• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2003.11a
• /
• pp.361-365
• /
• 2003

In this paper, we proposed the effective serial connection methodology of PBG resonator with defect mode. We use the big difference of impedance ratio in connection region, for example dual PBG, for serial connection. This method reduces the PBG cells and is able to control the pole of bandpass filters. This result in flexibility in design of bandpass filter. Our PBG bandpass filter is modeled by using the ideal transmission line model. This model is very easy, fast, and effective for PBG structure.

• 한국정보통신설비학회:학술대회논문집
• /
• 2008.08a
• /
• pp.253-256
• /
• 2008

In this paper, we analyze the performance of RAKE receiver for impulse radio-ultra wide band (IR-UWB) systems in indoor multipath radio channel. Pulse position modulation-time hopping (PPM-TH) signal is considered. And we also consider three types of RAKE receivers, which are ideal RAKE, selective RAKE, and partial RAKE receivers. The indoor channel is modeled as the modified Saleh and Valenzuela (SV) model which has been proposed as a UWB channel model by the IEEE group, IEEE 802.15.SG3a.

• International conference on construction engineering and project management
• /
• 2009.05a
• /
• pp.323-330
• /
• 2009

This paper presents the selection, examination, and user test (SEUT) procedure to determine the ideal color scheme for a 4D model. This systematic procedure can be performed iteratively to obtain the color scheme that would be most appropriate for construction purposes. To verify the proposed procedure, an example case with two iterations is presented. Ten color schemes were examined and 48 users tested during the two iterations, and the result shows that the SEUT procedure is an effective method for determining the ideal color scheme for 4D models.

• Journal of Drive and Control
• /
• v.19 no.1
• /
• pp.51-61
• /
• 2022

This paper presents a model-free system based on a framework of a backstepping sliding mode control (BSMC) with a radial basis function neural network (RBFNN) and adaptive mechanism for electro-hydraulic systems (EHSs). First, an EHS mathematical model was dedicatedly derived to understand the system behavior. Based on the system structure, BSMC was employed to satisfy the output performance. Due to the highly nonlinear characteristics and the presence of parametric uncertainties, a model-free approximator based on an RBFNN was developed to compensate for the EHS dynamics, thus addressing the difficulty in the requirement of system information. Adaptive laws based on the actor-critic neural network (ACNN) were implemented to suppress the existing error in the approximation and satisfy system qualification. The stability of the closed-loop system was theoretically proven by the Lyapunov function. To evaluate the effectiveness of the proposed algorithm, proportional-integrated-derivative (PID) and improved PID with ACNN (ACPID), which are considered two complete model-free methods, and adaptive backstepping sliding mode control, considered an ideal model-based method with the same adaptive laws, were used as two benchmark control strategies in a comparative simulation. The simulated results validated the superiority of the proposed algorithm in achieving nearly the same performance as the ideal adaptive BSMC.

• 대한치과교정학회:학술대회논문집
• /
• 2004.11a
• /
• pp.32.2-32.2
• /
• 2004

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.53 no.4
• /
• pp.637-649
• /
• 2020

An ideal 3D primitive equation model is implemented to investigate upper ocean response to typhoons, focusing on rightward bias (RWB) which means an appearance of an intensified sea surface cooling to the right side of the typhoon track. The model has 26-stratified levels and a flat bottom (1000 m), covering a rectangular domain of about 3,060 km×3,300 km with four open boundaries. The sea water is forced by an atmospheric pressure and a gradient wind of the typhoon. The model well reproduces the RWB in previous observations and theoretical analyses. For the fast moving typhoon (FMT) (-8m/sec), the model shows that in the mixed layer (ML), the RWB in the SST noticeably appears clearly illustrating the coupling between inertial motion and wind stress, but in the subsurface layer (-100m), the RWB does not emerge since a cyclonic current field (CCF) caused by wind stress curl is primarily dominant. For the slowly moving typhoon (SMT) (-3m/sec), however, the RWB does not emerge because the coupling is weakened and the CCF is rather predominant even in the ML. In the model, we conclude that the RWB noticeably emerges in the FMT but does not emerge in the SMT related to predominance of CCF.

• Journal of the Daesoon Academy of Sciences
• /
• v.16
• /
• pp.105-130
• /
• 2003

Religious Though includes desirable attitudes towards existence of human beings and the value of life. These can be considered as the viewpoint of human being in religions. Also, the recognition frame of human being should be focused on the desirable human formation. That is, human being should not be viewed by already established frames, but human beings should be regarded as the ones that by themselves can build their true figures through developing human nature with the self-awareness of existence and the effort for establishing an ideal character. Without the correct concept of a 'human model', it is impossible to shed light on what the process of the human formation is and how the human formation willbe established. A 'human model', that is the goal of such a formation, might show different aspects if considering the historical situations including the circumstance of individuals and society. However, no matter how different 'human model', which are dependent upon phenomenal problems, are considered, it might most likely fails to grasp a fundamental issue without a 'human model' based on the essential problem of human being. In this regards, it can be considered that a 'Perfect person' with including both fundamental ways and relations of existence is the one enabling to establish a true 'human model' and, I try to show its striking example, 'Injon' that is an ideal 'human model' of Daesoon Thought. Therefore, this paper will show the interpretation and understanding of human beings in Daesoon Thought, and examine what their meanings are.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.4 no.4
• /
• pp.306-315
• /
• 1992

This paper addresses performance analysis of a reciprocating compressor. A computer simulation model has been developed to predict and estimate the compressor performance. Instead of using ideal gas equations, real gas equations are used in describing the state of gas. The compressor simulation model consists of a cylinder control volume, suction system and discharge system. Conservation laws of mass and energy are applied to the cylinder section only, The suction and discharge system are described by the Helmholtz resonator modeling. Some of input data required for the simulation have been obtained from experiments. These experimentally obtained input data are effective flow area, effective force area and dynamic characteristics of valves. Simulation results of real gas equations have been compared with those of ideal gas equations. It has been found that the simulation with real gas equations yields lower cylinder temperature and heat transfer compared with those of ideal gas equations. Differences in pressure, mass flowrates, valve motions and gas pulsations are found quite small.

• Proceedings of the Korean Society for Quality Management Conference
• /
• 1998.11a
• /
• pp.384-392
• /
• 1998

Dr. Taguchi proposed three models of ideal functions for dynamic systems with double signal factors. He also gave examples for each model yet without derivation. It will be difficult for other engineers to follow because Dr. Taguchi didn't show us how he obtained those models. Actually we can analyze each example from engineering aspect based on basic mechanism. In this paper we use brake systems to illustrate our approach of derivation and obtain a different form of ideal function from what Taguchi proposed. Our purpose is to provide an example that engineers can imitate and solve his problem at hand.

• 한국연소학회:학술대회논문집
• /
• 2012.11a
• /
• pp.89-91
• /
• 2012

The numerical simulation for detonation failure of ammonium nitrate (AN) based non-ideal explosives is carried out with an accurate and state-of-the-art Eulerian method. Detonation failure is readily observed in the rate stick experiments utilizing the AN mixture explosives and the inert confinements of varying thicknesses. The composition of non-ideal explosives and thickness of the confinements influence the characteristics of detonation failure. Calculated results are compared against the experimental data of both unconfined and confined rate stick problems and provide a reliable guideline to establish a fine-tuned chemical kinetic model for detonation failure.