• The Mathematical Education
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• v.32 no.1
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• pp.75-90
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• 1993

Decision making in uncertain situations that preferences of decision maker is important consists of a series of related decisions. Rule-based expert system can not represent such a complex decision problems. For these decision problems, this paper suggests a new methods IDPI(Influence Diagram-based Probabilistic Inference) which combines model-based knowledge representation and probabilistic inference, and implements a career counsellor for the university students using the combined methods.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.9 no.3
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• pp.185-190
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• 2009

A scheme of expert system based on iterative learning control is proposed. Iterative learning control can obtain control experience from the historical data to build the knowledge base of expert system. Considering some uncertain factors, a flexible measure is adopted in iterative learning control (ILC). Simulation proves the feasibility and effect of the air conditioning control expert system based on flexible iterative learning control (F-ILC). Finally, a feedback compensation unit is incorporated against irregular heavy disturbance.

• Industrial Engineering and Management Systems
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• v.15 no.4
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• pp.354-363
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• 2016

Due to uncertain environment, various parameters such as price, queuing length, warranty, and so on influence on inventory models. In this paper, an inventory-queuing-pricing problem with continuous review inventory control policy and batch arrival queuing approach, is presented. To best of our knowledge, (I) demand function is stochastic and price dependent; (II) due to the uncertainty in real-world situations, a fuzzy programming approach is applied. Therefore, the presented model with goal of maximizing total profit of system analyzes the price and order quantity decision variables. Since the proposed model belongs to NP-hard problems, Pareto-based approaches based on non-dominated ranking and sorting genetic algorithm are proposed and justified to solve the model. Several numerical illustrations are generated to demonstrate the model validity and algorithms performance. The results showed the applicability and robustness of the proposed soft-computing-based approaches to analyze the problem.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2283-2286
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• 2000

Sliding control is a powerful approach to controlling nonlinear and uncertain systems. Conventional sliding mode control suffer' from high control gain and chattering problem. also it needs mathematic! modeling equations for control systems. A Fuzzy controller is endowed with control rules and membership function that are constructed on the knowledge of expert, as like intuition and experience. but It is very difficult to obtain the exact values which are the membership function and consequent parameters. In this paper, without mathematical modeling equations, the plant parameters in sliding mode are estimated by the indirect adaptive fuzzy method. the proposed algorithm could analyze the system's stability and convergence behavior using Lyapunov theory. so sliding modes are reconstructed and decreased tracking error. moreover convergence time took a short. An example of inverted pendulum is given for demonstration of the robustness of proposed methodology.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.5
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• pp.435-439
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• 2009

The peripheral ossifying fibroma(POF) is a relatively common, non-neoplastic gingival growth that is classified as a reactive hyperplastic inflammatory lesion. The clinical appearance of POF is generally a small, well-circumscribed, focal mass with a sessile or pedunculated base. The pathogenesis of this lesion is uncertain. POFs are believed to arise from cells of the periodontal ligament as hyperplastic growth of tissue that is unique to the gingival mucosa. Approximately 60% of POFs occur in the maxilla, and 55%-60% of all cases occur in the incisor-canine area. Most lesions are less than 2 cm in size. To our knowledge, huge POF of approximately 8 cm in size in the lower posterior edentulous ridge has not been previously described in the English literature. We report an unusually huge POF overlying the lower posterior edentulous ridge mucosa, along with long-term follow up result.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.1297-1300
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• 1993

Machine learning in an uncertain or unknown environment is of vital interest to those working with intelligent systems. The ability to garner new information, process it, and increase the understanding/ capability of the machine is crucial to the performance of autonomous systems. The field of artificial intelligence provides two major approaches to the problem of knowledge engineering-expert systems and neural networks. Harnessing the power of these two techniques in a hybrid, cooperating system holds great promise.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.5
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• pp.315-322
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• 2004

A direct adaptive state-feedback controller for highly nonlinear systems is proposed. This paper considers uncertain or ill-defined nonaffine nonlinear systems and employs a static fuzzy logic system (FLS). The employed FLS estimates. and adaptively cancels an unknown plant nonlinearity using its proved universal approximation property. A control law and adaptive laws for unknown fuzzy parameters and bounding constant are established so that the whole closed-loop system is stable in the sense of Lyapunov. The tracking error is guaranteed to be uniformly asymptotically stable rather than uniformly ultimately bounded with the aid of an additional robustifying control term. No a priori knowledge of an upper bound on an lumped uncertainty is required.

• International journal of advanced smart convergence
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• v.8 no.1
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• pp.133-140
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• 2019

In this paper, we present an algorithm for adjusting degree of belief for consistency on the evidence dependency network where various sets of evidence support different sets of hypotheses. It is common for experts to assign higher degree of belief to a hypothesis when there is more evidence over the hypothesis. Human expert without knowledge of uncertainty handling may not be able to cope with how evidence is combined to produce the anticipated belief value. Belief in a hypothesis changes as a series of evidence is known to be true. In non-monotonic reasoning environments, the belief retraction method is needed to clearly deal with uncertain situations. We create evidence dependency network from rules and apply the evidence retraction algorithm to refine belief values on the hypothesis set. We also introduce negative belief values to reflect the reverse effect of evidence combination.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.170-180
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• 2010

With development of the earth's subsurface space, the need for a reliable subsurface spatial model such as a cross-section, boring log is increasing. However, the ground mass was essentially uncertain. To generate model was uncertain because of the shortage of data and the absence of geotechnical interpretation standard(non-statistical uncertainty) as well as field environment variables(statistical uncertainty). Therefore, the current interpretation of the data and the generation of the model were accomplished by a highly trained experts. In this study, a geotechnical ontology model was developed using the current expert experience and knowledge, and the information content was calculated in the ontology hierarchy. After the relative distance between the information contents in the ontology model was combined with the distance between cluster centers, a cluster analysis that considered the geotechnical semantics was performed. In a comparative test of the proposed method, k-means method, and expert's interpretation, the proposed method is most similar to expert's interpretation, and can be 3D-GIS visualization through easily handling massive data. We expect that the proposed method is able to generate the more reasonable subsurface spatial information model without geotechnical experts' help.

• Tuberculosis and Respiratory Diseases
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• v.69 no.4
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• pp.284-287
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• 2010

We report the case of a 68-year-old man with a stromal tumor of uncertain malignant potential (STUMP), which had metastasized to the lung. The patient complained of an enlarged mass in the anterior chest. Chest computed tomography (CT) showed a sternal abscess with multiple nodules in both lungs. A thoracoscopic lung biopsy of the nodules and incision/drainage of the sternal mass were performed simultaneously. CT of the pelvis revealed an enlarged prostate with irregular cystic lesions in the pelvis. Prostate biopsy was done and demonstrated hypercellular stroma with minimal cytological atypia, a distinct pattern of STUMP. The sternal abscess proved to be tuberculosis and the lung lesion was consistent with STUMP, which had spread from the prostate. However, to our knowledge, the tuberculous abscess might not be assoicated with STUMP in the lung. The patient refused surgical prostatectomy and was discharged with anti-tuberculosis medication. On one-year follow up, the patient had no evidence of disease progression.