• Korean Journal of Ichthyology
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• v.22 no.4
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• pp.225-229
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• 2010

A intergeneric hybrid between Rhodeus uyekii and Acheilognathus signifer was collected in the Jojongcheon Bukhan River. The hybrid showed intermediate characteristics of two parental types in some key characters, such as color pattern of body, pigmentation of dorsal, anal, and caudal fins, and body spot and stripe. In addition, the hybrid had a fairly large number of lateral line scales, while it lacked a barbel, which is known as a key intergeneric character. The probable occurrence of a natural hybrid is supported by a viable $F_1$ hybrid produced with the parental species.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.10a
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• pp.476-483
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• 2004

This paper presents a hybrid system combining lead rubber bearings and hydraulic actuators controlled by a μ-synthesis method for seismic response control of a cable-stayed bridge. A hybrid system could alleviate some of restrictions and limitations that exist when each system is acting alone because multiple control devices are operating. Therefore, the overall control performance of a hybrid system may be improved compared to each system, however the overall system robustness may be negatively impacted by active device in the hybrid system or active controller may cause instability due to small margins. Therefore, a f-synthesis method that guarantees the robust performance is considered to enhance the possibility of real applications of the control system. The control performances of the proposed control system are compared with those of passive, active, semiactive control systems and hybrid system controlled by LQG algorithm and an extensive robust analysis with respect to stiffness and mass matrices perturbation and time delay of actuator is performed. Numerical simulation results show that the control performance of the proposed control system is superior to that of the passive system and slightly better than that of the active and semiactive systems and two hybrid systems show similar control performances. Furthermore, the hybrid system controlled by a μ-synthesis method shows the good robustness without loss of control performances. Therefore, the proposed control system could effectively be used to seismically excited cable-stayed bridge which contains many uncertainties.

• Structural Engineering and Mechanics
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• v.5 no.4
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• pp.339-353
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• 1997

Fiber reinforced plastic (FRP) rods provide certain benefits over steel as concrete reinforcement, such as corrosion resistance, magnetic and electrical insulation, light weight, and high strength. FRP composites can be combined with a steel core to form hybrid reinforcing rods that take advantage of properties of both materials. The objective of this study was to characterize the bond behavior of hybrid FRP rods made with braided epoxy-impregnated aramid or poly-vinyl alcohol FRP skins. Eleven rod types were tested using two concrete strengths. Specific topics examined were bond strength, slip, and type of failure in concentric pull-out tests from concrete cubes. From analysis of identical pull-out tests on both hybrid and steel rods, information on relative bond strength and behavior were obtained. It is concluded that strength is similar but slip in hybrid rods is much higher. Hybrid rods failed either by pull-out or splitting the concrete block (with or without yielding of the steel core). Experimental data showed consistency with similar test results presented in the literature.

• Structural Engineering and Mechanics
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• v.36 no.3
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• pp.381-399
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• 2010

A fuzzy hybrid control technique using a semi-active tuned mass damper (STMD) has been proposed in this study for mitigation of wind induced motion of a tall building. For numerical simulation, a third generation benchmark is employed for a wind-excited 76-story building. A magnetorheological (MR) damper is used to compose an STMD. The proposed control technique employs a hierarchical structure consisting of two lower-level semi-active controllers (sub-controllers) and a higher-level fuzzy hybrid controller. Skyhook and groundhook control algorithms are used as sub-controllers. When a wind load is applied to the benchmark building, each sub-controller provides different control commands for the STMD. These control commands are appropriately combined by the fuzzy hybrid controller during realtime control. Results from numerical simulations demonstrate that the proposed fuzzy hybrid control technique can effectively reduce the STMD motion as well as building responses compared to the conventional hybrid controller. In addition, it is shown that the control performance of the STMD is superior to that of the sample TMD and comparable to an active TMD, but with a significant reduction in power consumption.

• Journal of information and communication convergence engineering
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• v.14 no.4
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• pp.246-251
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• 2016

In this study, we developed a reduced 94 GHz hybrid ring coupler on a GaAs substrate in order to demonstrate the possibility of the integration of various passive components and MMICs in the millimeter-wave range. To reduce the size of the hybrid ring coupler, we used multiple open stubs on the inside of the ring structure. The chip size of the reduced hybrid ring coupler with multiple open stubs was decreased by 62% compared with the area of the hybrid ring coupler without open stubs. Performance in terms of the loss, isolation, and phase difference characteristics exhibited no significant change after the use of the multiple open stubs on the inside of the ring structure. The reduced hybrid ring coupler showed excellent coupling loss of $3.87{\pm}0.33dB$ and transmission loss of $3.77{\pm}0.72dB$ in the measured frequency range of 90-100 GHz. The isolation and reflection were -48 dB and -32 dB at 94 GHz, respectively. The phase differences between two output ports were $180^{\circ}{\pm}1^{\circ}$ at 94 GHz.

• Korean Journal of Materials Research
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• v.30 no.3
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• pp.111-116
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• 2020

Two different casting speeds of 60 and 80mm/min are adopted to determine the effect of casting speed on the microstructure and mechanical properties of Al-Mg-Si/Al hybrid material prepared by duo-casting. The obtained hybrid material has a uniform and straight macro-interface between the pure Al side and the Al-Mg-Si alloy side at both casting speeds. When the casting speed is increased to 80mm/min, the size of primary α phases in Al-Mg-Si alloy decreases, without change of shape. Although the Al-Mg-Si alloy produced at higher casting speed of 80mm/min shows much higher ultimate tensile strength (UTS) and 0.2 % proof stress and lower elongation, along with higher bending strength compared to the case of the 60mm/min in casting speed, the tensile properties and bending strength of the hybrid material, which are similar to those of pure Al, are the same regardless of the increase of casting speed. Despite the different casting speeds, deformation and fracturing in hybrid materials are observed only on the pure Al side. This indicates that the macro-interface is well-bonded, allowing it to endure tensile and bending deformation in all hybrid materials.

• Macromolecular Research
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• v.15 no.5
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• pp.449-458
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• 2007

The aims of this study were to investigate the intercalation of polymer chains with organoclays and improve the thermo-mechanical properties of poly(butylene terephthalate) (PBT) hybrids by comparing PBT hybrids synthesized using two different organoclays. The organoclays; dodecyltriphenylphosphonium-montmorillonite ($C_{12}PPh-MMT$) and dodecyltriphenylphosphonium-mica ($C_{12}PPh-Mica$), were used to fabricate the PBT hybrid fibers. Variations in the properties of the hybrid fibers with the organoclays within the polymer matrix, as well as the draw ratio (DR), are discussed. The thermo-mechanical properties and morphologies of the PBT hybrid fibers were characterized using differential scanning calorimetry, thermogravimetric analysis, wide-angle X-ray diffraction, electron microscopy and mechanical tensile properties analysis. The nanostructures of the hybrid fibers were determined using both scanning and transmission electron microscopies, which showed some of the clay layers to be well dispersed within the matrix polymer, although some clustered or agglomerated particles were also detected. The thermal properties of the hybrid fibers were found to be better than those of the pure PBT fibers at a DR = 1. The tensile mechanical properties of the $C_{12}PPh-MMT$ hybrid fibers were found to worsen with increasing DR. However, the initial moduli of the $C_{12}PPh-Mica$ hybrid fibers were found to slightly increase on increasing the DR from 1 to 18.

• Korean Journal of Metals and Materials
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• v.50 no.10
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• pp.729-734
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• 2012

This study investigated the effect of water absorption on the tensile properties of carbon-glass/epoxy hybrid composites at room temperature and $-30^{\circ}C$. To investigate the effect of the position of glass fabric in the hybrid composite on the tensile properties, the stacking pattern of the fiber fabrics for reinforcing was created in three different ways: (a) glass fabrics sandwiched between carbon fabrics, (b) carbon fabrics sandwiched between glass fabrics and (c) alternative layers of carbon and glass fabrics. They were manufactured by a vacuum-assisted resin transfer molding (VARTM) process. The results showed that there was surprisingly little difference in tensile strength at the two different temperatures with dry and wet conditions. However, the water absorption into the hybrid system affected the tensile properties of the hybrid composites at RT and $-30^{\circ}C$. When the glass fabrics were at the outermost layers, the hybrid composite had the lowest tensile properties. This is attributed to the fact that the composite had a relatively high water absorption rate.

• Journal of the Semiconductor & Display Technology
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• v.21 no.1
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• pp.142-147
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• 2022

After introducing Hybrid Bonding technology into image sensors using stacked sensors and image processors, large quantity production became possible. As a result, it is currently used in most of the CMOS image market in smartphones and other image-based devices worldwide, and almost all stacked CIS manufacturing sites have focused on miniaturization using hybrid bonding. In this study, an upper wafer handling module for Wafer to Wafer Hybrid Bonding developed to increase the alignment and precision between wafers when wafer bonding. The module was divided two parts to reduce error of both the alignment and degree of precision during wafer bonding. Wafer handling module developed both new Tip/Tilt system controlling θx,θy of upper wafer and striker to push upper wafer. Based on this, it was confirmed through the stability evaluation that the upper wafer handling module can be controlled without any problem during W2W hybrid bonding.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.5
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• pp.613-619
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• 2005

Indigenous Yakutian cattle' adaptation to the hardest subarctic conditions makes them a valuable genetic resource for cattle breeding in the Siberian area. Since early last century, crossbreeding between native Yakutian cattle and imported Simmental and Kholmogory breeds has been widely adopted. In this study, variations at 22 polymorphic microsatellite loci in 5 populations of Yakutian, Kholmogory, Simmental, Yakutian-Kholmogory and Yakutian-Simmental cattle were analysed to estimate the genetic contribution of Yakutian cattle to the two hybrid populations. Three statistical approaches were used: the weighted least-squares (WLS) method which considers all allele frequencies; a recently developed implementation of a Markov chain Monte Carlo (MCMC) method called likelihood-based estimation of admixture (LEA); and a model-based Bayesian admixture analysis method (STRUCTURE). At population-level admixture analyses, the estimate based on the LEA was consistent with that obtained by the WLS method. Both methods showed that the genetic contribution of the indigenous Yakutian cattle in Yakutian-Kholmogory was small (9.6% by the LEA and 14.2% by the WLS method). In the Yakutian-Simmental population, the genetic contribution of the indigenous Yakutian cattle was considerably higher (62.8% by the LEA and 56.9% by the WLS method). Individual-level admixture analyses using STRUCTURE proved to be more informative than the multidimensional scaling analysis (MDSA) based on individual-based genetic distances. Of the 9 Yakutian-Simmental animals studied, 8 showed admixed origin, whereas of the 14 studied Yakutian-Kholmogory animals only 2 showed Yakutian ancestry (>5%). The mean posterior distributions of individual admixture coefficient (q) varied greatly among the samples in both hybrid populations. This study revealed a minor existing contribution of the Yakutian cattle in the Yakutian-Kholmogory hybrid population, but in the Yakutian-Simmental hybrid population, a major genetic contribution of the Yakutian cattle was seen. The results reflect the different crossbreeding patterns used in the development of the two hybrid populations. Additionally, molecular evidence for differences among individual admixture proportions was seen in both hybrid populations, resulting from the stochastic process in crossing over generations.