• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.450-450
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• 2000

This paper presents a software design simulation method for controlling multiple mechanism carrier system (MMCS), which is mainly used in a wrapping machine or a case packing machine. This method uses a mechanical tool-work interactive model proposed in this paper, in order to represent the interactive behaviors between some tools and a work driven by their tools, in which low effect states of a work are defined. Based on this method, a 3-D simulation system has been built. It consists of shape modeling of each device, behavior definitions of tools, and control logic using if-then expression. By applying it to a ase packing machine having about 30 mechanical devices and 100 inputs/outputs for control, the effectiveness of this method has been shown in general verification of control logic specification in an early software design phase and the possibility of smooth communication tool between mechanical and software designers.

• Applied Science and Convergence Technology
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• v.23 no.4
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• pp.161-168
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• 2014

A real-time monitoring of immersed antenna type inductively coupled plasma (ICP) was done with a homemade 2 dimensional voltage probe array to check the uniformity of the plasma. Measured voltage values with a high impedance voltmeter are close to the floating potential of the plasma. As the substrate carrier was moving into a magnetron sputtering plasma diffusive from a $125mm{\times}625mm$ size cathode, measured results showed reliably separation of plasma into the upper and lower empty space over the carrier. Infra red thermal imaging camera was used to observe the cross corner effect in situ without eroding a target to the end of the usage. 3 dimensional particle trace model was used to analyze the magnetron discharge's behavior.

• Journal of Korea Society of Digital Industry and Information Management
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• v.16 no.1
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• pp.93-98
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• 2020

Research on underwater sensor networks is increasing due to such reasons as marine resource management, maritime disaster prediction and military protection. Many underwater sensor networks performs wireless communication using an acoustic sound wave band signal having a relatively low frequency. So the digital part of their modem can take charge of carrier band signal processing. To enable this, the sampling rate of the baseband band signal should be increased to a sampling rate at which carrier band signal processing is possible. In this paper, we designed a sampling rate increasing circuit based on a CIC interpolator for underwater sensor nodes. The CIC interpolator has a simple circuit structure. However, since the CIC interpolator has a large attenuation of the pass band and a wide transition band, an inverse sinc LPF is added to compensate for frequency response of the CIC interpolator. The proposed interpolator was verified in time domain and frequency domain using ModelSim and Matlab.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1997.11a
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• pp.451-462
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• 1997

A 2-dimensional numerical analysis is presented for thermal-electron heat conduction effects upon the electron transport and the drain current-voltage characteristics of submicron GaAs MESFETs, based on the use of a nonstationary hydrodynamic transport model. It is shown that for submicron GaAs MESFETs, electron heat conduction effects are significant on their internal electronic properties and also drain current-voltage characteristics. Due to electron heat conduction effects, the electron energy is greatly one-djmensionalized over the entire device region. Also, the drain current decreases continuously with increasing thermal conductivity in the saturation region of large drain voltages above 1 V. However, the opposite trend is observed in the linear region of small drain voltages below 1 V. Accordingly, for a large thermal conductivity, negative differential resistance drain current characteristics are observed with a pronounced peak of current at the drain voltage of 1 V. On the contrary, for zero thermal conductivity, a Gunn oscillation characteristic is observed at drain voltages above 2 V under a zero gate bias condition.

• Journal of electromagnetic engineering and science
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• v.10 no.4
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• pp.322-327
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• 2010

Spaceborne sparse array radar for ground moving targets indication (GMTI) has outstanding advantage over full array radar for constructing ultra-large aperture. Rapid development of millimeter wave (MMW) technology make it possible for realizing MMW GMTI radar, which is much more sensitive to slow moving ground target. The paper presented the system model of a multi-carrier frequency sparse array MMW radar as well as preliminary simulation results, which showed future application of the system is very promising.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.754-756
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• 1987

In this paper, a new Harmonic Torque Factor(HTF) that represents torque ripple of induction motor is proposed. Trapezoidal PWM is analyzed to torque ripple by HTF and than we obtain optimum triangular factor at some carrier ratio. Six-step, sinusoidal PWM and Trapezoidal PWM are compared and evaluated for choosing a good control strategy of PWM inverter. It turns out that six-step inverter is better than sinusoidal PWM and Trapezoidal PWM when their carrier ratio is 9, and Trapezoidal PWM is superior to sinusoidal PWM. At induction motor is driven by PWM inverter, torque ripples are investigated by computer simulation using d-q two axis model. It is proved that a new Harmonic Torque Factor ix valid.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1159-1161
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• 1993

This paper may be presented the carrier oscillation properties for the varistor fabricated by a new method of three-composition seed grain, in order to analyze the behavior of carriers at the its equivalent circuit model. The oscillation phenomena of carriers appeared from current-voltage characteristics under knee voltage is shown by the transient flow of non trapped carriers group in the trap level of intergranular layer, surface state and/or depletion layer. However, Current oscillation phenomena is hardly shown in the high electric field. The injected carriers from both electrodes are directly flowed from the conduction band of forward biased grain through the intergranular layer into the reverse biased grain, because the trap level in the electric field above the knee voltage is mostly filled.

• Bulletin of the Korean Chemical Society
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• v.22 no.11
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• pp.1243-1247
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• 2001

The water-soluble poly(aminoaryloxy-methylamino phosphazene) has been synthesized and investigated as a polymeric carrier species for the covalent attachment of biologically active agents. The cyclic trimeric model systems were utilized for the synthesis of polymeric analogues containing bioactive side groups. The sodium salt of 4-acetamidophenol was first allowed to react with (NPCl2)3 or (NPCl2)n and was then treated with excess methylamine to yield derivatives of type [NP(NHCH3)x(OArNHCOCH3)y]3 or [NP(NHCH3)x(OArNHCOCH3)y]n. The 4-acetamido groups were then hydrolyzed to 4-aminophenoxy units with potassium tert-butoxide. Coupling reactions between amino group and N-acetylglycine was accomplished with the use of dicyclohexylcarbodiimide. Their properties and structural characterization are discussed.

• YAKHAK HOEJI
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• v.27 no.1
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• pp.21-28
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• 1983

Distribution volume (Vd$_{ss}$ ) of a model basic drug, tetraethylammonium bromide (TEA) at a steady-state decreased sinificantly in glycerol and uranium-renal failure rats. Assuming carrier-mediated transport of TEA into tissues, the theoretical $Vd_{ss}$ of TEA decreases in an exponential way as the plasmal concentration of TEA increases. The relationship between $Vd_{ss}$ and plasma concentration of TEA in the experimental renal failure (ERF)-rats was similar. Therefore, the decrease in $Vd_{ss}$ of TEA in the ERF-rats seemed to be due to the saturation of the carrier system that are responsible for the tissue distribution of TEA, by the elevated plasma concentration of TEA in the ERF-rats. ERF was induced to rats with glycerol, folate, salicylate, uranium and gentamicin, respectively..

• International Journal of Computer Science & Network Security
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• v.24 no.2
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• pp.95-100
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• 2024

Cyclic Delay Diversity (CDD) is a diversity scheme used in OFDM-based telecommunication systems, transforming spatial diversity into frequency diversity and thus avoiding intersymbol interference without entailing the receiver to be aware of the transmission strategy making the signal more reliable achieving full diversity gain in cooperative systems. Here the analyzation of the influence of CDD-SC scheme in Cognitive Radio Network (CRN) is done with the challenge of overcoming the complication called channel estimation along with overhead in CNR. More specifically, the closed-form expressions for outage probability and symbol error rate are divided under different frequencies among independent and identically distributed (i.i.d.) frequency selective fading channel model i.e., the signal is divided into different frequencies and transmitted among several narrow band channels of different characteristics. It is useful in the reduction of interference and crosstalk. The results reveal the diversity order of the proposed system to be mainly affected by the number of multipath components that are available in the CNR.