bluuebunny/crossref_metadata_2025 huggingface dataset:
Aerosol hygroscopicity and CCN activity obtained from a combination analysis based on size-resolved CCN and aerosol chemical composition observations during the AC3Exp13 campaign
Authors: Zhang F. , Li Z. , Li R. J. , Sun L. , Zhao C. , Wang P. C. , Sun Y. L. , Li Y. N. , Liu X. G. , Li J. X. , Li P. R. , Ren G. , Fan T. Y.
Published: June 2014

Abstract. Aerosol hygroscopicity and cloud condensation nuclei (CCN) activity under clean conditions and polluted events are investigated based on size-resolved CCN and aerosol chemical composition observations during the Aerosol-CCN-Cloud Closure Experiment (AC3Exp) campaign conducted at Xianghe, China in summer 2013. About 14–22% of aerosol particles during the campaign are of externally mixed CCN-inactive particles that cannot serve as CCN under atmospheric typical supersaturation (SS) of ∼0.4%. A high sensitivity of Maximum activation fractions (MAF) to SS under polluted conditions has been observed. The pollutants can cause a maximum MAF decrease of 25–30% (at SS = 0.08%). Hygroscopicity parameter kappa (κ) are about 16–35% lower under polluted conditions than under clean conditions for particles in accumulation size range (80–180 nm); however, for particles in nucleation or Aitken size range (30–60 nm), κ is slightly higher under polluted conditions. A non-parallel observation (NPO) CCN closure study shows low correlation coefficient between estimated and observed CCN number concentrations (NCCN). About 30–40% uncertainties in NCCN prediction are associated with the changes of particle composition. A case study shows that CCN activation ratio (AR) increased with the increase of condensation nuclei (CN) number concentrations (NCN) in relatively clean days. In the case, AR exhibited good correlation with κchem, which is calculated from chemical volume fractions, due to particles mainly composed of soluble inorganics. On the contrary, AR declined with increase of NCN during polluted events when particles composed mostly of organics. Meanwhile, AR is closely related to f44, which is the fraction of total organic mass signal at m/z 44 and closely associated with particle organic oxidation level. Our study highlights the importance of aerosols chemical composition on determining the activation properties of aerosol particles, underlining the importance of long-term observation of CCN under different atmospheric environments, especially those with heavy pollution and high CN number concentrations.
Atmospheric aerosol characterization with a ground-based SPEX spectropolarimetric instrument
Authors: van Harten G. , de Boer J. , Rietjens J. H. H. , Di Noia A. , Snik F. , Volten H. , Smit J. M. , Hasekamp O. P. , Henzing J. S. , Keller C. U.
Published: June 2014

Abstract. Characterization of atmospheric aerosols is important for understanding their impact on health and climate. A wealth of aerosol parameters can be retrieved from multi-angle, multi-wavelength radiance and polarization measurements of the clear sky. We developed a ground-based SPEX instrument (groundSPEX) for accurate spectropolarimetry, based on the passive, robust, athermal and snapshot spectral polarization modulation technique, and hence ideal for field deployment. It samples the scattering phase function in the principal plane in an automated fashion, using a motorized pan/tilt unit and automatic exposure time detection. Extensive radiometric and polarimetric calibrations were performed, yielding values for both random noise and systematic uncertainties. The absolute polarimetric accuracy at low degrees of polarization is established to be ~ 5 × 10−3. About 70 measurement sequences have been performed throughout four clear-sky days at Cabauw, the Netherlands. Several aerosol parameters were retrieved: aerosol optical thickness, effective radius, and complex refractive index for fine and coarse mode. The results are in good agreement with the co-located AERONET products, with a correlation coefficient of ρ = 0.932 for the total aerosol optical thickness at 550 nm.
The Habitable Zone of Inhabited Planets
Authors: Zuluaga J. I. , Salazar J. F. , Cuartas-Restrepo P. , Poveda G.
Published: June 2014

Abstract. In this paper we discuss and illustrate the hypothesis that life substantially alters the state of a planetary environment and therefore, modifies the limits of the HZ as estimated for an uninhabited planet. This hypothesis lead to the introduction of the Habitable Zone for Inhabited Planets (hereafter InHZ), defined here as the region where the complex interaction between life and its abiotic environment is able to produce plausible equilibrium states with the necessary physical conditions for the existence and persistence of life itself. We support our hypothesis of an InHZ with three theoretical arguments, multiple evidences coming from observations of the Earth system, several conceptual experiments and illustrative numerical simulations. Conceptually the diference between the InHZ and the Abiotic HZ (AHZ) depends on unique and robust properties of life as an emergent physical phenomenon and not necesarily on the particular life forms bearing in the planet. Our aim here is to provide conceptual basis for the development of InHZ models incorporating consistently life-environment interactions. Although previous authors have explored the effects of life on habitability there is a gap in research developing the reasons why life should be systematically included at determining the HZ limits. We do not provide here definitive limits to the InHZ but we show through simple numerical models (as a parable of an inhabited planet) how the limits of the AHZ could be modified by including plausible interactions between biota and its environment. These examples aim also at posing the question that if limits of the HZ could be modified by the presence of life in those simple dynamical systems how will those limits change if life is included in established models of the AHZ.
Interactive coupling of regional atmosphere with biosphere in the new generation regional climate system model REMO-iMOVE
Authors: Wilhelm C. , Rechid D. , Jacob D.
Published: June 2014

Abstract. The main objective of this study is the coupling of the regional climate model REMO with a new land surface scheme including dynamic vegetation phenology, and the evaluation of the new model version called REMO with interactive MOsaic-based VEgetation: REMO-iMOVE. First, we focus on the documentation of the technical aspects of the new model constituents and the coupling mechanism. The representation of vegetation in iMOVE is based on plant functional types (PFTs). Their geographical distribution is prescribed to the model which can be derived from different land surface data sets. Here, the PFT distribution is derived from the GLOBCOVER 2000 data set which is available on 1 km × 1 km horizontal resolution. Plant physiological processes like photosynthesis, respiration and transpiration are incorporated into the model. The vegetation modules are fully coupled to atmosphere and soil. In this way, plant physiological activity is directly driven by atmospheric and soil conditions at the model time step (two minutes to some seconds). In turn, the vegetation processes and properties influence the exchange of substances, energy and momentum between land and atmosphere. With the new coupled regional model system, dynamic feedbacks between vegetation, soil and atmosphere are represented at regional to local scale. In the evaluation part, we compare simulation results of REMO-iMOVE and of the reference version REMO2009 to multiple observation data sets of temperature, precipitation, latent heat flux, leaf area index and net primary production, in order to investigate the sensitivity of the regional model to the new land surface scheme and to evaluate the performance of both model versions. Simulations for the regional model domain Europe on a horizontal resolution of 0.44° had been carried out for the time period 1995–2005, forced with ECMWF ERA-Interim reanalyses data as lateral boundary conditions. REMO-iMOVE is able to simulate the European climate with the same quality as the parent model REMO2009. Differences in near-surface climate parameters can be restricted to some regions and are mainly related to the new representation of vegetation phenology. The seasonal and interannual variations in growth and senescence of vegetation are captured by the model. The net primary productivity lies in the range of observed values for most European regions. This study reveals the need for implementing vertical soil water dynamics in order to differentiate the access of plants to water due to different rooting depths. This gets especially important if the model will be used in dynamic vegetation studies.
Discovering hidden architectures of ancient time: 3d data survey to reveal the myth of mithra in Santa Maria Capua Vetere
Authors: Campi M. , Catuogno R. , di Luggo A. , Iovane D. , Palomba D.
Published: June 2014

Abstract. The research illustrated in this paper is part of a wider testing ground, aimed at identifying and developing processes of le arning and development taking place in archaeological contexts. These sites are investigated through the use of advanced technology, based on integrated methods of survey of new generation. The aim is to identify alternative languages of representation, able to read and to represent effectively the analyzed object and to propose alternative enjoyment systems. The case study is the Mithraeum in Santa Maria Capua Vetere, for which were carried out surveys with non-contact techniques, based on the use of instrumentations, for the acquisition of colorimetric and metric informations, that exploit a non-invasive approach. Data coming from laser scanner's sensors, combined with GPS receivers, are processed to define a three-dimensional centimetric space, in a single reference system of individual scans. Purpose of this research is to identify representation techniques able to communicate the sense of the multiple interrelations and of interferences among parties, providing the subsequent insertion of data into a wider project of cataloging, fruition and valuation of cultural heritage. The chance to diffuse Digital surveys is now a possible and implementable reality. The purpose is to spread awareness of World Heritage, in a participatory manner and based on the spiri t of knowledge, conveying all the strength of cultural content that heritage has.
Methods and tools to enjoy and to study inaccessible Heritage
Authors: Capone M. , Campi M.
Published: June 2014

Abstract. Our research on a multi-purpose survey of cultural Heritage located in UNESCO Historical Centre of Naples has the following goals: to test some innovative strategies to improve public enjoyment for inaccessible sites; to explore the use of some interactive systems to study heritage in remote; to explore how to access the information system through AR applications. In this paper we are going to focus on comparison between interactive system to access 3D data and photogrammetric processing of panoramic images. We investigated on: a. the use of 360° panorama for 3D restitutions; b. the use of 360° panorama as an interface to 3D data to extract real 3D coordinates and accurately measure distances; c. the use of 3D PDF to access a 3D database.
Impact Assessment of the Renewable Energies in the Cultural Heritage: the Case of the Way of St. James in Spain
Authors: Chias P. , Abad T.
Published: June 2014

Abstract. Medieval town centres and landscapes along the Way of St. James are being affected by renewable energy sources at the architectural, urban and territorial scales. The impact is not only visual, but thermal, accoustic and electromagnetic. Visual impact of solar photovoltaic power plants – which are placed over traditional crops close to the urban borders –, and also wind farms located at the hilltops, are sometimes remarkable. Solar photovoltaic modules are integrated into ancient roofs, and small scale wind turbines are taking up the ancient urban spaces. Among other effects on animal life and vegetation, the rise in temperature, radioelectric interferences, as well as changes in the traditional land uses are noticeable, and a deep analysis is needed. Our main target is to define an integrated methodology which considers all these effects. As a part of our project premises, we work with Open Source programs. We obtained a digital terrain model – 25 m spatial resolution –, and from Corine Land Cover images we got different raster files according to our research targets. Databases where implemented from both remote sensing and measures obtained directly in the field work. We applied GIS based multicriteria decision analysis and weighted linear combination, and then we adapted GRASS tools for a better usability. Our case studies are particularly interesting due to their situation along the Spanish Way of St. James, which is an itinerary named one of UNESCO's World Heritage Sites.
Surveying and mapping a cave using 3d laser scanner: the open challenge with free and open source software
Authors: Cosso T. , Ferrando I. , Orlando A.
Published: June 2014

Abstract. The present work is part of a series of activities involving different skills, in order to explore and document in detail one of the most visited caves in Liguria Region. In this context, in addition to speleologists, geologists, videographers, the geomatic expertise has also been involved to carry out a laser scanner survey, in order to produce a three-dimensional model of the two more easily accessible rooms of the cave. The survey was carried out using Z+F IMAGER® 5010 instrument and the post processing operations related to registration of point clouds have been made with Z+F LaserControl®. Subsequently, two different free and open source software were used: MeshLab, to merge the point clouds and to obtain the final mesh, and CloudCompare, to make filtering on the previous results and to extract sections.
Deformation monitoring with off-the-shelf digital cameras for civil engineering fatigue testing
Authors: Detchev I. , Habib A. , He F. , El-Badry M.
Published: June 2014

Abstract. Deformation monitoring of civil infrastructure systems is important in terms of both their safety and serviceability. The former refers to estimating the maximum loading capacity during the design stages of a building project, and the latter means performing regularly scheduled maintenance of an already existing structure. Traditionally, large structures have been monitored using surveying techniques, while fine-scale monitoring of structural components such as beams and trusses has been done with strain gauge instrumentation. In the past decade, digital photogrammetric systems coupled with image processing techniques have also been used for deformation monitoring. The major advantage of this remote sensing method for performing deformation monitoring is that there is no need to access the object of interest while testing is in progress. The paper is a result of an experiment where concrete beams with polymer support sheets are subjected to dynamic loading conditions by a hydraulic actuator in a structures laboratory. This type of loading is also known as fatigue testing, and is used to simulate the typical use of concrete beams over a long period of time. From a photogrammetric point of view, the challenge for this type of experiment is to avoid motion artifacts by maximizing the sensor frame rate, and at the same time to have a good enough image quality in order to achieve satisfactory reconstruction precision. This research effort will investigate the optimal camera settings (e.g., aperture, shutter speed, sensor sensitivity, and file size resolution) in order to have a balance between high sensor frame rate and good image quality. The results will be first evaluated in terms of their repeatability, and then also in terms of their accuracy. The accuracy of the results will be checked against another set of results coming from high quality laser transducers.
Potentials of small, lightweight and low cost Multi-Echo Laser Scanners for detecting Grape Berries
Authors: Djuricic A. , Weinmann M. , Jutzi B.
Published: June 2014

Abstract. Mobile sensor devices offer great opportunities for automatic scene analysis and object recognition. Nowadays a new generation of ranging devices is available, like laser scanners which are small and light weighted. Concerning these improvements specific applications can be tackled. In this contribution we focus on vineyard monitoring for detecting and counting grape berries with a small, lightweight and low cost multi-echo laser scanner. Therefore a Hokuyo UTM-30LX-EW laser range finder is utilized for capturing the data in close range up to 1m. In order to process the data the following methodology is proposed: after smoothing and morphological techniques are applied on the laserscanning intensity and range images the number of visible grape berries is determined from the resulting segments. The approach performs with a detection accuracy of above 84%. The results reveal the high potential of such close range ranging devices for locating and counting grape berries. Thus, the methodology provides practical support for viticulture applications.
A Fast, Accurate and Easy to Implement Method for Pose Recognition of an Intramedullary Nail using a Tracked C-arm
Authors: Esfandiari H. , Amiri S. , Lichti D.D. , Anglin C.
Published: June 2014

Abstract. A C-arm is a mobile X-ray device that is frequently used during orthopaedic surgeries. It consists of a semi-circular, arc-shaped arm that holds an X-ray transmitter at one end and an X-ray detector at the other. Intramedullary nail (IM nail) fixation is a popular orthopaedic surgery in which a metallic rod is placed into the patient's fractured bone (femur or tibia) and fixed using metal screws. The main challenge of IM-nail fixation surgery is to achieve the X-ray shot in which the distal holes of the IM nail appear as circles (desired view) so that the surgeon can easily insert the screws. Although C-arm X-ray devices are routinely used in IM-nail fixation surgeries, the surgeons or radiation technologists (rad-techs) usually use it in a trial-and-error manner. This method raises both radiation exposure and surgery time. In this study, we have designed and developed an IM-nail distal locking navigation technique that leads to more accurate and faster screw placement with a lower radiation dose and a minimum number of added steps to the operation to make it more accepted within the orthopaedic community. The specific purpose of this study was to develop and validate an automated technique for identifying the current pose of the IM nail relative to the C-arm. An accuracy assessment was performed to test the reliability of the navigation results. Translational accuracy was demonstrated to be better than 1 mm, roll and pitch rotations better than 2° and yaw rotational accuracy better than 2–5° depending on the separate angle. Computation time was less than 3.5 seconds.
A New Approach for Documentation, Conservation and Preservation of the Monolithic Statues in San Agustín as Pilot for Outdoor Cultural Heritage Documentation in Colombia
Authors: Estela A. , Hamacher J.
Published: June 2014

Abstract. The "Instituto Colombiano de Antropología e Historia" (ICANH) started a new conservation project for the "San Agustín Archaeological Park" (Huila, Colombia) in 2013. The objectives of this project are the documentation, conservation, and preservation of the numerous monolithic statues mainly by integrating the use of new technologies (3D models). A first phase of the project has been completed, resulting in three-dimensional models of 66 of the monolithic sculptures in San Agustín. The methodology developed in this first phase will show the way for other heritage sites in Colombia and for subsequent phases applied to the archaeological park. The 3D data has been obtained using two types of data acquisition technology: the Mantis Vision F5 using infrared structured-light (SL) and a laser scanner based on the phase shift (PS) technology, the Z+F Imager 5010. The results show that future phases need improvement in data acquisition. Mainly the data obtained with the hand held scanner shows many lacunae. This article presents the observations during data processing on the basis of one sculpture, "Escultura 23". In conclusion, this first phase showed where to improve for the succeeding ones, for instance the detail of the meshes need to be increased if the models are to be used for detailed conservation and preservation purposes.
Development of a self-localization method using sensors on mobile devices
Authors: Fuse T. , Matsumoto K.
Published: June 2014

Abstract. Recently, development of high performance CPU, cameras and other sensors on mobile devises have been used for wide variety of applications. Most of the applications require self-localization of the mobile device. Since the self-localization is based on GPS, gyro sensor, acceleration meter and magnetic field sensor (called as POS) of low accuracy, the applications are limited. On the other hand, self-localization method using images have been developed, and the accuracy of the method is increasing. This paper develops the self-localization method using sensors, such as POS and cameras, on mobile devices simultaneously. The proposed method mainly consists of two parts: one is the accuracy improvement of POS data in itself by POS sensor fusion based on filtering theory, and another is development of self-localization method by integrating POS and camera. The proposed method combines all POS data by using Kalman filter in order to improve the accuracy of exterior orientation factors. The exterior orientation factors based on POS sensor fusion are used as initial value of ones in image-based self-localization method. The image-based selflocalization method consists of feature points extraction/tracking, coordinates estimation of the feature points, and orientation factors updates of the mobile device. The proposed method is applied to POS data and images taken in urban area. Through experiments with real data, the accuracy improvement by POS sensor fusion is confirmed. The proposed self-localization method with POS and camera make the accuracy more sophisticated by comparing with only POS sensor fusion.
Face Pose Recognition Based on Monocular Digital Imagery and Stereo-Based Estimation of its Precision
Authors: Gorbatsevich V. , Vizilter Yu. , Knyaz V. , Zheltov S.
Published: June 2014

Abstract. A technique for automated face detection and its pose estimation using single image is developed. The algorithm includes: face detection, facial features localization, face/background segmentation, face pose estimation, image transformation to frontal view. Automatic face/background segmentation is performed by original graph-cut technique based on detected feature points. The precision of face orientation estimation based on monocular digital imagery is addressed. The approach for precision estimation is developed based on comparison of synthesized facial 2D images and scanned face 3D model. The software for modelling and measurement is developed. The special system for non-contact measurements is created. Required set of 3D real face models and colour facial textures is obtained using this system. The precision estimation results demonstrate the precision of face pose estimation enough for further successful face recognition.
New knowledge in determining the astronomical orientation of Incas object in Ollantaytambo, Peru
Authors: Hanzalová K. , Klokočník J. , Kostelecký J.
Published: June 2014

Abstract. This paper deals about astronomical orientation of Incas objects in Ollantaytambo, which is located about 35 km southeast from Machu Picchu, about 40 km northwest from Cusco, and lies in the Urubamba valley. Everybody writing about Ollantaytambo, shoud read Protzen (1993). He devoted his monograph to description and interpretation of that locality. Book of Salazar and Salazar (2005) deals, among others, with the orientation of objects in Ollantaytambo with respect to the cardinal direction. Zawaski and Malville (2007) documented astronomical context of major monuments of nine sites in Peru, including Ollantaytambo. We tested astronomical orientation in these places and confirm or disprove hypothesis about purpose of Incas objects. For assessment orientation of objects we used our measurements and also satellite images on Google Earth and digital elevation model from ASTER. The satellite images used to approximate estimation of astronomical orientation. The digital elevation model is useful in the mountains, where we need the really horizon for a calculation of sunset and sunrise on specific days (solstices), which were for Incas people very important. By Incas is very famous that they worshiped the Sun. According to him they determined when to plant and when to harvest the crop. In this paper we focused on Temple of the Sun, also known the Wall of six monoliths. We tested which astronomical phenomenon is connected with this Temple. First, we tested winter solstice sunrise and the rides of the Pleiades for the epochs 2000, 1500 and 1000 A.D. According with our results the Temple isn't connected neither with winter solstice sunrise nor with the Pleiades. Then we tested also winter solstice sunset. We tried to use the line from an observation point near ruins of the Temple of Sun, to west-north, in direction to sunset. The astronomical azimuth from this point was about 5° less then we need. From this results we found, that is possible to find another observation point. By Salazar and Salazar (2005) we found observation point at the corner (east rectangle) of the pyramid by Pacaritanpu, down by the riverside. There is a line connecting the east rectangular "platform" at the river, going along the Inca road up to vicinity of the Temple of the Sun and then in the direction to the Inca face. Using a digital elevation model we found the astronomical azimuth, which is needed for confirm astronomical orientation of the Temple. So, finally we are able to demonstrate a possibility of the solar-solstice orientation in Ollantaytambo.
A contest of sensors in close range 3D imaging: performance evaluation with a new metric test object
Authors: Hess M. , Robson S. , Hosseininaveh Ahmadabadian A.
Published: June 2014

Abstract. An independent means of 3D image quality assessment is introduced, addressing non-professional users of sensors and freeware, which is largely characterized as closed-sourced and by the absence of quality metrics for processing steps, such as alignment. A performance evaluation of commercially available, state-of-the-art close range 3D imaging technologies is demonstrated with the help of a newly developed Portable Metric Test Artefact. The use of this test object provides quality control by a quantitative assessment of 3D imaging sensors. It will enable users to give precise specifications which spatial resolution and geometry recording they expect as outcome from their 3D digitizing process. This will lead to the creation of high-quality 3D digital surrogates and 3D digital assets. The paper is presented in the form of a competition of teams, and a possible winner will emerge.
Smartphones Based Mobile Mapping Systems
Authors: Al-Hamad A. , El-Sheimy N.
Published: June 2014

Abstract. The past 20 years have witnessed an explosive growth in the demand for geo-spatial data. This demand has numerous sources and takes many forms; however, the net effect is an ever-increasing thirst for data that is more accurate, has higher density, is produced more rapidly, and is acquired less expensively. For mapping and Geographic Information Systems (GIS) projects, this has been achieved through the major development of Mobile Mapping Systems (MMS). MMS integrate various navigation and remote sensing technologies which allow mapping from moving platforms (e.g. cars, airplanes, boats, etc.) to obtain the 3D coordinates of the points of interest. Such systems obtain accuracies that are suitable for all but the most demanding mapping and engineering applications. However, this accuracy doesn't come cheaply. As a consequence of the platform and navigation and mapping technologies used, even an "inexpensive" system costs well over 200 000 USD. Today's mobile phones are getting ever more sophisticated. Phone makers are determined to reduce the gap between computers and mobile phones. Smartphones, in addition to becoming status symbols, are increasingly being equipped with extended Global Positioning System (GPS) capabilities, Micro Electro Mechanical System (MEMS) inertial sensors, extremely powerful computing power and very high resolution cameras. Using all of these components, smartphones have the potential to replace the traditional land MMS and portable GPS/GIS equipment. This paper introduces an innovative application of smartphones as a very low cost portable MMS for mapping and GIS applications.
Congruence analysis of point clouds from unstable stereo image sequences
Authors: Jepping C. , Bethmann F. , Luhmann T.
Published: June 2014

Abstract. This paper deals with the correction of exterior orientation parameters of stereo image sequences over deformed free-form surfaces without control points. Such imaging situation can occur, for example, during photogrammetric car crash test recordings where onboard high-speed stereo cameras are used to measure 3D surfaces. As a result of such measurements 3D point clouds of deformed surfaces are generated for a complete stereo sequence. The first objective of this research focusses on the development and investigation of methods for the detection of corresponding spatial and temporal tie points within the stereo image sequences (by stereo image matching and 3D point tracking) that are robust enough for a reliable handling of occlusions and other disturbances that may occur. The second objective of this research is the analysis of object deformations in order to detect stable areas (congruence analysis). For this purpose a RANSAC-based method for congruence analysis has been developed. This process is based on the sequential transformation of randomly selected point groups from one epoch to another by using a 3D similarity transformation. The paper gives a detailed description of the congruence analysis. The approach has been tested successfully on synthetic and real image data.
Three-dimensional imaging of hold baggage for airport security
Authors: Kolokytha S. , Speller R. , Robson S.
Published: June 2014

Abstract. This study describes a cost-effective check-in baggage screening system, based on "on-belt tomosynthesis" (ObT) and close-range photogrammetry, that is designed to address the limitations of the most common system used, conventional projection radiography. The latter's limitations can lead to loss of information and an increase in baggage handling time, as baggage is manually searched or screened with more advanced systems. This project proposes a system that overcomes such limitations creating a cost-effective automated pseudo-3D imaging system, by combining x-ray and optical imaging to form digital tomograms. Tomographic reconstruction requires a knowledge of the change in geometry between multiple x-ray views of a common object. This is uniquely achieved using a close range photogrammetric system based on a small network of web-cameras. This paper presents the recent developments of the ObT system and describes recent findings of the photogrammetric system implementation. Based on these positive results, future work on the advancement of the ObT system as a cost-effective pseudo-3D imaging of hold baggage for airport security is proposed.
Semi-automatic extraction of sectional view from point clouds – The case of Ottmarsheim's abbey-church
Authors: Landes T. , Bidino S. , Guild R.
Published: June 2014

Abstract. Today, elevations or sectional views of buildings are often produced from terrestrial laser scanning. However, due to the amount of data to process and because usually 2D maps are required by customers, the 3D point cloud is often degraded into 2D slices. In a sectional view, not only the portions of the objet which are intersected by the cutting plane but also edges and contours of other parts of the object which are visible behind the cutting plane are represented. To avoid the tedious manual drawing, the aim of this work is to propose a semi-automatic approach for creating sectional views by point cloud processing. The extraction of sectional views requires in a first step the segmentation of the point cloud into planar and non-planar entities. Since in cultural heritage buildings, arches, vaults, columns can be found, the position and the direction of the sectional view must be taken into account before contours extraction. Indeed, the edges of surfaces of revolution depend on the chosen view. The developed extraction approach is detailed based on point clouds acquired inside and outside churches. The resulting sectional view has been evaluated in a qualitative and quantitative way by comparing it with a reference sectional view made by hand. A mean deviation of 3 cm between both sections proves that the proposed approach is promising. Regarding the processing time, despite a few manual corrections, it has saved 40% of the time required for manual drawing.
Performance of parameter-domain and spatial-domain pole-like feature segmentation using single and multiple terrestrial laser scans
Authors: Lari Z. , Al-Durgham K. , Habib A.
Published: June 2014

Abstract. Terrestrial laser scanning (TLS) systems have been established as a leading tool for the acquisition of high density three-dimensional point clouds from physical objects. The collected point clouds by these systems can be utilized for a wide spectrum of object extraction, modelling, and monitoring applications. Pole-like features are among the most important objects that can be extracted from TLS data especially those acquired in urban areas and industrial sites. However, these features cannot be completely extracted and modelled using a single TLS scan due to significant local point density variations and occlusions caused by the other objects. Therefore, multiple TLS scans from different perspectives should be integrated through a registration procedure to provide a complete coverage of the pole-like features in a scene. To date, different segmentation approaches have been proposed for the extraction of pole-like features from either single or multiple-registered TLS scans. These approaches do not consider the internal characteristics of a TLS point cloud (local point density variations and noise level in data) and usually suffer from computational inefficiency. To overcome these problems, two recently-developed PCA-based parameter-domain and spatial-domain approaches for the segmentation of pole-like features are introduced, in this paper. Moreover, the performance of the proposed segmentation approaches for the extraction of pole-like features from a single or multiple-registered TLS scans is investigated in this paper. The alignment of the utilized TLS scans is implemented using an Iterative Closest Projected Point (ICPP) registration procedure. Qualitative and quantitative evaluation of the extracted pole-like features from single and multiple-registered TLS scans, using both of the proposed segmentation approaches, is conducted to verify the extraction of more complete pole-like features using multipleregistered TLS scans.
A New Framework For Interactive Segmentation of Point Clouds
Authors: Liu K. , Boehm J.
Published: June 2014

Abstract. Point cloud segmentation is a fundamental problem in point processing. Segmenting a point cloud fully automatically is very challenging due to the property of point cloud as well as different requirements of distinct users. In this paper, an interactive segmentation method for point clouds is proposed. Only two strokes need to be drawn intuitively to indicate the target object and the background respectively. The draw strokes are sparse and don't necessarily cover the whole object. Given the strokes, a weighted graph is built and the segmentation is formulated as a minimization problem. The problem is solved efficiently by using the Max Flow Min Cut algorithm. In the experiments, the mobile mapping data of a city area is utilized. The resulting segmentations demonstrate the efficiency of the method that can be potentially applied for general point clouds.
Modelling the appearance of heritage metallic surfaces
Authors: MacDonald L. , Hindmarch J. , Robson S. , Terras M.
Published: June 2014

Abstract. Polished metallic surfaces exhibit a high degree of specularity, which makes them difficult to reproduce accurately. We have applied two different techniques for modelling a heritage object known as the Islamic handbag. Photogrammetric multi-view stereo enabled a dense point cloud to be extracted from a set of photographs with calibration targets, and a geometrically accurate 3D model produced. A new method based on photometric stereo from a set of images taken in an illumination dome enabled surface normals to be generated for each face of the object and its appearance to be rendered, to a high degree of visual realism, when illuminated by one or more light sources from any angles. The specularity of the reflection from the metal surface was modelled by a modified Lorentzian function.
Terrestrial scanning or digital images in inventory of monumental objects? – case study
Authors: Markiewicz J. S. , Zawieska D.
Published: June 2014

Abstract. Cultural heritage is the evidence of the past; monumental objects create the important part of the cultural heritage. Selection of a method to be applied depends on many factors, which include: the objectives of inventory, the object's volume, sumptuousness of architectural design, accessibility to the object, required terms and accuracy of works. The paper presents research and experimental works, which have been performed in the course of development of architectural documentation of elements of the external facades and interiors of the Wilanów Palace Museum in Warszawa. Point clouds, acquired from terrestrial laser scanning (Z+F 5003h) and digital images taken with Nikon D3X and Hasselblad H4D cameras were used. Advantages and disadvantages of utilisation of these technologies of measurements have been analysed with consideration of the influence of the structure and reflectance of investigated monumental surfaces on the quality of generation of photogrammetric products. The geometric quality of surfaces obtained from terrestrial laser scanning data and from point clouds resulting from digital images, have been compared.
Aerial photogrammetry procedure optimized for micro uav
Authors: Anai T. , Sasaki T. , Otani H. , Osaragi K. , Kochi N.
Published: June 2014

Abstract. This paper proposes the automatic aerial photogrammetry procedure optimized for Micro UAV that has ability of autonomous flight. The most important goal of our proposed method is the reducing the processing cost for fully automatic reconstruction of DSM from a large amount of image obtained from Micro UAV. For this goal, we have developed automatic corresponding point generation procedure using feature point tracking algorithm considering position and attitude information, which obtained from onboard GPS-IMU integrated on Micro UAV. In addition, we have developed the automatic exterior orientation and registration procedure from the automatic generated corresponding points on each image and position and attitude information from Micro UAV. Moreover, in order to reconstruct precise DSM, we have developed the area base matching process which considering edge information. In this paper, we describe processing flow of our automatic aerial photogrammetry. Moreover, the accuracy assessment is also described. Furthermore, some application of automatic reconstruction of DSM will be desired.
Point cloud-based survey for cultural heritage – An experience of integrated use of range-based and image-based technology for the San Francesco convent in Monterubbiano
Authors: Meschini A. , Petrucci E. , Rossi D. , Sicuranza F.
Published: June 2014

Abstract. The paper aims at presenting some results of a point cloud-based survey carried out through integrated methodologies based on active and passive 3D acquisition techniques for processing 3D models. This experiment is part of a research project still in progress conducted by an interdisciplinary team from the School of Architecture and Design of Ascoli Piceno and funded by the University of Camerino. We describe an experimentation conducted on the convent of San Francesco located in Monterubbiano town center (Marche, Italy). The whole complex has undergone a number of substantial changes since the year of its foundation in 1247. The survey was based on an approach blending range-based 3D data acquired by a TOF laser scanner and image-based 3D acquired using an UAV equipped with digital camera in order to survey some external parts difficult to reach with TLS. The integration of two acquisition methods aimed to define a workflow suitable to process dense 3D models from which to generate high poly and low poly 3D models useful to describe complex architectures for different purposes such as photorealistic representations, historical documentation, risk assessment analyses based on Finite Element Methods (FEM).
Radiometric Calibration of dual Sensor Camera System, a Comparison of classical and low cost Calibration
Authors: Misgaiski-Hass M. , Hieronymus J.
Published: June 2014

Abstract. Several identical dual camera systems with two different spectral sensitivities have to be calibrated radiometrically and geometrically. The aim of this project is to build up a calibration laboratory for the calibration of a set of identical cameras using low cost equipment and to compare the results to classical/professional equipment. The main goal of this paper is to demonstrate how to use a low cost, inhomogeneous LED-backlight to measure the Pixel Response Non-Uniformity (PRNU) of the investigated cameras.
Interactive Trunk Extraction from Forest Point Cloud
Authors: Mizoguchi T. , Kobayashi Y.
Published: June 2014

Abstract. For forest management or monitoring, it is required to constantly measure several parameters of each tree, such as height, diameter at breast height, and trunk volume. Terrestrial laser scanner has been used for this purpose instead of human workers to reduce time and cost for the measurement. In order to use point cloud captured by terrestrial laser scanner in the above applications, it is an important step to extract all trees or their trunks separately. For this purpose, we propose an interactive system in which a user can intuitively and efficiently extract each trunk by a simple editing on the distance image created from the point cloud. We demonstrate the effectiveness of our proposed system from various experiments.
Human Vision Pathology Diagnostics by Photogrammetrics Means
Authors: Murynin A. , Knyaz V. , Mateev I.
Published: June 2014

Abstract. One of the reasons of such vision pathology as human stereoscopic vision capability dysfunction is an asymmetry of a human face. As a rule, such dysfunctions occur as early as in the babyhood, when diagnostic methods applied for adults are ineffective. Early diagnostics and prophylaxis could help in treatment of such pathology and face 3D modeling is one of the promising ways to solve this problem.
Sensitive Analysis of Observation Model for Human Tracking Using a Stochastic Process
Authors: Nakanishi W. , Fuse T.
Published: June 2014

Abstract. This paper aims at obtaining basic knowledge about characteristics of observation models for human tracking method as a stochastic process. As human tracking in actual cases are complicated, we cannot always use the same observation models for every situation. Thus in most cases observation models are set empirically so far. In order to achieve an efficient choice of models and parameters, understanding some advantages and disadvantages of such models regarding to observation conditions is important. In this paper we conduct a sensitive analysis on some types of observation models. In particular, we obtain both colour and range information at a railway station. We prepare six predictive distributions as well as six models and parameters for both colour and range observation models. We calculate posterior distributions of each pattern, namely 36 patterns for both colour and range models. As a sensitive analysis we compare a value of a ground truth and an expected value of posteriors. We also compare variances of predictive and posterior distributions. Through this experimental results, we confirm our analysis method is efficient to obtain information about observation models. In fact, all models analysed are good in whole. One suggestive result is that colour models can deal with a predictive error in mean values, while range models in variances. Another is that under occlusions range models show a good performance.
A non-conventional procedure for the 3D modeling of WWI forts
Authors: Nocerino E. , Fiorillo F. , Minto S. , Menna F. , Remondino F.
Published: June 2014

Abstract. 2014 is the hundredth anniversary of the outbreak of the First World War (WWI) – or Great War – in Europe and a number of initiatives have been planned to commemorate the tragic event. Until 1918, the Italian Trentino – Alto Adige region was under the Austro – Hungarian Empire and represented one of the most crucial and bloody war front between the Austrian and Italian territories. The region borders were constellated of military fortresses, theatre of battles between the two opposite troops. Unfortunately, most of these military buildings are now ruined and their architectures can be hardly appreciated. The paper presents the initial results of the VAST project (VAlorizzazione Storia e Territorio – Valorization of History and Landscape), that aims to digitally reconstruct the forts located on the plateaus of Luserna, Lavarone and Folgaria. An integrated methodology has been adopted to collect and employ all possible source of information in order to derive precise and photo-realistic 3D digital representations of WWI forts.
Quasi-five point algorithm with non-linear minimization
Authors: Oda K.
Published: June 2014

Abstract. Five-point algorithm is a powerful tool for relative orientation, because it requires no initial assumption of camera position. This algorithm determines an essential matrix from five point correspondences between two calibrated cameras, but results multiple solutions and some selecting process is required. This paper proposes Quasi-Five-Point Algorithm which is non-linear solver with seed solution of 8 point algorithm. The method tries to calculate the appropriate essential matrix without selecting process among multiple solutions. It is one of non-linear approach, but tries to find an appropriate seed before non-linear calculation. Using correspondences of 3 or more additional points, seed values of the solution is calculated. In this paper relationship between traditional parametric relative orientation and essential matrix is discussed, and after that quasi-five-point algorithm is introduced.