• Structural Engineering and Mechanics
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• v.16 no.3
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• pp.327-340
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• 2003

Variations in system parameters due to uncertainties of parameters may result in system performance deterioration and create system internal stability problems. Uncertainties in structural modeling of structures are often considered to ensure that the control system is robust with respect to response errors. So the uncertain concept plays an important role in the analysis and design of the engineering structures. In this paper, the active control of the intelligent structures with the uncertainties is studied and a new method for analyzing the robustness of systems with the uncertainties is presented. Firstly, the system with uncertain parameters is considered as the perturbation of the system with deterministic parameters. Secondly, the feedback control law is designed on the basis of deterministic system. Thirdly, perturbation analysis and robustness analysis of intelligent structures with uncertainties are discussed when the feedback control law is applied to the original system and perturbed system. Combining the convex model of uncertainties with the finite element method, the analysis theory of the robustness of intelligent structures with the uncertainties can be developed. The description and computation of the robustness of intelligent structures with uncertain parameters is obtained. Finally, a numerical example of the application of the present method is given to show the validity of the method.

• Nuclear Engineering and Technology
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• v.52 no.7
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• pp.1443-1451
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• 2020

The objective of this study is to design a robust power control system for a small pressurized water reactor (PWR) to achieve stable power operations under conditions of external disturbances and internal model uncertainties. For this purpose, the multiple-input multiple-output transfer function models of the reactor core at five power levels are derived from point reactor kinetics equations and the Mann's thermodynamic model. Using the transfer function models, five local reactor power controllers are designed using an H infinity (H_∞) mixed sensitivity method to minimize the core power disturbance under various uncertainties at the five power levels, respectively. Then a multimodel approach with triangular membership functions is employed to integrate the five local controllers into a multimodel robust control system that is applicable for the entire power range. The performance of the robust power system is assessed against 10% of full power (FP) step load increase transients with coolant inlet temperature disturbances at different power levels and large-scope, rapid ramp load change transient. The simulation results show that the robust control system could maintain satisfactory control performance and good robustness of the reactor under external disturbances and internal model uncertainties, demonstrating the effective of the robust power control design.

• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.1
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• pp.217-225
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• 2003

Grouting internally with grout materials can repair the micro-cracks and micro-voids of construction joints more efficiently than injecting grouts from the surface of cracks. A new internal grouting method using perforated bundled-cables was developed in this study to enhance the structural integrity of the construction joints. The extensive experiments were performed to examine the mechanical behavior of construction joints which are repaired internally by the developed method. The tests were conducted for rectangular-shaped box wall structures and straight wall structures. The strength and permeability tests at grouted construction joints were conducted to evaluate the structural behavior of repaired construction joints. The present study indicates that the internal grouting method developed in this study enhances greatly the performance of construction joints and may be efficiently used for the leak-tight integrity of construction joints in concrete structures.

• Natural Product Sciences
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• v.22 no.1
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• pp.30-34
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• 2016

A simple and rapid method based on proton nuclear magnetic resonance spectroscopy was developed for determination of trans-anethole content in fennel essential oil. Spectra of pure trans-anethole, of the pure essential oil of fennel, and of the pure oil of fennel with thymol internal standard were recorded. The signal of $H-1^/$ was used for quantification of trans-anethole. This proton signal is well separated in the proton magnetic resonance spectrum of the compound. No reference compound is needed and cheap internal standard was used. The results obtained from spectroscopic analysis were compared with those obtained by gas chromatography. Additionally, the developed method was used for determination of the type of vegetable oil used as a carrier in commercial products, which cannot be quantified as such by gas chromatography. This study demonstrates the application of proton nuclear magnetic resonance spectroscopy as a quality control method for estimation of essential oil components.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.77.4-77
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• 2001

The quality of agricultural products is classified with various factors which are measured and determined by destructive and/or nondestructive method. NIR spectrum analysis method is used to determine internal qualities such as a brix and an acidity. CCD color camera is used to measure external quality like color and a size of fruit. today, nondestructive methods are widely researched. The quality and the garde of fruit loaded into a cup automatically and measured in real time by camera and NIR system is determined by internal and external factors. This paper proposes modified boundary tracking algorithm which detects the contour of fruit´s color image and make chain code faster than conventional method ...

• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.2
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• pp.135-140
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• 2003

As a construction technique is developed recently, the construction space and construction period are considered to important matters. Especially, in case of construction period, several method is proposed for strength control in the construction field. However there are very little strength control models for application of internal condition. The purpose of this study is to develop a strength control model for application of variety internal condition at construction field. The results are as follows ; 1) According to the results of compressive strength of concrete evaluated by logistic curve and proposed curve, proposed curve is applicable of construction field because there is similar relation with logistic curve. 2) It is shown that the construction period is shortened by reduction of the formwork removal time, because a predicted compressive strength of using the new curve is higher than the proposed compressive strength of standard.

• The Journal of Korean Medicine
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• v.20 no.2
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• pp.98-107
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• 1999

This study aimed to find out Oyo-Tang's effects on allergic asthma using the Egg-White Implant(EWI) method model recommended by Siqueira et al. Oyo-Tang has widely been prescribed and used in Oriental Medicine for controlling and curing of cough, nasal obstruction, pharyngeal pain and hoarseness. Previous studies have demonstrated that Oyo-Tang has analgesic, sedative, anticonvulsive, antitussive and antihistamine effects. But it was uncertain whether Oyo-Tang could inhibit the allergic reactions, to alleviate the symptoms of allergic asthma. With such aim. the respiratory patterns and eosinophil infiltration in the tracheal mucosa of rats with experimentally induced allergic asthma (using EWI method) were mainly observed. The results are as follows: 1. Oyo-Tang decreased the number of poor respiration with respect to control group (P<0.05) 2. Oyo-Tang decreased the number of eosinophils infiltrated in tracheal mucosa with respect control group (P<0.05). The above results demonstrate that Oyo-Tang has the inhibitory effects on the process allergic asthma and suggest that it could be used in relieving patients of the symptoms caused allergic asthma.

• Journal of Korea Water Resources Association
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• v.37 no.12
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• pp.1043-1054
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• 2004

An unsteady flow model for channel network including various internal boundaries if developed. It is a multiply-connected network model based on the Preissmann's four-point scheme and the Newton-Raphson method, where looped double-sweep algorithm is used. The model is capable of simulating flow through hydraulic structures such as dams and submerged weirs. It can also simulate automatic reservoir operation method (Auto ROM) for flood control, that is to maintain a target water level, by incorporating the strategy to the unsteady flow model as internal boundary condition. The model is applied to the Han River system that includes the downstream reaches of Choongju dam and Hwacheon dam as well as the downstream reach of the Paldang dam. Roughness coefficient for the downstream reach of Choongju dam is estimated. Automatic ROM is presumed for the Paldang, Chungpyung, Euiam, and Choonchun dams. The model is tested using historical flood records, and the flood control strategy is successfully simulated.

• Women's Health Nursing
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• v.3 no.2
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• pp.208-223
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• 1997

This study was made to suggest the nursing strategies for promoting the behaviors about bone mass health behaviors in order to prevent middle aged women's osteoporosis. This study was a descriptive-correlational design that also concerned to the types which improve bone mass promoting behaviors by inspecting patterns of health locus of control method out of recognizable variables of health improving models influencing on these bone mass promoting behaviors. For these purpose, data were collected by self reported questionnaire in middle school, from 158 women living in Seoul. The measuring tools used in this study about bone mass promoting behaviors and multidimensional health locus of control, were developed by author on the basis of literature review and analyzed by SPSS-PC window, into pearson's correlation, ANOVA, multiple regression, cluster analysis. Data was analyzed as follows. 1. 6 Multidimensional health locus of control scale clusters were existed. : a)cluster I (pure internal), b)cluster II(pure chance), c) cluster III(Believer in control), d), cluster IV(Type VI), e)cluster V(yea sayer), f) cluster VI(nay sayer). There were no findings of the powerful others external cluster and double external cluster. 2. The higher the value of internal health locus of control was, the better the bone mass promoting behaviors were(r=.2891, $p=.00^{**}$). The higher the value of chance external health locus of control was, the worse the bone mass promoting behaviors were(r=-.1367, $p=.00^{**}$). 3. On the basis of these relationships, 6 clusters were significantly different in the bone mass promoting behaviors(F=2.27, $p=.05^*$). The value of bone mass promoting behaviors was ranked the order of type VI>believer in control>pure internal>yea sayer>nay sayer>pure chance external highly. 4. Bone mass promoting behaviors were not significantly different as to age. Suggestion. Based on the results from the study, I would like to make some suggestions as follows. 1) To delay the loss of bone mass in middle aged women, the study on the cluster of the multidimensional health locus of control should be conducted repeatedly. 2) The tool of multidimensional health locus of control should be developed through a qualitative method adjusted on Korean' health culture.

• Tuberculosis and Respiratory Diseases
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• v.50 no.5
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• pp.615-623
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• 2001

Background : Pneumoconiosis is a parenchymal lung disease that results from the accumulation of coal dust in the lungs and the consequent tissue reaction. To evaluate the role of various personal factors in pneumoconiosis and the significance of some serologic markers for assessing the disease activity related to pneumoconiosis, the Rheumatoid Factor(RF), ${\alpha}_1$-AT, C-Reactive Protein(CRP), ceruloplasmin and fibrinogen levels were measured. Method : All the patients were males, 45-76 years old, and the mean duration of coal dust exposure was 23.2 years. 51 patients were classified as having Simple Pneumoconiosis (SP), 59 had Progressive Massive Fibrosis (PMF). Fifty eight men with ages ranging from 26-70 years were used as normal controls. The serum RF and CRP were titrated using an Autochemistry analyzer (HITACHI 7150 : Japan) and the ${\alpha}_1$-AT and ceruloplasmin levels were measured using a Nephelometer (Behring Nephelometer : Germany) and the fibrinogen levels were estimated by using an Autoanalyzer for hematologic coagulation. Result : There was a higher RF level in the SP, and PMF groups than in the control groups but there was no statistical difference. The CRP, ${\alpha}_1$-AT, and ceruloplasmin levels were also higher in the SP, and PMF groups. However, the fibrinogen concentration was within the normal ranges in both the SP and PMF groups. Conclusion : The CWP (Ed note : Define CWP) patients had significantly higher CRP, ${\alpha}_1$-AT, and ceruloplasmin levels compared to the control group. It is believed that these serologic changes could be used as a marker of the disease activity.