• Current Optics and Photonics
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• 제8권3호
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• pp.282-299
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• 2024

Target detection (TD) is a research hotspot in the field of hyperspectral imaging (HSI). Traditional TD methods often mine targets from HSIs under a single imaging condition, without considering the influence of imaging conditions. In fact, the spectra of ground objects in HSIs are uncertain and affected by the imaging conditions (weather, atmospheric, light, time, and other angle conditions including zenith angle). Hyperspectral data changes under different imaging conditions. Therefore, the detection result for a single imaging condition cannot accurately reflect the effectiveness of the detection method used. It is necessary to analyze the performance of various detection methods under different imaging conditions, to find a more applicable detection method. In this paper, we study the performance of TD methods under various land-based imaging conditions. We first summarize classical TD methods and evaluation methods. Then, the detection effects under various imaging conditions are analyzed. Finally, the concepts of the stability coefficient (SC) and effective area under the curve (EAUC) are proposed to comprehensively evaluate the applicability of detection methods under land-based imaging conditions, in terms of both detection accuracy and stability. This is conducive to our selection of detection methods with better applicability in land-based contexts, to improve detection accuracy and stability.

• 한국환경과학회지
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• 제3권1호
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• pp.31-38
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• 1994

The diffusion of the pollutants released into atmosphere is dependent on its chemical reaction, topography and micrometeorological characteristics. The purpose of the study is to investigate how much micrometeorological characteristics such as stability, wind speed and mixing height affect the diffusion of the air pollutants. For this purpose, this paper let 1) the basic theory be K-theory, 2) eddy diffusivity and wind speed be dependent on mixing height and stability, and 3) Grout method be used for numeric calculation. The result was 1) the more unstable condition, the higher mixing height and the higher wind speed we, the lower pollutants concentration appears, 2) the most intensive effect on the distribution of the pollutant concentration is the atmospheric stability.

• Journal of Microbiology and Biotechnology
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• 제4권1호
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• pp.1-6
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• 1994

Continuous culture was carried out with a recombinant Escherichia coli W3110/pCR185, which encodes trp-operon enzymes when the temperature is shifted from $37^{circ}C\;t;42^{\circ}C$. Under derepressed condition of $42^{\circ}C$. plasmlid stability and gene expression were analysed as function of the dilution rate. The stability of plasmid increased with the dilution rate, but maximal levels of gene expression (tryptophan concentration) and plasmid DNA content were obtained at the lowest dilution rate, $0.075\;hr^{-1}$. The plasmid instability, observed at low dilution rates, could be explained by the unbalanced biosynthetic state of the recombinant cell harboring a high copy number of plasmid.

• 한국응용과학기술학회지
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• 제23권4호
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• pp.362-367
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• 2006

This paper describes the experiments for investigating the effects of thermal stability of several commercial carpet mate materials. The melting point and thermal decomposition temperature was measured by means of a differential scanning calorimeter(DSC) in air condition. The DSC data and burning test results of nylon bulked continuous filament(N-BCF) yarn 100%, nylon(NY), polypropylene(PP), and a new material named polytrimethyleneterephthalate(PTT) were analysed to obtain the effect on their thermal stability. Conclusively, we observed that PTT and PP were approximately $380^{\circ}C$ and $240^{\circ}C$ to start the thermal decomposition, respectively. In other words, PTT is thermally the most stable material for carpet manufacturing.

• Transactions on Control, Automation and Systems Engineering
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• 제4권4호
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• pp.356-362
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• 2002

In this paper, well-known Takagi-Sugeno fuzzy model is used as the nonlinear plant model and uncertainty is assumed to be included in the model structure with known bounds. Based on the fuzzy models, a numerical robust stability analysis for the fuzzy feedback linearization regulator is presented using Linear Matrix Inequalities (LMI) Theory. For these structured uncertainty, the closed system can be cast into Lur'e system by simple transformation. From the LMI stability condition for Lur'e system, we can derive the robust stability condition for the fuzzy feedback linearization regulator based on Takagi-Sugeno fuzzy model. The effectiveness of the proposed analysis is illustrated by a simple example.

• 한국자동차공학회논문집
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• 제6권4호
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• pp.160-165
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• 1998

In this paper, We discuss the directional stability of a Mini-bus with varying suspension design parameters. We analyzed the vehicle behavior during the cornering in a transient steering condition. We made a vehicle model by use of DADS, which is dynamic analysis software, in order to carry out many cases of simulation with varying design parameters. The effect of toe-geometry change to vehicle stability is evaluated by computer simulation and the actual test. In order to reduce the under steer characteristics of a mini-bus, the amount of toe geometry change should be less than current value.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.465-472
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• 1999

Hydraulic model tests are performed to find economical and hdrqulically stable design of cooling water intake channel of steam power plant. The result of tests show that the standard distributiion of y-components in the chamber of CWP(circulating Water Pump) are recommended below 3.5 to maintain hydraulic stability, so that this value is considered as the design criteria. Common basin is necessary to improve the hydraulic stability of inflow, however the longer basin does not always improve the hydraulic stability , and the optimal length of basin can be found in some range. From the results the flow stability maintained the best condition when the length of basin is 7.2m. Beside the standard tests the auxiliary tests like edge , baffle, trapezoidal section and increase of pump capacity are carried out based on the optimal condition foudn in the standard tests. From the series of tests the economical and hydraulically stable design of intake channel was proposed.

• International Journal of Control, Automation, and Systems
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• 제2권4호
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• pp.501-508
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• 2004

A new method to solve a Lyapunov equation for a discrete delay system is proposed. Using this method, a Lyapunov equation can be solved from a simple linear equation and N-th power of a constant matrix, where N is the state delay. Combining a Lyapunov equation and frequency domain stability, a new stability condition is proposed for a discrete state delay system whose state delay is not exactly known but only known to lie in a certain interval.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2001년도 춘계학술대회 학술발표 논문집
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• pp.47-51
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• 2001

According as the controlled plants become more complex and large-scaled, the development of more intelligent control schemes is required in the control field. A fuzzy logic control (FLC) is one of proper schemes for this tendency. Recently, fuzzy control has been applied successfully to many industrial applications due to a number of advantages. But it still has some disadvantages. The conventional FLC has many tuning parameters: membership functions, scaling factors, and so forth. In order to improve this problem, a single-input fuzzy logic control (SFIC) which greatly simplifies the design process of the conventional FLC was proposed. Many research has also been proposed to develop the stability analysis of the FLC. In this paper we analyze the absolute stability of the SFLC. We first expand a nonlinear controlled plant into a Taylor series about a nominal operating point. And a fuzzy control system is transformed into a Lure system with nonlinearities. We also prove that the closed-loop system with the SFLC satisfies the sector condition globally.

• 전기학회논문지
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• 제61권12호
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• pp.1898-1902
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• 2012

In this paper, we consider the delay-dependent robust stability condition for polytopic uncertain systems with interval time-varying delay using various combinations of quantization and overflow nonlinearities. A robust stability condition for uncertain systems with time-varying delay and quantization/overflow nonlinearities is proposed by LMI(linear matrix inequality) and Lyapunov technique. It is shown that the proposed method is less conservative compared to the recent results by numerical examples.