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Model algorithm control using neural networks for input delayed nonlinear control system

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Journal of Systems Engineering and Electronics 2015年第1期26卷 142-150页

作者： Yuanliang Zhang kil To Chong School of Mechanical Engineering Huaihai Institute of Technology School of Electronics and Information Chonbuk National University

The performance of the model algorithm control method is partially based on the accuracy of the system＇s model. It is difficult to obtain a good model of a nonlinear system, especially when the nonlinearity is high. Neural networks have the ability to ＂learn＂the characteristics of a system through nonlinear mapping to represent nonlinear functions as well as their inverse functions. This paper presents a model algorithm control method using neural networks for nonlinear time delay systems. Two neural networks are used in the control scheme. One neural network is trained as the model of the nonlinear time delay system, and the other one produces the control inputs. The neural networks are combined with the model algorithm control method to control the nonlinear time delay systems. Three examples are used to illustrate the proposed control method. The simulation results show that the proposed control method has a good control performance for nonlinear time delay systems.

关键词： model algorithm control neural network nonlinear system time delay

Adaptive network fuzzy inference system based navigation controller for mobile robotAdaptive network fuzzy inference system based navigation controller for mobile robot

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Frontiers of Information Technology & Electronic Engineering 2019年第2期20卷 141-151页

作者： Panati SUBBASh kil To ChONG Department of Electronics and Information Engineering Chonbuk National University Advanced Electronics and Information Research Center Chonbuk National University

Autonomous navigation of a mobile robot in an unknown environment with highly cluttered obstacles is a fundamental issue in mobile robotics research. we propose an adaptive network fuzzy inference system(ANFIS) based navigation controller for a differential drive mobile robot in an unknown environment with cluttered obstacles. Ultrasonic sensors are used to capture the environmental information around the mobile robot. A training data set required to train the ANFIS controller has been obtained by designing a fuzzy logic based navigation controller. Additive white Gaussian noise has been added to the sensor readings and fed to the trained ANFIS controller during mobile robot navigation, to account for the effect of environmental noise on sensor readings. The robustness of the proposed navigation controller has been evaluated by navigating the mobile robot in three different environments. The performance of the proposed controller has been verified by comparing the travelled path length/efficiency and bending energy obtained by the proposed method with reference mobile robot navigation controllers, such as neural network, fuzzy logic, and ANFIS. Simulation results presented in this paper show that the proposed controller has better performance compared with reference controllers and can successfully navigate in different environments without any collision with obstacles.

关键词： Adaptive network fuzzy inference system Additive white Gaussian noise Autonomous navigation Mobile robot

Stability Problem for Jensen-type Functional Equations of Cubic Mappings

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Acta Mathematica Sinica,English Series 2006年第6期22卷 1781-1788页

作者： kil-woungJUN hark-MahnKIM Department of Mathematics Chungnam National University

In this paper, we establish the general solution and the generalized hyers-Ulam-Rassias stability problem for a cubic Jensen-type functional equation,4f（（3x＋y）/4）＋4f（（x＋3y）/4）=6f（（x＋y）/2）＋f（x）＋f（y）,9f（（2x＋y/3）＋9f（（x＋2y）/3）=16f（（x＋y）/2＋f（x）＋f（y）in the spirit of D. h. hyers, S. M. Ulam, Th. M. Rassias and P. Gaevruta.

关键词： Jensen equation hyers-Ulam-Rassias stability cubic mapping

Machine Learning-Based Predictions on the Self-heating Characteristics of Nanocomposites with hybrid Fillers

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Computers, Materials & Continua 2022年第6期71卷 4487-4502页

作者： Taegeon kil D.I.Jang h.N.Yoon Beomjoo Yang Department of Civil and Environmental Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon34141Korea School of Civil Engineering Chungbuk National UniversityCheongju28644Korea

A machine learning-based prediction of the self-heating characteristics and the negative temperature coefficient(NTC)effect detection of nanocomposites incorporating carbon nanotube(CNT)and carbon fiber(CF)is *** CNT content was fixed at 4.0 wt.%,and CFs having three different lengths(0.1,3 and 6 mm)at dosage of 1.0 wt.%were added to fabricate the *** self-heating properties of the specimens were evaluated via self-heating *** on the experiment results,two types of artificial neural network(ANN)models were constructed to predict the surface temperature and electrical resistance,and to detect a severe NTC *** present predictions were compared with experimental values to verify the applicability of the proposed ANN *** ANN model for data prediction was able to predict the surface temperature and electrical resistance closely,with corresponding R-squared value of 0.91 and 0.97,*** ANN model for data detection could detect the severe NTC effect occurred in the nanocomposites under the self-heating condition,as evidenced by the accuracy and sensitivity values exceeding 0.7 in all criteria.

关键词： Machine learning nanocomposites carbon fillers self-heating negative temperature coefficient

Infrageneric relationships of Korean Viola based on eight chloroplast markers

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Journal of Systematics and Evolution 2010年第6期48卷 474-481页

作者： Ki-Oug YOO Su-kil JANG Department of Biological Sciences Kangwon National University

Phylogeny and infrageneric relationships were reconstructed for Korean Viola(Violaceae) using eight chloroplast sequences:the atpB-rbcL intergenic spacer,the atpF-h intergenic spacer,the matK gene,the psbA-trnh intergenic spacer,the psbK-I intergenic spacer,the rpl16 intron,the rpoC1 exon 2,and the trnL-trnF *** combined analyses of the eight chloroplast regions suggest that sections Dischidium and Chamaemelanium are monophyletic,whereas section Nomimium is paraphyletic;sections Dischidium and Chamaemelanium form a clade with subsections hypocarpae and Trigonocarpae of section Nomimium,but unresolved within the clade;two subsections(*** and Vaginatae) of section Nomimium form a clade and are placed between the stem and stemless species group;and subsection Patellares of section Nomimium is monophyletic,and Viola dissecta is diverged first in the clade with high support(BS = 100,PP = 100).Our present results support the subsectional grouping based on morphological characteristics,although discordance remained at the series level.

关键词： chloroplast DNA infrageneric relationships phylogeny series subsection Viola.

Development of Ubiquitous Simulation Service Structure Based on high Performance Computing Technologies

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Journal of Materials Science & Technology 2008年第3期24卷 374-378页

作者： Sang-hyun ChO Jeong-kil ChOI Center For e-Design KITECH7-47Songdo-DongYeonsu-Ku

The simulation field became essential in designing or developing new casting products and in improving manufacturing processes within limited time, because it can help us to simulate the nature of processing, so that developers can make ideal casting designs. To take the prior occupation at commercial simulation market, so many development groups in the world are doing their every effort. They already reported successful stories in manufacturing fields by developing and providing the high performance simulation technologies for multipurpose. But they all run at powerful desk-side computers by well-trained experts mainly, so that it is hard to diffuse the scientific designing concept to newcomers in casting field. To overcome upcoming problems in scientific casting designs, we utilized information technologies and full-matured hardware backbones to spread out the effective and scientific casting design mind, and they all were integrated into Simulation Portal on the web. It professes scientific casting design on the NET including ubiquitous access way represented by ＂Anyone, Anytime, Anywhere＂ concept for casting designs.

关键词： Parallel computation Message passing interface (MPI) Shared memory processing (SMP) Clustering Ubiquitous

Changes in Reverse Cardiac Remodeling after Percutaneous Atrial Septal Defect Closure in Children and Adults

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Congenital heart Disease 2021年第3期16卷 211-220页

作者： Geena Kim hong Ryang kil Department of Pediatrics Chungnam National University Sejong HospitalChungnam National University School of MedicineSejong30099Korea Department of Pediatrics Chungnam National University HospitalChungnam National University School of MedicineDaejeon35105Korea

Background:The influence of the timing of transcatheter atrial septal defect(ASD)closure on ventricular remodeling at 6 months after ASD closure is *** study investigated changes in cardiac remodeling after transcatheter closure of large ASDs according to patient age at the time of the ***:In this study,41 children and 43 adults underwent percutaneous closure of a large *** remodeling was assessed by two-dimensional echocardiography and electrocardiography before and at 6 months after ASD ***:The age of the children and adults were 2.8±3.1 and 50.0±15.6 years,*** Qp/Qs ratio of all patients was 2.24±*** right atrial(RA)maximal dimension and right ventricular(RV)transverse diameter were significantly decreased and the left ventricular(LV)dimension was significantly increased at 6 months after ASD ***,the difference in RA and RV dimension changes between the groups was not statistically *** difference in left atrial(LA)dimension changes between the groups was also not statistically significant,but the LV dimension significantly increased in children compared with that in adults(P=0.018).The RV/LV ratio was decreased after ASD closure,and a significant difference was found in the RV/LV ratio changes between the *** ECG,the PR interval was significantly more decreased in adults than in children(P=0.003).Conclusions:In conclusion,the LV diameter was significantly more increased in children than in adults at 6 months after percutaneous ASD ***,cardiac remodeling after percutaneous ASD closure varies in children and adults.

关键词： Atrial septal defect ventricular remodeling

Analytical evaluation and experimental validation on dynamic rocking behavior for shallow foundation considering structural response

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Earthquake Engineering and Engineering Vibration 2022年第1期21卷 37-51页

作者： kil-wan Ko Jeong-Gon ha Dong-Soo Kim Department of Civil and Environmental Engineering UC BerkeleyCalifornia 94720USA Advanced Structures and Seismic Safety Research Division Daejeon 34057Korea Department of Civil and Environmental Engineering KAISTDaejeon 34141Korea

The challenge in the practical application of rocking foundations is the estimation of its performance,particularly the rotation angle,during a strong *** this study,the dynamic rocking behavior for a shallow foundation considering structural response was evaluated through two analytical approaches:the conventional soil-foundation-structure interaction(SFSI)governing equation of a single-degree-of-freedom(SDOF)structure on a rocking shallow foundation,and the housner rocking model(i.e.,a rocking rigid block on a rigid base).Both approaches were validated with dynamic centrifuge *** test models consisted of a soft soil deposit,a shallow rectangular foundation,and an SDOF structure dominated by a bending behavior.A total of 11 foundation-structure systems and six seismic waves,including recorded earthquake signals and sinusoidal waves,were *** results showed that the conventional SFSI equation well predicted the maximum rotation during strong ***,this method was less accurate regarding the rotational phase information and maximum rotation of the foundation during weak *** the other hand,although the modified housner′s rocking model required five parameters relevant to a soil-foundation-structure system,it overestimated the maximum rotation of the foundation when compared with the results from dynamic centrifuge tests.

关键词： soil-foundation-structure interaction maximum rotation angle rocking foundation housner rocking model dynamic centrifuge test

Endoscopic submucosal dissection for undifferentiated-type early gastric cancer: Do we have enough data to support this?

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world Journal of Gastroenterology 2014年第14期20卷 3938-3949页

作者： Choong Nam Shim Sang kil Lee Department of Internal Medicine Institute of GastroenterologyYonsei University College of Medicine

Although endoscopic submucosal dissection (ESD) is now accepted for treatment of early gastric cancers (EGC) with negligible risk of lymph node (LN) metastasis, ESD for intramucosal undifferentiated type EGC without ulceration and with diameter ≤ 2 cm is regarded as an investigational treatment according to the Japanese gastric cancer treatment guidelines. This consideration was largely based on the analysis of surgically resected EGCs that contained undifferentiated type EGCs; however, results from several institutes showed some discrepancies in sample size and incidence of LN metastasis. Recently, some reports about the safety and efficacy of ESD for undifferentiated type EGC meeting the expanded criteria have been published. Nonetheless, only limited data are available regarding long-term outcomes of ESD for EGC with undifferentiated histology so far. At the same time, endoscopists cannot ignore the patients’ desire to guarantee quality of life after the relatively non-invasive endoscopic treatment when compared to conventional surgery. To satisfy the needs of patients and provide solid evidence to support ESD for undifferentiated EGC, we need more delicate tools to predict undetected LN metastasis and more data that can reveal predictive factors for LN metastasis.

关键词： Early gastric cancer Endoscopic submucosal dissection Undifferentiated histology Indications