ID: 58552
Title: Changes in plant defense chemistry (pyrrolizidine alkaloids) revealed through high-resolution spectroscopy
Author: Sabrina Carvalho, Mirka Macel, Martin Schlerf, Fatemeh Eghbali Moghaddam, Patrick P J Mulder, Andrew K Skidmore, Wim H van der Putten
Editor: Derek Lichti
Year: 2013
Publisher: Elsevier, Vol 80, June 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Plant defense chemistry, pyrrolizidine alkaloids, spectroscopy, Senecio erucifolius, Senecio inaequidens, Senecio jacobaea
Abstract: Plant toxic biochemicals play an important role in defense against enemies and often are toxic to humans and livestock. Hyperspectral reflectance is an established method for primary chemical detection and could be further used to determine plant toxicity in the field. In order to make a first step for pyrrolizidine alkaloids detection (toxic defense compound aginst mammals and many insects) we studied how such spectral data can estimate plant defense chemistry under controlled conditions.
In a greenhouse, we grew three related plant species that defend against generlist herbivores through pyrrolizidine alkaloids: Jacobaea vulgaris, Jacobaea erucifolia and Senecio inaequidens, and analyzed the relation between spectral measurements and chemical concentrations using multivariate statistics.
Nutrient addition enhanced tertiary-amine pyrrolizidine alkaloids contents of J. vulgaris and J. erucifolia and decrased N-oxide contents in S. inaequidens and J. vulgaris. Pyrrolizidine alkaloids could be predicted with a moderate accuracy. Pyrrolizidine alkaloid forms tertiary-amines and epoxides were predicted with 63% and 56% of the variation explained, respectively. The most relevant spectral regions selected for prediction were associated with electron transitions and C-H, O-H, and N-H bonds in the 1530 and 2100 nm regions.
Given the relatively low concentration in pyrrolizidine alkaloids concentration (in the order of mg g-1) and resultant predictions, it is promising that pyrrolizidine alkaloids interact with incident light. Further studies should be considered to determine if such a non-destructive method may predict changes in PA concentration in relation to plant natural enemies. Spectroscopy may be used to study plant defenses in intact plant tissues, and may provide managers of toxic plants, food industry and multitrophic -interaction researchers with faster and larger monitoring possibilities.
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58551
Title: Derivation of tree skeletons and error assessment using LiDAR point cloud data of varying quality
Author: M Bremer, M Rutzinger, V Wichmann
Editor: Derek Lichti
Year: 2013
Publisher: Elsevier, Vol 80, June 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Laser scanning, Branch extraction, skeletonization, Eigenvectors, data reduction, object-based point cloud analysis
Abstract: The architecture of trees is of particular interest for 3D model creation in forestry and ecological applications. Terrestrial (TLS) and mobile laser sanning (MLS) systems are used to acquire detailed geometrical data of trees. Since 3D point clouds from laser scanning consist of large data amounts representing uninterpreted topographical information including noise and data gaps, an extraction of salient tree structures is important for further applications. We present a fully automated modular workflow for topological reliable reconstruction of tree architecture. Object-based point cloud processing such as branch extraction is combined with tree skeletonization. Branch extraction is performed using a segmentation procedure followed by segment-based analysis of form indices derived from eigenvector metrics. Extracted branch primitives are simplified and connected to line features during skeletonization. The modular workflow allows comprehensive parameter tests and error assessments that are used for calibration of the module parameters with respect to various characteristics of the input data (eg. noise, scanning resolution, and the number of scan positions). The estimated parameter settings are validated using an exemplary MLS data set. The quality of input point cloud data, strongly influencing the quality of the skeleton results, can be improved by the presented branch extraction procedure. The potential for data improvement increases with increasing point densities. For our object-based appoach, we can show that the presence of erroneous structures and filtering artifacts have the strongest influence onto the quality of the derived skeletons. In constrast to traditional skeletonization approaches, the existence of data gaps has less influence onto the results.
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58550
Title: Shadow detection in very high spatial resolution aerial images: A comparative study
Author: K R M Adeline, M Chen, X Briottet, S K Pang, N Paproditis
Editor: Derek Lichti
Year: 2013
Publisher: Elsevier, Vol 80, June 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Shadow detection, urban areas, high spatial resolution, multispectral and hyperspectral
Abstract: Automatic shadow detection is a very important pre-processing step for many remtoe sensing applications, particularly for images acquired with high spatial resolution. In complex urban enviornments, shadows may occupy a significant portion of the image. Ignoring these regions would lead to errors in various applciations, such as atmospheric correction and classification. To better understand the radiative impact of shadows, a physical study was conducted through the simulation of a synthetic urban canyon scene. Its results helped to explain the most common assumptions made on shadows from a physical point of view in the literature. With this understanding, state-of-the-art methods on shadow detection were surveyed and categorized into six classes: histogram thresholding, invariant color models, object segmentation, geometrical methods, physics-based methods, unsupervised and supervised machine learning methods. Among them, some methods were selected and tested on a large dataset of multispectral and hyperspectral airborne images with high spatial resolution. The dataset chosen contains a large variety of typical occidental urban scenes. The results were compared based on accurate reference shadow masks. In these experiments, histogram thresholding on RGB and NIR channels performed the best with an average accuracy of 92.5%, followed by physics-based methods, such as Richter ' s method with 90.0%. Finally, this paper analyzes and discusses the limits algorithms, concluding with some recommendations for shadow detection.
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58549
Title: Texture augmented detection of macrophyte species using decision trees
Author: Cameron Proctor, Yuhong He, Vincent Robinson
Editor: Derek Lichti
Year: 2013
Publisher: Elsevier, Vol 80, June 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Floating macrophytes, image texture, feature selection, Jefferies-Matusita distance, decision trees
Abstract: Image classification using multispectral sensors has shown good performance in detecting macrophytes at the species level. However, species level classification often does not utilize the texture information provided by high resolution images. This study investigated whether image texture provides useful vector(s) for the discrimination of monospecific stands of three floating macrophyte species in Quickbird imagery of the South Nation River. Semivariograms indicated that window sizes of 5 x 5 and 13 x 13 pixels were the most appropriate spatial scales for calculation of the grey level co-occurrence matrix and subsequent texture attributes from the multispectral and panchromatic bands. Of the 214 investigated vectors (13 Haralick texture attributes * 15 bands +9 spectral bands +10 transformations/indices), feature selection determined which combination of spectral and textural vectors had the greatest class separability based on the Mann-Whitney U-test and Jefferies - Matusita distance. While multispectral red and near infrared (NIR) performed satisfactorily, the addition of panchromatic -dissimilarity slightly improved class separability and the accuracy of a decision tree classifier (Kappa: red/NIR/panchromatic-dissimilarity-93.2% versus red/NIR-90.4%). Class separability improved by incorporating a second texture attribute, but resulted in a decrease in classification accuracy. The results suggest that incorporating image texture may be beneficial for separating stands with high spatial heterogeneity. However, the benefits may be limited and must be weighed against the increased complexity of the classifier.
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58548
Title: On the use of compact polarimetry SAR for ship detection
Author: G E Atteia, Michael J. Collins
Editor: Derek Lichti
Year: 2013
Publisher: Elsevier, Vol 80, June 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Ship detection, polarimetry, compact polarimetry, synthetic aperture radar
Abstract: Quad-pol data are generally acknowledged as providing the highest performance in ship detection applications using SAR data. Yet quad-pol data have half the swath width of single and dual-pol data adn are thus less useful for maritime surveillance, where wide area coverage is crucial. Compact polarimetry (CP)has been proposed as a compromise between swath width and polarization information. The circular-transmit-linear-receive (CTLR) CP data have certain engineering advantages over other CP configurations. CP data may be used to reconstruct a reduced quad-pol covariance matrix (termed pseudo-quad, or PQ, data) and the potential of these data in terrestrial applications has recently been demonstrated. We present some of the first results on the use of CTLR data and reconstructed quad-pol data for ship detection. We use Radarsat-2 fine-quad (FQ) data to examine 76 ships over a range of incidence angles and ship orientations at low to moderate wind speeds. We examined the ship detection performance of full quad-pol and full-PQ data; several dual-pol configurations suggested in the literature, HV and PQ HV and the raw CTLR data. We find that the ship detection performance of the PQ HV data is the strongest of all the detectors we examined, with performance that was comparable to quad-pol data. Other strong performers were HV and CTLR data.
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58547
Title: Flickermeter and its application for lighting apparatus
Author: Pranati Panigrahi, Bibhu Prasad Nanda and Prof Rabinarayana Parida
Editor: Mahadevan Iyer
Year: 2013
Publisher: A Chary Publication, Vol 53, No 6, June 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: Electrical India
Keywords: Flickermeter
Abstract: Flickermeter is a term used for a system that measures the obnoxiousness of flicker caused by voltage fluctuations. The processing performed by a signal chain of this system is very complicated. Thus, it is not easy to obtain the output values only by analytical mean. The short-term flicker severity indicator Pst is the output signal of a so-called flickermeter system that makes it possible to estimate the obnoxiousness of flicker caused by voltage fluctuations. The processing characteristic of the flickermeter is based on a limited set of standard points. In this article, the results of the analysis of a simplified model of this system are presented. The model consists of a set of equations that interpolate and extrapolate the transformation characteristic for modulation with a sinusoidal modulating signal. The proposed deterministic model makes it easier to understand the processing being performed in the examined signal chain.
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58546
Title: An industrial power management system for uninterrupted power supply and no black outs
Author: Arvind Mehta and Amrita Tandon
Editor: Mahadevan Iyer
Year: 2013
Publisher: A Chary Publication, Vol 53, No 6, June 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: Electrical India
Keywords: on-site generation
Abstract: With industrial power users seeking electric power system reliability and energy efficiencies, power generation capabilities are becoming increasingly popular. As the number of onsite generation increases, so does the need arises for more powerful means to monitor and optimize power generation and load management throughout facilities. Power Management and Control System is designed specifically for industrial customers with on-site generation or significant imported power. The system contains automated control functions specifically designed to prevent, detect and mitigate system black-outs. This system enables operators, maintenance and engineering staff to diagnose system events, predicts equipment failures and minimizes unnecessary maintenance.
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58545
Title: Energy management for motors, systems and electrical equipment - A report
Author: Dr L Ashok Kumar
Editor: Mahadevan Iyer
Year: 2013
Publisher: A Chary Publication, Vol 53, No 6, June 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: Electrical India
Keywords: electric energy system, Volatile renewable energy sources, electro-mobility
Abstract: The classical modus operandi of electric energy systems is unidirectional and top-down oriented. A limited number of large power plants feed into the grid and try to keep demand and supply balanced at all times. This balance is a very crucial aspect in operating an electric energy system. Volatile renewable energy sources and electro-mobility are new challenges to this balance and call for sophisticated control methods. Using the load as an additional degree of freedom is not entirely new but affordable global communication infrastructre and embedded systems make it now relatively easy to add a certain portion of "smart" to the loads.
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58544
Title: Why consume our diesel more, in your DG set
Author: Ashok S
Editor: Mahadevan Iyer
Year: 2013
Publisher: A Chary Publication, Vol 53, No 6, June 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: Electrical India
Keywords: Solar Renewable
Abstract: We are used to low cost subsidized Electricity from the national and state grid till now. And today due to power cuts, we are forced to run our DG set to meet our production demands, but at high cost of electricity. Given herein are the finer points of DG operation and maintenance to get the optimum units per liter at sustained DG set efficiency over years. The whole world is thinking to switch over from Diesel and fossil fuel alternatives of power generation to Solar Renewable. Let us take a Small Step today to curb the diesel use in DG sets today and plunge for Giant Leap Tomorrow Early.
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58543
Title: Application of optimal control strategy to automatic generation control of 3-area power systems with EHVAC-HVDC inter-ties
Author: Prof Prabhat Kumar
Editor: Mahadevan Iyer
Year: 2013
Publisher: A Chary Publication, Vol 53, No 6, June 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: Electrical India
Keywords: AGC regulators, hydro-thermal power systems
Abstract: This article applies the modern control theory to design optimal AGC regulators using full state vector feedback for 3-area interconnected hydro-thermal power systems and implemented under considerations in the wake of 1% step load perturbation in thermal/hydro area. For the present study, power system model consists of one area with reheat thermal power plants and two areas with hydro power plants having identical capacity. The system interconnection is considered as EHVAC in parallel with HVDC transmission link. The HVDC link is considered to be operating in constant current control mode. The system responses have been simulated in Mat lab. Responses of deviation in frequencies, deviation in tie line powers (AC as well DC) and integral of area control errors have been plotted for three areas. Thus, on the basis of these responses, the dynamic performance of the system has been studied. Besides this, to study the closed loop system stability, the closed loop system eigen values have been computed.
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58542
Title: Availability based tariff (energy) metering
Author: Dinesh Pawar
Editor: Mahadevan Iyer
Year: 2013
Publisher: A Chary Publication, Vol 53, No 6, June 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: Electrical India
Keywords: Availability Tariff,
Abstract: The term Availability Tariff, particularly in the Indian context, stands for a rational tariff structure for power supply from generating stations, on a contracted basis. The cost of power plants has been divided into fixed and variable costs. The fixed cost elements are interest on loan, return on equity, depreciation, O & M expenses, insurance, taxes and interest on working capital. The variable cost comprises of the fuel cost, i.e., coal & oil in case of thermal plants and nuclear fuel in case of nuclear plants.
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58541
Title: None
Author: None
Editor: Prof Arup Dasgupta
Year: 2013
Publisher: Geospatial Media and Communications Pvt. Ltd, Vol 3, Issue 6, Januaryl 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: Geospatial World
Keywords: None
Abstract: None
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58540
Title: Land administration in Liberia: through war & peace
Author: Nigel Edmead
Editor: Prof Arup Dasgupta
Year: 2013
Publisher: Geospatial Media and Communications Pvt. Ltd, Vol 3, Issue 9, April 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: Geospatial World
Keywords: Liberia,
Abstract: Over 20 years of civil war left Liberia in a disarray, with land rights at the centre of the chaos. Now, technologyis helping to heal the war wounds and resolve the land crisis.
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58539
Title: Clean and high-efficiency coal-fired power generation in the Shenhua group
Author: Chen Yinbiao
Editor: Gu Dazhao
Year: 2013
Publisher: John Wiley & Sons, Inc., Vol 1, Issue 1, 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: Corner Stone - the official journal of the world coal industry
Keywords: None
Abstract: None
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None
ID: 58538
Title: Coal/biomass coprocessing strategy to enable a thriving coal industry in a carbon-constrained world
Author: Robert H Williams
Editor: Gu Dazhao
Year: 2013
Publisher: John Wiley & Sons, Inc., Vol 1, Issue 1, 2013
Source: Centre for Ecological Sciences
Reference: None
Subject: Corner Stone - the official journal of the world coal industry
Keywords: None
Abstract: None
Location: TE12, New Biological Sciences, IISc
Literature cited 1: None
Literature cited 2: None