• Journal of the Korean Institute of Landscape Architecture
• /
• v.13 no.2
• /
• pp.27-36
• /
• 1985

^x In Korea, we are entering on a new phase that the use concept of urban park is extending to dynamic activities such as games and sports. This article is to investigate the significance of lawn areas, as a receptive space of such a wide range of recreation activities. As a study process, Green Styles (type of parks) such as Garden Type, Park Type and Forest Type were studied and historical review of lawn areas in park development was performed. In conclusion, the lawn areas ( greensward) are an essential part of park and open space organization. The significance as a conclusion is presented as follows : 1 ) Balance in type of parks The structures of our parks and open spaces are inclined toward the artificial Garden Type and natural Forest Type. Therefore, the intermediate Park Type and sparse wood areas should be a core part of our park and open space development. 2) Psychological effect Park Type areas, thorned by greensward(lawn area), can refresh urban dwellers with natural picturesque landscaps, and Park Type landscape is the most preferred natural landscape. It shows the essence of natural amenity as 3) Accomodation of wide range of recreation activities Lawn areas in urban park are the best place in accomodating the wide range of active and massive recreation activities. Thus, lawn areas can increase the freedom of recreation use in urban park. 4) Enlargement of physical carrying capacity. With expansion of lawn areas of euro- american concept, the structural open space can be transformed into service open space. Thus, the recreation carrying capacity of urban parks can be enlarged.

• Proceedings of the IEEK Conference
• /
• 2003.07a
• /
• pp.621-624
• /
• 2003

In this paper, two Cascode Low Noise Variable Gain Amplifiers are proposed for wide dynamic range and constant Noise Figure for frequency range of 2.4GHz. Designed Variable Gain Low Noise Amplifier are for Wireless Local Area Network (WLAN) applications. A gain is higher than 17dB and the noise figure is approximately 1.3dB and the input VSWR is better than 2:1.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.9 no.6
• /
• pp.428-434
• /
• 2004

Coarse clumping of solid materials within diseased biological cells can have a marked influence on the light scattering pattern. Perturbations in refractive index lead to distinct varia­tions in the cytometric signature, especially apparent over wide scattering angles. The large dynamic range of scattering intensities restricts collection of data to narrow angular intervals be­lieved to have the highest potential for medical diagnosis. We propose the use of an interfer­ence filter to reduce the dynamic range. Selective attenuation of scattering intensity levels is expected to allow simultaneous data collection over a wide angular interval. The calculated angu­lar transmittance of a commercial shortwave-pass filter of cut-off wavelength 580 nm indicates significant attenuation of scattering peaks below ${\~}\;10^{circ}$, and reasonable peak equalization at higher angles. For the three-dimensional calculation of laser light scattered by cells we use a spectral method code that models cells as spatially varying dielectrics, stationary in time. How­ever, we perform preliminary experimental testing with the interference filter on polystyrene microspheres instead of biological cells. A microfluidic toolkit is used for the manipulation of the microspheres. The paper intends to illustrate the principle of a light scattering detection system incorporating an interference filter for selective attenuation of scattering peaks.

• KIEAE Journal
• /
• v.12 no.4
• /
• pp.97-104
• /
• 2012

A phase-change material is a substance with a high heat of fusion which, melting and freezing at a certain temperature, is capable of storing and releasing large amounts of energy. Heat is absorbed or released when the material changes from solid to liquid. Therefore, PCMs are classified as latent heat storage (LHS) units. The purpose of this study is to analyze PCM wallboard design parameters using dynamic energy simulation. Among the factors of PCM, melting temperature, latent heat, phase change range, thermal conductivity are very important element to maximize thermal energy storage. In order to analyze these factors, EnergyPlus which is building energy simulation provided by department of energy from the U.S is used. heat balance algorithm of energy simulation is conduction finite difference and enthalpy-temperature function is used for analyzing latent heat of PCM. The results show that in the case of melting temperature, the thermal energy storage could be improved when the melting temperature is equal to indoor surface temperature. It seems that when the phase change range is wide, PCM can store heat at a wide temperature, but the performance of heat storage is languished.

• The Korean Journal of Physiology and Pharmacology
• /
• v.2 no.2
• /
• pp.155-163
• /
• 1998

The purpose of present study was to compare the effects of somatostatin (SOM) and morphine (Mor) on the responses of wide dynamic range (WDR) cells to peripheral noxious stimulation. Single neuronal activity was recorded with a carbon-filament electrode at the lumbosacral enlargement of cat spinal cord. After identifying WDR cells, their responses to peripheral noxious mechanical or thermal stimuli were characterized and the effects of SOM and Mor, applied either iontophoretically or intrathecally, were studied. In most cells SOM and Mor suppressed noxious stimulus-evoked WDR neuronal activity, though a few WDR neurons showed no change or were excited by SOM and Mor. Systemically applied naloxone, a non-specific opioid antagonist, always reversed the Mor induced suppression of neuronal activity evoked by noxious mechanical stimuli, but did not always reverse the suppression of neuronal activity elicited by SOM. The suppressive effect of Mor on thermal stimulus-evoked neuronal activity was partially reversed by naloxone, while that of SOM were not reversed at all. The above results suggest that both Mor and SOM exert an inhibitory effect on thermal and mechanical stimulus-evoked WDR neuronal activity in cat spinal dorsal horn, but the mechanisms are dependent upon the functional populations of dorsal horn nociceptive neurons.

• Progress in Superconductivity
• /
• v.5 no.1
• /
• pp.31-37
• /
• 2003

Wide-bandwidth SQUID current amplifier and its control electronics have been constructed for detecting pulse outputs of a superconducting microcalorimeter. The current amplifier made of a double relaxation oscillation SQUID (DROS) has a bandwidth of 1.2 MHz and typical white noise level of about 6 pA/(equation omitted) Hz. To increase the dynamic range of the current amplifier, the flux-locked loop (FLL) has additional circuits to reset the integrator and to count reset numbers which present the number of passed flux quanta. In this system, dynamic range covers from -65 mA to +65 mA. SQUID electronics are controlled by software to get the optimum FLL condition, and to control the current to bias the transition edge sensor (TES). The electronics are shielded from the outside electromagnetic noises by using an aluminum case of 66 mm ${\times}$ 25 mm ${\times}$ 100 mm, and consist of 2 separate printed-circuit-boards for the current amplifier and the control electronics, respectively. The SQUID current amplifier and its control electronics will be used in TESs for detecting photons such as UV and X-ray with high energy resolution.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.25 no.7
• /
• pp.15-25
• /
• 2011

This proposes an online loss minimization algorithm for series PI(SPI) based interior permanent magnet synchronous motor(IPMSM) drive to yield high efficiency and high dynamic performance over wide speed range. The loss minimization algorithm is developed based on the motor model. In order to minimize the controllable electrical losses of the motor and thereby maximize the operating efficiency, the d-axis armature current is controlled optimally according to the operating speed and load conditions. For vector control purpose, a SPI is used as a speed controller which enables the utilization of the reluctance torque to achieve high dynamic performance as well as to operate the motor over a wide speed range. Also, this paper proposes current control of model reference adaptive fuzzy controller(MFC), and estimation of speed using artificial neural network(ANN) controller. The proposed efficiency optimization control, SPI, MFC, ANN in this paper is applied to IPMSM drive system, the validity of this paper is proved by analyzing response characteristics in variety operating conditions.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.49 no.10
• /
• pp.142-147
• /
• 2012

This paper presents a mixed-mode CMOS duty-cycle corrector (DCC) circuit that has a dynamic frequency scaling (DFS) counter and coarse and fine tuning adjustments. A higher duty-cycle correction accuracy and smaller jitter have been achieved by utilizing the DFS counter that reduces the bit-switching glitch effect of a digital to analog converter (DAC). The proposed circuit has been designed using a 0.18-${\mu}m$ CMOS process. The measured duty cycle error is less than ${\pm}1.1%$ for a wide input duty-cycle range of 25-75% over a wide freqeuncy range of 0.5-1.5 GHz.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2010.07a
• /
• pp.203-207
• /
• 2010

In this paper, The design and implementation of Multi Channel Receiver is described in this paper. This Receiver system operates at X-band with processing received signal, more than 80[dB] dynamic range and wide-band signals at the same time. To process direct received signals, this system has the built-in Digital De-modulators which offer the minimum loss on the receiving signal pass and has high stability by adding Built-In Test (BIT). The performance of Multi Receiver is the following. The gain, noise figure, difference of amplitude and phase on the signal pass is respectively $14{\pm}2[dB]$, 19[dB], ${\pm}2[dB]$, and $10^{\circ}$ below.

• Journal of Power Electronics
• /
• v.15 no.6
• /
• pp.1577-1583
• /
• 2015

In this research, a combined adaptive-robust current controller is developed for non-minimum-phase DC-DC converters in a wide range of operations. In the proposed nonlinear controller, load resistance, input voltage and zero interval of the inductor current are estimated using developed adaptation rules and knowing the operating mode of the converter for the closed-loop control is not required; hence, a single controller can be employed for a wide load and line changes in discontinuous and continuous conduction operations. Using the TMS320F2810 digital signal processor, the experimental response of the proposed controller is presented in different operating points of the buck/boost converter. During transition between different modes of the converter, the developed controller has a better dynamic response compared with previously reported adaptive nonlinear approach. Moreover, output voltage steady-state error is zero in different conditions.