulated results with CNN (Convolution Neural Network), Hybrid approach of CNN along with SVM (Support Vector Machine) and Hybrid approach of CNN along with Random Forest algorithm produced 96.92 %, 95.98 and 99.18 % accuracy respectively with the CASIA V2.0 dataset having 9555 images. The accuracy pattern of applied algorithms changes with CASIA V1.0 data and DVMM data having 1721 and 1845 set of images presenting minimal accuracy with Hybrid approach of CNN and Random Forest algorithm. It is confirmed that the choice of best algorithm to find image forgery depends on input data type. This paper presents the combination of best suited algorithm to detect image morphing with different input datasets.

The Design of Calculable Standard Dipole Antennas in the Frequency Range of 1~3 GHz

  • Kim, Ki-Chai;Kim, Sang-Myeong;Kwon, Jae-Yong;Kang, Tae-Weon;Kim, Jeong-Hwan
    • Journal of electromagnetic engineering and science
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    • 제12권1호
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    • pp.63-69
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    • 2012
  • This paper presents the design of a calculable standard dipole antenna with a hybrid balun in the frequency range of 1 GHz to 3 GHz. A new formula of the antenna factor for a dipole antenna with a hybrid balun is derived using the power mismatch-loss concept. The antenna factors derived in this paper are in good agreement with the results calculated from S-parameters. The design results show that the calculable dipole antenna with a hybrid balun can be characterized by power mismatch-loss component factors.

Hybrid Model-Based Motion Recognition for Smartphone Users

  • Shin, Beomju;Kim, Chulki;Kim, Jae Hun;Lee, Seok;Kee, Changdon;Lee, Taikjin
    • ETRI Journal
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    • 제36권6호
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    • pp.1016-1022
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    • 2014
  • This paper presents a hybrid model solution for user motion recognition. The use of a single classifier in motion recognition models does not guarantee a high recognition rate. To enhance the motion recognition rate, a hybrid model consisting of decision trees and artificial neural networks is proposed. We define six user motions commonly performed in an indoor environment. To demonstrate the performance of the proposed model, we conduct a real field test with ten subjects (five males and five females). Experimental results show that the proposed model provides a more accurate recognition rate compared to that of other single classifiers.

자바리(Epinephelus moara ♀)와 대왕바리(E. lanceolatus ♂) 간 교잡종 대왕자바리의 형태 비교 (Comparison of Morphological Characteristics and Its Parent Species Hybrid Grouper between a Epinephelus moara ♀ and E. lanceolatus ♂)

  • 박종연;김용휘;방인철
    • 한국수산과학회지
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    • 제53권4호
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    • pp.572-576
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    • 2020
  • As grouper aquaculture production intensifies worldwide, hybrids are increasingly produced to induce heterosis of traits such as rapid growth and strong environmental adaptability. In this study, we compared the morphological characteristics of a hybrid grouper to those of its parent species Epinephelus moara and E. lanceolatus. The coefficients of external and skeletal traits evaluated using soft X-rays did not differ significantly among groups; however, several patterns were detected among measured traits. The body depth (BD), length of caudal peduncle (LCP), and pre-anal fin length (PAL) of the hybrid were the same as those of E. moara, whereas the pre-pectoral fin length (PPL) and interorbital width (IOW) of the hybrid were the same as those of E. lanceolatus. Traits that did not differ significantly among the three groups included pre-dorsal fin length (PDL), pre-ventral fin length (PVL), length of anal fin (LAF), and length of dorsal fin (LDF), whereas the depth of caudal peduncle (DCP) and snout length (SNL) showed intermediate traits, and eye diameter (ED) was significantly smaller in the hybrid. Therefore, intermediate traits such as DCP and SNL and specific traits such as ED may be used as indices for hybrid classification.