Damage diagnostic technique combining machine learning approach with a sensor swarm

A Model-free approach is particularly valuable for Structural Health Monitoring because real structures are often too complex to be modelled accurately, requiring anyhow a large quantity of sensor data to be processed. In this context, this paper presents a machine learning technique that analyses data acquired by swarm of a sensor. The proposed algorithm uses unsupervised learning and is based on the use principal component analysis and symbolic data analysis: PCA extracts features from the acquired data and use them as a template for clustering. The algorithm is tested with numerical experiments. A truss bridge is modelled by a finite element model, and structural response is produced in healthy and several damaged scenarios. The present research shows also the importance of considering a sufficient number of measurements points along the structure, i.e. the swarm of sensors. This technology, which nowadays is easily attainable with the application of optical Fiber Bragg Grating strain sensors. The difficulties related to the early stage damage detection in complex structures can be skipped, especially when ambient, narrow band, moving loads are considered, enhancing the prediction capabilities of the proposed algorithm

Penentuan Jenis Nyamuk Mansoniasebagai Tersangka Vektor Filariasis Brugia Malayi dan Hewan Zoonosis di Kabupaten Muaro Jambi

Filariasis merupakan penyakit yang tidak mudah menular. Filariasis adalah penyakit yang ditularkan oleh nyamuk sebagai vector. Jenis nyamuk yang dapat berperan sebagai vector filariasis dipengaruhi oleh jenis cacing penyebab filaria. Brugia spp. umumnya ditularkan oleh nyamuk Mansonia spp dan Anopheles spp. Vektor dan hewan zoonosis merupakan salah satu factor yang dapat perlu mendapat perhatian dalam pengendalian filariasis. Penelitian terhadap vector dan hewan zoonosis telah dilakukan di Kabupaten Muaro Jambi untuk mengidentifikasi bionomik vektor dan kemungkinan adanya hewan zoonosis yang berperan sebagai penular filariasis. Desain penelitian adalah observasi, yaitu dengan melakukan penangkapan nyamuk dan pemeriksaan darah terhadap kucing. Jumlah kucing yang diperiksa sebanyak 18 ekor. Kucing yang positif microfilaria sebanyak 1 ekor. Jumlah nyamuk Mansonia spp. tertangkap sebanyak 1,167 ekor yang terdiri dari 6 species. Spesies nyamuk tertangkap paling banyak adalah Mansonia uniformis sebanyak 1.010 ekor dengan angka kekerapan 1,0. Berdasarkan hasil tersebut, maka diperlukan peran serta masyarakat untuk mengurangi kepadatan nyamuk dengan membersihkan genangan air dan mencegah gigitan nyamuk. Selain itu diperlukan juga penanganan terhadap hewan yang bertindak sebagai zoonosis dengan memberikan pengobatan terhadap kucing agar tidak menjadi sumber infeksi.Keywords : filariasis, Mansonia, vektor, zoonosis, Muaro Jambi.AbstractFilariasisis noteasily transmitted diseases. Filariasisis transmitted by mosquito vectors. Various types of mosquitoes can act as vectors of filariasis, depending on the type of microfilaria. Brugia spp. are generally transmitted by Mansonia spp and Anopheles spp. Vector and zoonotic animal are the factors that can transmit filariasis and need to have attention for controlling filariasis. Research on vector and zoonotic had been done in Muaro Jambi to determine bionomic vector and the possibility of animals can transmit filariasis. The study design was observational survey, that cought mosquitoes and inspection activities zoonotic. Cats that examined were 18. Cat with positive microfilaria was 1 cat. Number of Mansonia spp. captured was 1,167 which consisted of 6 species consisting of 6 species. Mansonia uniformis was the largest species cought numbering 1.010 with 1.00 frequency rate with 1,010 mosquitoes that frequency rate of 1,00. Based on these results, it is necessery for community participation for mosquito control activities and further investigation to cats and cats carried on a positive treatment.Keywords : filariasis, Mansonia, vectors, zoonotic, Muaro Jambi

Shear and Breathing Modes of Layered Materials.

Layered materials (LMs), such as graphite, hexagonal boron nitride, and transition-metal dichalcogenides, are at the center of an ever-increasing research effort, due to their scientific and technological relevance. Raman and infrared spectroscopies are accurate, non-destructive approaches to determine a wide range of properties, including the number of layers, N, and the strength of the interlayer interactions. We present a general approach to predict the complete spectroscopic fan diagrams, i.e., the relations between frequencies and N for the optically active shear and layer-breathing modes of any multilayer comprising N ≥ 2 identical layers. In order to achieve this, we combine a description of the normal modes in terms of a one-dimensional mechanical model, with symmetry arguments that describe the evolution of the point group as a function of N. Group theory is then used to identify which modes are Raman- and/or infrared-active, and to provide diagrams of the optically active modes for any stack composed of identical layers. We implement the method and algorithms in an open-source tool to assist researchers in the prediction and interpretation of such diagrams. Our work will underpin future efforts on Raman and infrared characterization of known, and yet not investigated, LMs

Damping control of polodes, inertia and natural frequencies: Theory and application to automotive suspensions

This paper shows how tunable dampers can help control the instant centre of rotation of a 2D rigid body and its polode in planar motion, which in turn implies that the inertia tensor can also be controlled. For mechanisms equipped with some elasticity the results show that damping can also control their natural frequencies. The foundation of a general theory to control the polode is presented, exploring the chance of an optimal control formulation of the problem via a variational control principle, approached by the LQR (Linear Quadratic Regulator) method, after a suitable linearization. Application to automotive suspension linkages is presented that demonstrates the control of the instant roll centre and axis and consequently its instant roll vibration frequency to optimize the response, when excited by lateral inertia forces

Sub-seismic scale folding and thrusting within an exposed mass transport deposit : A case study from NW Argentina

This work was carried out with support from CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico) - Brazil, BG - Brazil and the University of Aberdeen. We would like to thank the following geologists for their support, camaraderie and countless hours of fieldwork: Arthur Giovannini, Claus Fallgatter, Victoria Valdez, Qun Liu, Carla Puigdomenech, Guilherme Bozetti and Roberto Noll Filho. We thank Christopher Jackson and an anonymous reviewer, whose constructive comments and criticism helped to improve the manuscript.Peer reviewedPostprin

Development the conceptual design of knowledge based system for integrated maintenance strategy and operation

YesThe importance of maintenance has escalated significantly by the increasing of automation in manufacturing process. This condition switches traditional maintenance perspective of inevitable cost into the business competitive driver. Consequently, maintenance strategy and operation decision needs to be synchronized to business and manufacturing concerns. This paper shows the development of conceptual design of Knowledge Based System for Integrated Maintenance Strategy and Operation (KBIMSO). The framework of KBIMSO is elaborated to show the process of how the KBIMSO works to reach the maintenance decision. By considering the multi-criteria of maintenance decision making, the KB system embedded with GAP and AHP to support integrated maintenance strategy and operation which is novel in this area. The KBIMSO is useful to review the existing maintenance system and give reasonable recommendation of maintenance decisions in respect to business and manufacturing perspective