{"title":"Retina encoder tuning and data encryption for learning retina implants","authors":"O. Baruth, R. Eckmiller, D. Neumann","doi":"10.1109/IJCNN.2003.1223872","DOIUrl":"https://doi.org/10.1109/IJCNN.2003.1223872","url":null,"abstract":"A retina encoder (RE) as part of a visual prosthesis (retina implant) for blind subjects with retinal degenerative disorders was implemented by an array of 256 tunable spatio-temporal filters (ST) to map visual patterns P1 onto encoded output patterns as functional approximation of retina information processing. These RE-output signals were fed into a visual system module (VM) to simulate the mapping (by the central visual system) of the retinal output onto visual percepts P2, which were visualized on a monitor. Alternative tuning strategies for roaming within the large spatio-temporal state space of RE were developed and tested. Initially, VM as neural network was trained to generate a P2 very similar to a selected set of P1s by feeding the corresponding RE-outputs into VM. RE tuning was tested by presenting a given small set of P1s to the serial coupling of RE and VM and by monitoring a modified Hamming distance between P2 and P1, while the ST-parameters were tuned. Human volunteers with normal vision were asked to approximate P2 to P1 directly, with random search, or by means of a dialog-based tuning with an evolutionary algorithm (EA). Typically, dialog-based EA tuning reached the optimal similarity between P2 and P1 (limited by the quality of VM) within less than 200 iterations. In contrast, manual tuning required considerably more iteration steps and converged to a smaller similarity between P2 and P1. Structure and function of our tunable RE offer not only an optimization of visual perception, but may also be important to serve as technical encryption unit (EU) in connection with the human central visual system as biological decryption unit (DU); an important feature to meet the authentication requirements of active medical devices.","PeriodicalId":310128,"journal":{"name":"Proceedings of the International Joint Conference on Neural Networks, 2003.","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126814938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Genetic learning of functional link networks","authors":"C. Bhumireddy, C. Chen","doi":"10.1109/IJCNN.2003.1223385","DOIUrl":"https://doi.org/10.1109/IJCNN.2003.1223385","url":null,"abstract":"A genetic learning algorithm is proposed for supervised learning of Guassian-type of functional link networks (FLN), where Gaussian functions are used in the functional nodes. The parameters to be adjusted using genetic approach are weights between input layer and functional nodes, and parameters, i.e., center and width, of Gaussian functions (radial basis functions) in the functional nodes. Genetic coding is used for combining evolution of weights and Gaussian parameters in a single chromosome. Singular value decomposition (SVD) is used for computing the weights in the output layer. The proposed approach is efficient in terms of computational efficiency and time complexity as demonstrated with several benchmark datasets. The simulations indicate that proposed approach yields consistent results and near optimal solution, which is superior to previous approaches.","PeriodicalId":310128,"journal":{"name":"Proceedings of the International Joint Conference on Neural Networks, 2003.","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123914682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Two-cell cellular neural networks: generation of new hyperchaotic multiscroll attractors","authors":"D. Cafagna, G. Grassi","doi":"10.1109/IJCNN.2003.1223814","DOIUrl":"https://doi.org/10.1109/IJCNN.2003.1223814","url":null,"abstract":"In this paper the attention is focused on the complex dynamic phenomena generated by cellular neural networks (CNNs). By taking as basic cell Chua's circuit with sine-type nonlinearity, it is shown that a simple two-cell CNN is able to generate hyperchaotic behaviors. In particular, the paper shows that new multiscroll attractors can be obtained by modifying circuit parameters related to the cell nonlinearities. Finally, different examples are reported to illustrate the effectiveness and robustness of the proposed approach.","PeriodicalId":310128,"journal":{"name":"Proceedings of the International Joint Conference on Neural Networks, 2003.","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123969034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Robust recognition based on adaptive combination of weak classifiers","authors":"Guoping Wang, M. Pavel, Xubo B. Song","doi":"10.1109/IJCNN.2003.1223765","DOIUrl":"https://doi.org/10.1109/IJCNN.2003.1223765","url":null,"abstract":"We describe a novel adaptive method that achieves robustness in pattern classification by combining a large number of weak classifiers. The individual classifiers are trained on subsets of features of the training samples and the output classification is obtained by a weighted sum of the individual weak classifiers. When the classifier is applied to the test set, the combination weights are adaptively adjusted in accordance with the agreement among the individual classifiers. We evaluated the performances of several different combination methods using simulated data and the results proved to be robust.","PeriodicalId":310128,"journal":{"name":"Proceedings of the International Joint Conference on Neural Networks, 2003.","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114213197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Processing of analogy in the thalamocortical circuit","authors":"Y. Choe","doi":"10.1109/IJCNN.2003.1223916","DOIUrl":"https://doi.org/10.1109/IJCNN.2003.1223916","url":null,"abstract":"The corticothalamic feedback and the thalamic reticular nucleus have gained much attention lately because of their integrative and modulatory functions. A previous study by the author suggested that this circuitry could process analogies (i.e., the analogy hypothesis). In this paper, the proposed model was implemented as a network of leaky integrate-and-fire neurons to test the analogy hypothesis. The previous proposal required specific delay and temporal dynamics, and the implemented network tuned accordingly functioned as predicted. Furthermore, these specific conditions turn out to be consistent with experimental data, suggesting that a further investigation of the thalamocortical circuit within the analogical framework may be worthwhile.","PeriodicalId":310128,"journal":{"name":"Proceedings of the International Joint Conference on Neural Networks, 2003.","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116213695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Martín-Clemente, S. Hornillo-Mellado, J. I. Acha, F. R. Ruiz, C. Puntonet
{"title":"Neural net with two hidden layers for non-linear blind source separation","authors":"R. Martín-Clemente, S. Hornillo-Mellado, J. I. Acha, F. R. Ruiz, C. Puntonet","doi":"10.1109/IJCNN.2003.1223461","DOIUrl":"https://doi.org/10.1109/IJCNN.2003.1223461","url":null,"abstract":"In this paper, we present an algorithm that minimizes the mutual information between the outputs of a multilayer perceptron (MLP). The neural network is then used as separating system in the nonlinear blind source separation problem. It has been reported that MLPs with one hidden layer are sufficient to achieve desirable performance. However, in some cases, we may prefer approximating nonlinear mappings by using networks with several hidden layers. For the sake of simplicity, the present paper is focused on MLPs with two hidden layers. The performance is illustrated by some experiments.","PeriodicalId":310128,"journal":{"name":"Proceedings of the International Joint Conference on Neural Networks, 2003.","volume":"276 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116215865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Feature selection assessment and comparison using two saliency measures in an Elman recurrent neural network","authors":"T. I. Laine, K. Bauer","doi":"10.1109/IJCNN.2003.1224016","DOIUrl":"https://doi.org/10.1109/IJCNN.2003.1224016","url":null,"abstract":"This paper provides a summary of a feasibility study conducted to assess and compare a weight based and a network output sensitivity based saliency measure for use with an Elman recurrent neural network (RNN). An experiment was designed to assign temporal data with significant noise, autocorrelation and crosscorrelation into one of two classes. To improve classification accuracy, feature saliency screening was performed to select a subset of the eight candidate input features using a weight based signal-to-noise ratio and an output sensitivity based measure. With consistent selection and ranking of features observed between the two saliency measures, both indicated a parsimonious subset of three of the original eight input features should be retained. Using CPU time as a surrogate measure of operations required, the computational efficiency was also found equivalent, with an observed difference of less than 2.5% between methods. Numerical results show a parsimonious subset of features improved generalization by significantly reducing the classification accuracy variance for multiple data sets and trained RNNs across time periods. An increase in classification accuracy for the last time period was even obtained for an independent validation set using the reduced feature set.","PeriodicalId":310128,"journal":{"name":"Proceedings of the International Joint Conference on Neural Networks, 2003.","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116342863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The role of temporal coding in the processing of relational information in the mind-brain","authors":"L. Shastri","doi":"10.1109/IJCNN.2003.1223897","DOIUrl":"https://doi.org/10.1109/IJCNN.2003.1223897","url":null,"abstract":"All facets of high-level cognition, including perception, language, memory, and action, involve relational information (e.g., What is where? and Who did what to whom?). In order to process relational information, the brain must be capable of supporting a dynamic, activation-based expression of such information as well as a persistent, structure-based encoding of such information. An important challenge for computational neuroscience is to model the brain's remarkable ability to express and seamlessly integrate both transient and persistent forms of relational information. A brief review of work done by the author and his collaborators on computational models that attempt to address this challenge using temporal synchrony, network structure, and synaptic plasticity is presented.","PeriodicalId":310128,"journal":{"name":"Proceedings of the International Joint Conference on Neural Networks, 2003.","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124124426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Feature guided visual attention with topographic array processing and neural network-based classification","authors":"G. Tímár, D. Bálya, I. Szatmári, C. Rekeczky","doi":"10.1109/IJCNN.2003.1223918","DOIUrl":"https://doi.org/10.1109/IJCNN.2003.1223918","url":null,"abstract":"Biological systems are constantly engulfed in sensory input that must be processed. Attention has evolved to cut down on the magnitude of the input and enable the agent to analyze the most important parts of the information. This is especially true for the visual system where the appropriate field of view and scale must be determined. Our system receives a video flow with considerably higher resolution than the resolution of the cellular neural net based visual microprocessor that computes the topographic features of the input. This process requires a dynamic positioning of the processing window in the video flow. We have developed a fast attention and selection algorithm that allows the system to choose the field of view and scale (zoom) level for the next frame based on the features computed from the current frame and the output of the ART or NNC-based classifiers. The algorithmic framework and hardware architecture of the system are presented along with experimental chip results for several video flows recorded in flying vehicles.","PeriodicalId":310128,"journal":{"name":"Proceedings of the International Joint Conference on Neural Networks, 2003.","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126449758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Incremental learning in dynamic environments using neural network with long-term memory","authors":"K. Tsumori, S. Ozawa","doi":"10.1109/IJCNN.2003.1223973","DOIUrl":"https://doi.org/10.1109/IJCNN.2003.1223973","url":null,"abstract":"When the environment is dynamically changed for agents, knowledge acquired from an environment might be useless in the future environments. Therefore, agents should not only acquire new knowledge but also modify or delete old knowledge. However, these modification and deletion are not always efficient in learning. Because the knowledge once acquired in the past can be useful again in the future when the same environment reappears. To learn efficiently in this situation, agents should have memory to store old knowledge. In this paper, we propose an agent architecture that consists of four modules: resource allocating network (PAN), long-term memory (LTM), association buffer (A-Buffer), and environmental change detector (ECD). In LTM, not only acquired knowledge but also the information about which knowledge was produced in the same environment is stored. This information is utilized for recalling the knowledge acquired in the past when the same environment reappears. To evaluate the adaptability in a class of dynamic environments, we apply this model to a simple problem that some target functions to be approximated are changed in turn. As a result, we verify the following adaptability of RAN-ALTM: (1) incremental learning can be stably carried out, (2) environmental changes are correctly detected, (3) fast adaptation is realized by training some of the accumulated knowledge when the past environments reappear.","PeriodicalId":310128,"journal":{"name":"Proceedings of the International Joint Conference on Neural Networks, 2003.","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126019714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}