bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Optimal Excavating Trajectory of Large Mining Shovel
Authors: Lin Gui Yu , Han Hong Zheng , Zhao Jun , Li Ai Feng
Published: June 2014

Excavating trajectory impact the production efficiency and overall performance of excavator directly [1]. Hence, it’s of very realistic significance to obtain the optimal excavating trajectory. Based on site test data, the point of tangency of the rack pitch line of the bucket rod and the pitch circle of the crowd gear were determined as the rotating center and the dynamic model of working mechanism was derived; due to the change law of the current and voltage of the hoist motor, the excavating process sections was separated from the excavating trajectory; log spiral model was chosen as the fitting function, and according to the following three judgment rules: maximizing soil volume in bucket, rationalizing the excavating time and minimizing the energy consumption of unit mass of soil in bucket, the optimal excavating trajectory was obtained and provided basis for the operation and design of the large mining excavator [2].
Simulation of Motion Trajectory of Parachute Inflation Process
Authors: Tian Jia Lin , He Yun , Chen Lei , Wang Ban
Published: June 2014

Motion trajectory is the fundamental basis for the design and research of parachute. The fall state, the minimum safe altitude and airborne site are closely associated with the motion trajectory. Particularly due to rapid changes in these parameters such as canopy shape, velocity, dynamic load of the parachute, it is very difficult to determine the motion trajectory of parachute inflation process. Currently, the trajectory is mainly obtained by airdrop tests or wind tunnel tests. The tests are very expensive. Based on the force analysis and mathematical model of a certain type of parachute, we used the computer system to study the motion trajectory of parachute.
Research on Parameter Optimization Method of an Air Vehicle Gliding Trajectory
Authors: Wang Fang Peng , Xu Yong , Li Chun Ying
Published: June 2014

A mathematical model of air vehicle gliding trajectory was established and attack angle was regarded as control variable. Adaptive simulated annealing algorithm was adopted to optimize the 101 nodes of attack angle. By optimizing the control law of attack angle of gliding trajectory, the maximum range of air vehicle is increased significantly, which increases 107%.
Design and Motion Simulation of the Clamping Mechanism of Micro-Structure Injection Molding Machine
Authors: Chou Bai Ge , Cai Heng Zhi , Zhou Gang , Zhang Ya Jun , Zhuang Jian
Published: June 2014

Micro-structure injection molding machine is mainly used for processing the plastic products in micron-size or with micro-structures. This paper focuses on the design and control of the clamping mechanism of micro-structure injection molding machine. Firstly, the deformation of the clamping mechanism was analyzed. The simulation results shows that the clamping force is 5.0051×105N, and it’s bigger than the design value 500kN. Secondly, the kinetic characteristic of the clamping was simulated by ADAMS software. The curves of the displacement, velocity, clamping force of moving platen were analyzed. Thirdly, the control model of clamping mechanism was established. And the LQR controller was designed and simulated by Matlab. The rise time is 0.010s, the settling time is 0.026s and the steady-state is 0.307m.
Experiment for Vibration Suppression Based on Particle Damping for Gear Transmission
Authors: Xiao Wang Qiang , Li Wei
Published: June 2014

Introducing the particle damping technology into the gear transmission will effectively reduce the vibration during gear engagement, especially suitable for high temperature, oil-lubricating environment for the gear transmission system. In the real working situation, centrifugal load will make the particle at one end away from the rotation center. The vibration suppression of particle damping in the gear transmission is studied through experimental method. The effect of rotation speed and particle filling rate on vibration suppression of particle damping is analyzed in gear transmission. The result will provide exact theory basis and design principle for the vibration suppression of gear transmission.
Modal Test for Response Amplitude Operator of a Deepwater Semi-Submersible Platform
Authors: Sun Li Ping , Cai Shu Long , Kang Zhuang
Published: June 2014

Semi-submersible plays an important role in ocean oil and gas exploitation. This paper carried out a model test for motion response of a deepwater semi-submersible in regular waves with the model oriented in the head, beam and quartering directions. The results were presented as Response Amplitude Operators (RAO) of the platform. Dynamic responses measured in the model test were compared with the numerical results obtained by the software HYDROSTAR. Results show that the numerical results generally tally well with the experimental measurements. This illustrates the accuracy of the numerical results, and proves that the numerical results are reliable to be the reference of judging performance of the platform.
A Study on Effects of Gear Backlash on Differential Vibration
Authors: Xu Jin Li , Wei Peng , Huang Feng Yun , Wang Hong Jun
Published: June 2014

Based on UG and Automatic Dynamic Analysis of Mechanical System (ADAMS), the 3D model of differential was constructed and the real-time dynamic simulation of differential was achieved. The effects of gear backlash between half axle gears and planetary gears on the vibration of differential are studied. To increase the credibility of simulation results , the contact forces between half axle gears and planetary gears were calculated based on the Hertz elasticity impact theory.
Analysis of Noise of Gear Transmission System and Control
Authors: Zhang Zhong Gang , Fang Bin , Li Xiao Qing
Published: June 2014

In this paper, the noise of gear transmission system of the type, source and mechanism is summarized and analyzed. The method of noise control was put forward according to the mechanism of noise of gear system. Put forward reasonable Suggestions For gear type and material selection in the design of gear transmission system, the gear parameters, processing technology, cabinet design, gear train assembly, gear modification, the lubrication mode. For gear system optimization design has a certain guiding significance.
Study on the Influence Factors of Vibro-Acoustic Characteristics of Plate Structure Based on Series Approximation
Authors: Zhu Yong Yong , Dai Ren Wen , Gao Sheng Yao
Published: June 2014

To grip control mechanism of plate structure radiation noise, a method to calculate radiation resistance was improved based on series approximation, by which the analytical solution of acoustic features were derived. And then the effects of the mutual-modal coupling were investigated in studying vibro-acoustic characteristics of a simply supported plate. Some conclusions have been given, such as the relationship between the radiated noise level and the space-time distributing, fundamental principles and measures of altering the space-time distributing, which supplied the academic and applied foundation for noise control.
Normal Method for Tooth Surface Generation of Helical Gear
Authors: Lin Jing , Li Ru Qiong , Shen Hui
Published: June 2014

a general mathematical model for describing tooth surfaces of a helical gear. Normal vector of tooth surface are introduced to deal with the model. The tooth surface of a helical gear could be generated directly by giving two basic parameters and . It is believed that the model may provide a simple logical method for the design and manufacture of helical spur gears.
High Speed ​​Gear Parametric Modeling and Dynamic Analysis
Authors: Liu Yin Yin , Xiong Man Chen , Li Quan
Published: June 2014

In order to solve high-speed gear parametric solid modeling technology, improve the accuracy of design calculations gear, based the involute of inclined cylindrical gears tooth profile formed the basic principles, in the UG software system and through VB programming using UG’s parameter expression to modeling, constructing parameterized solid model of locomotive traction gear and the modeling of transmission. Analyzing and calculating with ADAMS software that the dynamic performance of gear system, provides the basis for speed ​​gear strength and parameter optimization.
Distribution of Indoor Air Quality under Air Conditioning Running
Authors: Liu Bao Wei
Published: June 2014

People are constantly committed to seeking new ways that energy saving ventilation can improve indoor air quality. In this paper, methods of theoretical analysis and numerical simulation combining established indoor ventilation jet crash fluid dynamics model to simulate the indoor air, thermal comfort and indoor air quality issues.
Design and Modeling of a New Reliable Handcuff Ring
Authors: Zhang Jie , Liu Chang Rui , Liu Hui
Published: June 2014

The structure of raditional handcuff is of lower reliability. Also, it is difficult to realise the easy-keeping of handcuff keys for different handcuff with different key. In this paper, a new safe handcuff ring is innovative designed adoping transplanation method. The structure of the said new ring is the combination of gear rack with ratchet and magnetic snap.The modeling and analyse of the new handcuff ring is also studied. The new designed safe ring has many distictive advantages that the traditional one do not have, including convinient, reliability, simplicity and beauty.
Type I Interferon in the Pathogenesis of Lupus
Authors: Crow Mary K.
Published: June 2014

Investigations of patients with systemic lupus erythematosus have applied insights from studies of the innate immune response to define IFN-I, with IFN-α as the dominant mediator, as central to the pathogenesis of this prototype systemic autoimmune disease. Genetic association data identify regulators of nucleic acid degradation and components of TLR-independent, endosomal TLR-dependent, and IFN-I–signaling pathways as contributors to lupus disease susceptibility. Together with a gene expression signature characterized by IFN-I–induced gene transcripts in lupus blood and tissue, those data support the conclusion that many of the immunologic and pathologic features of this disease are a consequence of a persistent self-directed immune reaction driven by IFN-I and mimicking a sustained antivirus response. This expanding knowledge of the role of IFN-I and the innate immune response suggests candidate therapeutic targets that are being tested in lupus patients.
IL-2: The First Effective Immunotherapy for Human Cancer
Authors: Rosenberg Steven A.
Published: June 2014

The ability of IL-2 to expand T cells with maintenance of functional activity has been translated into the first reproducible effective human cancer immunotherapies. The administration of IL-2 can lead to durable, complete, and apparently curative regressions in patients with metastatic melanoma and renal cancer. The growth of large numbers of tumor-infiltrating lymphocytes with in vitro anti-cancer activity in IL-2 has led to the development of cell transfer therapies that are highly effective in patients with melanoma. The genetic modification of T cells with genes encoding αβ TCRs or chimeric Ag receptors and the administration of these cells after expansion in IL-2 have extended effective cell transfer therapy to other cancer types.
Function of space in Daniel 1
Authors: Nel Marius
Published: June 2014

Daniel 1 narrates how Daniel and his friends come from Jerusalem and are appointed as officials at the royal court in Babylon. The narrative is governed by the various and significant references to space. The Jews’ loyalty towards Jerusalem and its association with the Temple and temple cult is challenged by the loyalty required from them at the Babylonian court as symbolised by the new names they receive − names associated with the Babylonian gods. The strategy they devise to retain their loyalty towards YHWH is decided by their request for a specific specific type of food. Their eating special food in contrast to the royal food set apart for the candidates, creates a space that relates to the determinative contrast between Jerusalem and Shinar. The tale in Daniel 1 is determined by references to space that allowed the Jewish readers to understand its meaning.Daniël 1 vertel hoe Daniël en sy vriende uit Jerusalem as hofamptenare in Babilon aangestel word. Die narratief word beheers deur verskeie belangrike verwysings na ruimte. Die Joodse jongmanne se lojaliteit aan Jerusalem en hulle verbintenis met die Tempel en tempelkultus, word deur die lojaliteit wat aan die koninklike hof van hulle verwag word, getoets. Dit word deur die nuwe name wat aan hulle gegee is, gedemonstreer – name wat waarskynlik met Babiloniese gode se name verband hou. Hulle strategie om aan JHWH lojaal te bly, berus op hulle versoek om ’n spesifieke soort voedsel te gebruik. Afsonderlike voedsel in teenstelling met dié van die koning, skep die ruimte waarbinne die bepalende kontras tussen Jerusalem en Sinar gehandhaaf kan word. Die vertelling in Daniël 1 word bepaal deur verwysings na ruimte, wat die Joodse leser in staat stel om die betekenis daarvan te begryp.
Differentialgeometrie im Großen
Authors: Biquard Olivier , Brendle Simon , Leeb Bernhard
Published: June 2014

The meeting continued the biannual conference series
Differentialgeometrie im Großen
at the MFO which was established in the 60’s by Klingenberg and Chern. Global Riemannian geometry with its connections to topology, geometric group theory and geometric analysis remained an important focus of the conference. Special emphasis was given to Kähler manifolds, geometric flows and singular spaces of non-positive curvature.
Mini-Workshop: New Crossroads between Mathematics and Field Theory
Authors: Brunetti Romeo , Bär Christian , Dappiaggi Claudio , Fredenhagen Klaus
Published: June 2014

In the last few years, it has been strongly emphasized the need to use new mathematical tools and structures which are not part of the traditional pool of expertise of the community working on the analysis of the mathematical and structural properties of classical and quantum field theory. Goal of the workshop has been to bring together some of the major experts in these topics to discuss the latest results and the new insights brought to field theory by techniques, such as microlocal analysis, infinite dimensional geometry and homological algebra.
Group Theory, Measure, and Asymptotic Invariants
Authors: Abért Miklós , Gaboriau Damien , Thom Andreas
Published: June 2014

The workshop ‘Group Theory, Measure, and Asymptotic Invariants’ organized by Miklos Abert (Budapest), Damien Gaboriau (Lyon) and Andreas Thom (Leipzig) was held 18 - 24 August 2013. The event was a continuation of the previous Oberwolfach workshop ‘Actions and Invariants of Residually Finite Groups: Asymptotic Methods’ organized by Miklos Abert (Budapest), Damien Gaboriau (Lyon) and Fritz Grunewald (Dusseldorf) that was held September 5 - September 11, 2010. Fritz Grunewald passed away in March 2010 and Andreas Thom joined the organizing team.

The workshop aimed to study finitely generated groups and group actions using ergodic and measure theoretic methods, incorporating asymptotic invariants, such as

ℓ^2

-invariants, the rank gradient, cost, torsion growth, entropy-type invariants and invariants coming from random walks and percolation theory.

The participant body came from a wide range of areas: finite and infinite group theory, geometry, ergodic theory, graph theory, topology, probability theory, representation theory, von Neumann algebras and

\ell^2

-theory. The participants typically did not speak each other’s mathematical dialect fluently. To address this situation, the organizers asked the speakers to put a special emphasis on the first, introductory part of their talks. This aspect worked very well.

As a general rule, the organizers asked speakers to talk about specific subjects, not just any nice piece of their research. In some cases, this meant sacrificing hearing about some new results from excellent mathematicians that were further away from the workshop’s main directions.
Matrix Factorizations in Algebra, Geometry, and Physics
Authors: Buchweitz Ragnar-Olaf , Hori Kentaro , Krause Henning , Schweigert Christoph
Published: June 2014

Let

W

be a polynomial or power series in several variables, or, more generally, a nonzero element in some regular commutative ring. A matrix factorization of

W

consists of a pair of square matrices

X

and

Y

of the same size, with entries in the given ring, such that the matrix product

XY

is

W

multiplied by the identity matrix. For example, if

X

is a matrix whose determinant is

W

and

Y

is its adjoint matrix, then

(X, Y)

is a matrix factorization of

W

.

Such matrix factorizations are nowadays ubiquitous in several different fields in physics and mathematics, including String Theory, Commutative Algebra, Algebraic Geometry, both in its classical and its noncommutative version, Singularity Theory, Representation Theory, Topology, there in particular in Knot Theory.

The workshop has brought together leading researchers and young colleagues from the various input fields; it was the first workshop on this topic in Oberwolfach. For some leading researchers from neighboring fields, this was their first visit to Oberwolfach.
High-Resolution Mathematical and Numerical Analysis of Involution-Constrained PDEs
Authors: Després Bruno , Dumbser Michael , Kamm James R. , Torrilhon Manuel
Published: June 2014

Partial differential equations constrained by involutions provide the highest fidelity mathematical models for a large number of complex physical systems of fundamental interest in critical scientific and technological disciplines. The applications described by these models include electromagnetics, continuum dynamics of solid media, and general relativity. This workshop brought together pure and applied mathematicians to discuss current research that cuts across these various disciplines’ boundaries. The presented material illuminated fundamental issues as well as evolving theoretical and algorithmic approaches for PDEs with involutions. The scope of the material covered was broad, and the discussions conducted during the workshop were lively and far-reaching.
A voxel-based technique to estimate the volume of trees from terrestrial laser scanner data
Authors: Bienert A. , Hess C. , Maas H.-G. , von Oheimb G.
Published: June 2014

Abstract. The precise determination of the volume of standing trees is very important for ecological and economical considerations in forestry. If terrestrial laser scanner data are available, a simple approach for volume determination is given by allocating points into a voxel structure and subsequently counting the filled voxels. Generally, this method will overestimate the volume. The paper presents an improved algorithm to estimate the wood volume of trees using a voxel-based method which will correct for the overestimation. After voxel space transformation, each voxel which contains points is reduced to the volume of its surrounding bounding box. In a next step, occluded (inner stem) voxels are identified by a neighbourhood analysis sweeping in the X and Y direction of each filled voxel. Finally, the wood volume of the tree is composed by the sum of the bounding box volumes of the outer voxels and the volume of all occluded inner voxels. Scan data sets from several young Norway maple trees (Acer platanoides) were used to analyse the algorithm. Therefore, the scanned trees as well as their representing point clouds were separated in different components (stem, branches) to make a meaningful comparison. Two reference measurements were performed for validation: A direct wood volume measurement by placing the tree components into a water tank, and a frustum calculation of small trunk segments by measuring the radii along the trunk. Overall, the results show slightly underestimated volumes (–0.3% for a probe of 13 trees) with a RMSE of 11.6% for the individual tree volume calculated with the new approach.
Analysis and correction of the dependency between laser scanner intensity values and range
Authors: Blaskow R. , Schneider D.
Published: June 2014

Abstract. Intensity values, which are registered by a terrestrial laser scanner system (TLS) for each point of a 3D point cloud in addition to its coordinates, are affected by the characteristic of the measured object and the parameters of the environment. The backscattered electromagnetic signal is influenced in his strength by the reflectivity of the scanned object surface, the incidence angle, the distance between laser scanner and object and the atmospheric respectively system specific setting of the TLS-measurement. The entity of all influences on the signal can be summarized in the laser range equation of Jelalian1. For the investigations of this study the named influences where divided into two groups. Group 1 includes the surface specific influences. The second group contains all other influences. The correction of the intensity values from the effects of group 2 theoretically allows the determination of similar materials, using similar intensity values in laser scanner point clouds. In this paper the dependency between laser scanner intensity values and range are investigated on the basis of laser scanner data recorded with a Riegl LMS-Z420i. The results are compared with data from the phase-difference laser scanner Zoller+Fröhlich Imager 5006i.
A new Gis-based map of villa Adriana, a multimedia guide for ancient paths
Authors: Canciani M. , Chiappetta F. , Michelini M , Pallottino E. , Saccone M. , Scortecci A
Published: June 2014

Abstract. For the last fifteen years the Faculty of Architecture at the University of Roma Tre, has been working on the famous Villa Adriana in Tivoli, studying its ruins and its ancient paths, in order to better understand how the villa was originally laid out. In this paper, we will talk about one of these studies, which reconnect previous works and creates a new GIS based map of Villa Adriana. The goal of this study is to create a cultural heritage evaluation. In order to achieve this aim, we have created a multimedia guide with text, drawings, 3D reconstructions and augmented reality. This work can be summarized in five steps; first of all, a new georeferenced plan was created. This drawing is based on an orthophoto and brings together all existing surveys (from historical drawings to recent surveys). In this new work we show the current status of the ruins and the original layout of Villa Adriana according to the most recent study. The second step was a 3D survey, with extensive use of photogrammetry to verify and upgrade drawings. The next and third step involved creating the Database, within which to store, edit, analyze, share, and display linked data relating to both ancient and contemporary buildings and pathways. This GIS is based on the new plan and gathers together different orders of information: original function, paving, the old paths of each original user (Hadrian, his wife Sabina, the retinue, guests and servants) as well as the ancient system of underground tunnels. It collects all the existing data relating to Villa Adriana relevant to solving the "what/where" question. The fourth step was to create a complete 3D model of Villa Adriana. The 3D reconstruction started from the existing surveys, the documentation of recent excavation and the input of the hypothetical reconstruction of lost or buried buildings. Finally we created a multimedia guide, based on a mobile app, which took information from the database to show, in real time, during the tour, where you are and what you can see around you. With this app it's possible to read information about the villa's original layout, or you can access information about the ancient users (their lives and paths). You can also see 3D reconstructions of the buildings around you.
Geometric Modelling of Octagonal Lamp Poles
Authors: Chan T. O. , Lichti D. D.
Published: June 2014

Abstract. Lamp poles are one of the most abundant highway and community components in modern cities. Their supporting parts are primarily tapered octagonal cones specifically designed for wind resistance. The geometry and the positions of the lamp poles are important information for various applications. For example, they are important to monitoring deformation of aged lamp poles, maintaining an efficient highway GIS system, and also facilitating possible feature-based calibration of mobile LiDAR systems. In this paper, we present a novel geometric model for octagonal lamp poles. The model consists of seven parameters in which a rotation about the z-axis is included, and points are constrained by the trigonometric property of 2D octagons after applying the rotations. For the geometric fitting of the lamp pole point cloud captured by a terrestrial LiDAR, accurate initial parameter values are essential. They can be estimated by first fitting the points to a circular cone model and this is followed by some basic point cloud processing techniques. The model was verified by fitting both simulated and real data. The real data includes several lamp pole point clouds captured by: (1) Faro Focus 3D and (2) Velodyne HDL-32E. The fitting results using the proposed model are promising, and up to 2.9 mm improvement in fitting accuracy was realized for the real lamp pole point clouds compared to using the conventional circular cone model. The overall result suggests that the proposed model is appropriate and rigorous.
Water Surface and Velocity Measurement-River and Flume
Authors: Chandler J. H. , Ferreira E. , Wackrow R. , Shiono K.
Published: June 2014

Abstract. Understanding the flow of water in natural watercourses has become increasingly important as climate change increases the incidence of extreme rainfall events which cause flooding. Vegetation in rivers and streams reduce water conveyance and natural vegetation plays a critical role in flood events which needs to be understood more fully. A funded project at Loughborough University is therefore examining the influence of vegetation upon water flow, requiring measurement of both the 3-D water surface and flow velocities. Experimental work therefore requires the measurement of water surface morphology and velocity (i.e. speed and direction) in a controlled laboratory environment using a flume but also needs to be adaptable to work in a real river. Measuring the 3D topographic characteristics and velocity field of a flowing water surface is difficult and the purpose of this paper is to describe recent experimental work to achieve this. After reviewing past work in this area, the use of close range digital photogrammetry for capturing both the 3D water surface and surface velocity is described. The selected approach uses either two or three synchronised digital SLR cameras in combination with PhotoModeler for data processing, a commercial close range photogrammetric package. One critical aspect is the selection and distribution of appropriate floating marker points, which are critical if automated and appropriate measurement methods are to be used. Two distinct targeting approaches are available: either large and distinct specific floating markers or some fine material capable of providing appropriate texture. Initial work described in this paper uses specific marker points, which also provide the potential measuring surface velocity. The paper demonstrates that a high degree of measurement and marking automation is possible in a flume environment, where lighting influences can be highly controlled. When applied to a real river it is apparent that only lower degrees of automation are practicable. The study has demonstrated that although some automation is possible for point measurement, point matching needs to be manually guided in a natural environment where lighting cannot be controlled.
Evaluation Of Mass Market Devices For The Documentation Of The Cultural Heritage
Authors: Aicardi I. , Lingua A. , Piras M.
Published: June 2014

Abstract. The cultural and artistic heritage has always been at the center of activities aimed at its preservation and enhancement. Italy is a country particularly rich in terms of heritage to be protected, where the high-risk due to natural hazard, as earthquakes, landslides and floods, which are adds to human activities, contribute to make the heritage more frail, land needs to be safeguarded and enhanced and new mass market technology can be considered as innovative tools for the documentation of cultural heritage. In order to increase our country on the artistic point of view, it must be known in an historical and cultural way. Moreover, it is important also to define the cultural heritage on metric terms, to be able to describe and represent it with the best approach, with the purpose to offer to the people who comes to visit our beautiful country, the reliable model of some important object, that is no longer in exposition. The possibility to use the mass-market devices can allow us to realize it, because they are available for the greater part of the visitors, in a photogrammetric way to reconstruct our models. In the last years, these devices have been very improved and the embedded sensors are becoming more and more efficient in terms of precision and reliability. Also several small video cameras are now used to document our travels and activities and to share them through Internet. In this scenario, the aim of this research is to study and validate the possibility to use mass-market technology for this purpose, testing four different devices (smartphones and video cameras) for the documentation of the cultural heritage.
3D models mapping optimization through an integrated parameterization approach: cases studies from Ravenna
Authors: Cipriani L. , Fantini F. , Bertacchi S.
Published: June 2014

Abstract. Image-based modelling tools based on SfM algorithms gained great popularity since several software houses provided applications able to achieve 3D textured models easily and automatically. The aim of this paper is to point out the importance of controlling models parameterization process, considering that automatic solutions included in these modelling tools can produce poor results in terms of texture utilization. In order to achieve a better quality of textured models from image-based modelling applications, this research presents a series of practical strategies aimed at providing a better balance between geometric resolution of models from passive sensors and their corresponding (u,v) map reference systems. This aspect is essential for the achievement of a high-quality 3D representation, since "apparent colour" is a fundamental aspect in the field of Cultural Heritage documentation. Complex meshes without native parameterization have to be "flatten" or "unwrapped" in the (u,v) parameter space, with the main objective to be mapped with a single image. This result can be obtained by using two different strategies: the former automatic and faster, while the latter manual and time-consuming. Reverse modelling applications provide automatic solutions based on splitting the models by means of different algorithms, that produce a sort of "atlas" of the original model in the parameter space, in many instances not adequate and negatively affecting the overall quality of representation. Using in synergy different solutions, ranging from semantic aware modelling techniques to quad-dominant meshes achieved using retopology tools, it is possible to obtain a complete control of the parameterization process.
Image-based 3D modeling for the knowledge and the representation of archaeological dig and pottery: Sant'Omobono and Sarno project's strategies
Authors: Gianolio S. , Mermati F. , Genovese G.
Published: June 2014

Abstract. This paper presents a "standard" method that is being developed by ARESlab of Rome's La Sapienza University for the documentation and the representation of the archaeological artifacts and structures through automatic photogrammetry software. The image-based 3D modeling technique was applied in two projects: in Sarno and in Rome. The first is a small city in Campania region along Via Popilia, known as the ancient way from Capua to Rhegion. The interest in this city is based on the recovery of over 2100 tombs from local necropolis that contained more than 100.000 artifacts collected in "Museo Nazionale Archeologico della Valle del Sarno". In Rome the project regards the archaeological area of Insula Volusiana placed in Forum Boarium close to Sant'Omobono sacred area. During the studies photographs were taken by Canon EOS 5D Mark II and Canon EOS 600D cameras. 3D model and meshes were created in Photoscan software. The TOF-CW Z+F IMAGER® 5006h laser scanner is used to dense data collection of archaeological area of Rome and to make a metric comparison between range-based and image-based techniques. In these projects the IBM as a low-cost technique proved to be a high accuracy improvement if planned correctly and it shown also how it helps to obtain a relief of complex strata and architectures compared to traditional manual documentation methods (e.g. two-dimensional drawings). The multidimensional recording can be used for future studies of the archaeological heritage, especially for the "destructive" character of an excavation. The presented methodology is suitable for the 3D registration and the accuracy of the methodology improved also the scientific value.
Cultural Heritage: An example of graphical documentation with automated photogrammetric systems
Authors: Giuliano M. G.
Published: June 2014

Abstract. In the field of Cultural Heritage, the use of automated photogrammetric systems, based on Structure from Motion techniques (SfM), is widely used, in particular for the study and for the documentation of the ancient ruins. This work has been carried out during the PhD cycle that was produced the "Carta Archeologica del territorio intorno al monte Massico". The study suggests the archeological documentation of the mausoleum "Torre del Ballerino" placed in the south-west area of Falciano del Massico, along the Via Appia. The graphic documentation has been achieved by using photogrammetric system (Image Based Modeling) and by the classical survey with total station, Nikon Nivo C. The data acquisition was carried out through digital camera Canon EOS 5D Mark II with Canon EF 17–40 mm f/4L USM @ 20 mm with images snapped in RAW and corrected in Adobe Lightroom. During the data processing, the camera calibration and orientation was carried out by the software Agisoft Photoscans and the final result has allowed to achieve a scaled 3D model of the monument, imported in software MeshLab for the different view. Three orthophotos in jpg format were extracted by the model, and then were imported in AutoCAD obtaining façade’s surveys.
Evaluating the geometric shape of a flying paraglider
Authors: Hanke K. , Schenk S.
Published: June 2014

Abstract. This paper describes the photogrammetric approach to find the geometric shape of a paraglider. As its geometry is only available during the flight this had to be done under special conditions. The layout of the camera positions was limited by the strict safety of the pilot as well as a wind and flying situation that guarantees a stable geometry of the object for several minutes. The data acquisition was finally carried out in the area of Lake Garda and the pilot had the challenging task to handle the calibrated camera using a telescope arm in predefined positions during his flight. The evaluation of the 3D position of selected discrete points representing the paraglider's shape was done by employing a bundle adjustment software and led to very satisfying results which were also proof of the stability of the paraglider during data acquisition as well as of the symmetry of the resulting shape.
Investigation on the Automatic Geo-Referencing of Archaeological UAV Photographs by Correlation with Pre-Existing Ortho-Photos
Authors: Karel W. , Doneus M. , Briese C. , Verhoeven G. , Pfeifer N.
Published: June 2014

Abstract. We present a method for the automatic geo-referencing of archaeological photographs captured aboard unmanned aerial vehicles (UAVs), termed UPs. We do so by help of pre-existing ortho-photo maps (OPMs) and digital surface models (DSMs). Typically, these pre-existing data sets are based on data that were captured at a widely different point in time. This renders the detection (and hence the matching) of homologous feature points in the UPs and OPMs infeasible mainly due to temporal variations of vegetation and illumination. Facing this difficulty, we opt for the normalized cross correlation coefficient of perspectively transformed image patches as the measure of image similarity. Applying a threshold to this measure, we detect candidates for homologous image points, resulting in a distinctive, but computationally intensive method. In order to lower computation times, we reduce the dimensionality and extents of the search space by making use of a priori knowledge of the data sets. By assigning terrain heights interpolated in the DSM to the image points found in the OPM, we generate control points. We introduce respective observations into a bundle block, from which gross errors i.e. false matches are eliminated during its robust adjustment. A test of our approach on a UAV image data set demonstrates its potential and raises hope to successfully process large image archives.
Finding the next-best scanner position for as-built modeling of piping systems
Authors: Kawashima K. , Yamanishi S. , Kanai S. , Date H.
Published: June 2014

Abstract. Renovation of plant equipment of petroleum refineries or chemical factories have recently been frequent, and the demand for 3D asbuilt modelling of piping systems is increasing rapidly. Terrestrial laser scanners are used very often in the measurement for as-built modelling. However, the tangled structures of the piping systems results in complex occluded areas, and these areas must be captured from different scanner positions. For efficient and exhaustive measurement of the piping system, the scanner should be placed at optimum positions where the occluded parts of the piping system are captured as much as possible in less scans. However, this "nextbest" scanner positions are usually determined by experienced operators, and there is no guarantee that these positions fulfil the optimum condition. Therefore, this paper proposes a computer-aided method of the optimal sequential view planning for object recognition in plant piping systems using a terrestrial laser scanner. In the method, a sequence of next-best positions of a terrestrial laser scanner specialized for as-built modelling of piping systems can be found without any a priori information of piping objects. Different from the conventional approaches for the next-best-view (NBV) problem, in the proposed method, piping objects in the measured point clouds are recognized right after an every scan, local occluded spaces occupied by the unseen piping systems are then estimated, and the best scanner position can be found so as to minimize these local occluded spaces. The simulation results show that our proposed method outperforms a conventional approach in recognition accuracy, efficiency and computational time.
3D Modeling By Consolidation Of Independent Geometries Extracted From Point Clouds – The Case Of The Modeling Of The Turckheim's Chapel (Alsace, France)
Authors: Koehl M. , Fabre Ph. , Schlussel B.
Published: June 2014

Abstract. Turckheim is a small town located in Alsace, north-east of France. In the heart of the Alsatian vineyard, this city has many historical monuments including its old church. To understand the effectiveness of the project described in this paper, it is important to have a look at the history of this church. Indeed there are many historical events that explain its renovation and even its partial reconstruction. The first mention of a christian sanctuary in Turckheim dates back to 898. It will be replaced in the 12th century by a roman church (chapel), which subsists today as the bell tower. Touched by a lightning in 1661, the tower then was enhanced. In 1736, it was repaired following damage sustained in a tornado. In 1791, the town installs an organ to the church. Last milestone, the church is destroyed by fire in 1978. The organ, like the heart of the church will then have to be again restored (1983) with a simplified architecture. From this heavy and rich past, it unfortunately and as it is often the case, remains only very few documents and information available apart from facts stated in some sporadic writings. And with regard to the geometry, the positioning, the physical characteristics of the initial building, there are very little indication. Some assumptions of positions and right-of-way were well issued by different historians or archaeologists. The acquisition and 3D modeling project must therefore provide the current state of the edifice to serve as the basis of new investigations and for the generation of new hypotheses on the locations and historical shapes of this church and its original chapel (Fig. 1)
An autonomous image based approach for detecting glacial lake outburst floods
Authors: Koschitzki R. , Schwalbe E. , Maas H.-G.
Published: June 2014

Abstract. The potential danger caused by glacier margin lakes and the related risk of glacier lake outburst floods (GLOF) increases constantly due to glaciers retreating in many parts of the world. Reasons for this development are on the one hand the new formation and enlargement of glacier margin lakes due to melt water. On the other hand, retreating and thinning glacier tongues lead to a decrease of the back pressure against the dammed glacier lakes. The paper describes the design of a photogrammetric GLOF monitoring system, based on monoscopic image sequence analysis for automatic detection of water level changes. The presented approach for measuring the water line in an image sequence is based on directional edge detection in LoG-filtered image data. After that, the water level is determined by a transformation of image measurements into object space based on orientation parameters of the camera and a geo-referenced lake basin model. The model can for instance be determined by photogrammetric methods after a GLOF; it may also be determined portion-wise by analysing shore lines at various water levels. Camera orientation parameters are determined by a local GPS-supported photogrammetric network. Comparing the determined water level changes with reference data provided by a water gauge, the precision is estimated in the order of one decimetre. A major challenge is the automatic detection of the water line in image sequences under varying light and visibility conditions. The paper will also discuss promising approaches such as multispectral images as well as a statistical analysis of grey value changes over short image sequences to eliminate disturbing reflections on the rough water surface.
Eccentricity in Images of Circular and Spherical Targets and its Impact to 3D Object Reconstruction
Authors: Luhmann T.
Published: June 2014

Abstract. This paper discusses a feature of projective geometry which causes eccentricity in the image measurement of circular and spherical targets. While it is commonly known that flat circular targets can have a significant displacement of the elliptical image centre with respect to the true imaged circle centre, it can also be shown that the a similar effect exists for spherical targets. Both types of targets are imaged with an elliptical contour. As a result, if measurement methods based on ellipses are used to detect the target (e.g. best-fit ellipses), the calculated ellipse centre does not correspond to the desired target centre in 3D space. This paper firstly discusses the use and measurement of circular and spherical targets. It then describes the geometrical projection model in order to demonstrate the eccentricity in image space. Based on numerical simulations, the eccentricity in the image is further quantified and investigated. Finally, the resulting effect in 3D space is estimated for stereo and multi-image intersections. It can be stated that the eccentricity is larger than usually assumed, and must be compensated for high-accuracy applications. Spherical targets do not show better results than circular targets. The paper is an updated version of Luhmann (2014) new experimental investigations on the effect of length measurement errors.
Photogrammetry applied to Problematic artefacts
Authors: Nicolae C. , Nocerino E. , Menna F. , Remondino F.
Published: June 2014

Abstract. The process of creating 3D accurate and faithful textured models from 2D images has been a major endeavor within the cultural heritage field. This field has general requirements, such as accuracy, portability and costs, that are often integrated by more specific needs such as the integration of color information. The aim of this paper is to show how photogrammetry can be a valid and reliable techniques for creating 3D models of museum artefacts even in case of objects with materials featuring difficult optical properties (absorptivity, reflectivity, scattering), challenging texture and complex shape/geometry. The main objective is to establish some core specifications for data acquisition and modeling, in order to guarantee the scientific quality of data and the interoperability of 3D models with the archaeologists and conservators. All these aspects are taken into consideration and presented with three study cases (two statues – one made of marble and one made of bronze – and a restored ceramic jug). The established, comprehensive and accessible pipeline for the creation of complex artefacts 3D models in the field of cultural heritage is presented and discussed.
Accuracy of typical photogrammetric networks in cultural heritage 3D modeling projects
Authors: Nocerino E. , Menna F. , Remondino F.
Published: June 2014

Abstract. The easy generation of 3D geometries (point clouds or polygonal models) with fully automated image-based methods poses nontrivial problems on how to check a posteriori the quality of the achieved results. Clear statements and procedures on how to plan the camera network, execute the survey and use automatic tools to achieve the prefixed requirements are still an open issue. Although such issues had been discussed and solved some years ago, the importance of camera network geometry is today often underestimated or neglected in the cultural heritage field. In this paper different camera network geometries, with normal and convergent images, are analyzed and the accuracy of the produced results are compared to ground truth measurements.
Evaluation of feature-based methods for automated network orientation
Authors: Apollonio F.I. , Ballabeni A. , Gaiani M. , Remondino F.
Published: June 2014

Abstract. Every day new tools and algorithms for automated image processing and 3D reconstruction purposes become available, giving the possibility to process large networks of unoriented and markerless images, delivering sparse 3D point clouds at reasonable processing time. In this paper we evaluate some feature-based methods used to automatically extract the tie points necessary for calibration and orientation procedures, in order to better understand their performances for 3D reconstruction purposes. The performed tests – based on the analysis of the SIFT algorithm and its most used variants – processed some datasets and analysed various interesting parameters and outcomes (e.g. number of oriented cameras, average rays per 3D points, average intersection angles per 3D points, theoretical precision of the computed 3D object coordinates, etc.).