To effectively diagnose the deterministic faults of a LPRE ground-testing bed, the fault diagnosis method based on PCA and SOM is proposed. The dimension reduction process of PCA not only reduces data size, but also reduces noise influence. It also implements a visualization of fault status identification and fault variable orientation by SOM. Simulation and real fault data results indicate tha...

A 30GHz optically injection-locked self-oscillating optoelectronic mixer (OIL-SOM) is implemented with a high-performance InP/InGaAs heterojunction phototransistor. The sub-harmonic conversion efficiency and phase noise characteristics of OIL-SOM are investigated and used for analyzing OIL-SOM-based 60GHz radio-on-fiber downlink data transmission performance. The OIL-SOM characteristics provide...

In this paper, a new powerful method in artificial neural networks, called modular network SOM (mnSOM) is introduced. mnSOM is a generalization of Self Organizing Maps (SOM) formed by replacing each vector unit of SOM with function module. The modular function could be a multi layer perceptron, a recurrent neural network or even SOM itself. Having this flexibility, mnSOM becomes a new powerful ...

The self-organizing map (SOM) has been widely used as a software tool for visualization of high-dimensional data. Important SOM features include information compression while trying to preserve topological and metric relationship of the primary data items. The assumption of topological preservation in SOMs is not true for many data mappings involving dimension reduction. With the automation of ...

Abstract. Random Forest (RF) is a powerful ensemble method for classification and regression tasks. It consists of decision trees set. Although, a single tree is well interpretable for human, the ensemble of trees is a black-box model. The popular technique to look inside the RF model is to visualize a RF proximity matrix obtained on data samples with Multidimensional Scaling (MDS) method. Here...

Self-organizing maps (SOM) have been successfully applied in many fields of research. In this paper, we demonstrate the use of SOM-based method for the analysis of Expandable PolyStyrene (EPS) batch process. To this end, a data set of EPS-batch process was used for training a SOM. Reference vectors of the SOM were then classified by K-means algorithm into six clusters, which represent product t...

Digitala resurser i undervisningen, flexibelt lärande och lärandesituationen för utländska studenter står i fokus i aprilnumret av Lärande i LTH. I den första artikeln presenterar sig Genombrottets gästprofessor Linda Price, som forskar och undervisar om användning av digitala resurser inom högre utbildning. Linda Price har vid LTH ansvar för kursen ”Supporting Learning through Digital Resource...

Studying the influence of climatic and/or site-specific factors on soil organic matter (SOM) along an elevation gradient is important for understanding the response of SOM to global warming. We evaluated the composition of SOM and structure of humic acids along an altitudinal gradient from 600 to 1400 m in moso bamboo (Phyllostachys edulis) plantations in central Taiwan using NMR spectroscopy a...

Somatostatin (Som), one of the most concentrated neuropeptides in the brain, is highly expressed in the olfactory bulb (OB). However, the temporal profile by which OB somatostatin-expressing (Som+) interneurons are produced and the molecular mechanisms controlling this profile are totally unknown. In the present study, we found that all the Som+ interneurons in the mouse external plexiform laye...