bluuebunny/crossref_metadata_2025 huggingface dataset:
Deformation Monitoring in North Bohemia by Method of Permanent Scatterers
Authors: Knechtlová Barbora  , Halounová Lena  , Hlaváčová Ivana
Published: February 2025

North Bohemia Brown Coal Basin is a mining area which has been exploited since medieval period. The brown coal mines are both underground, and open-cast. Deep mines were active till the 20thcentury and their surface layer is stabilized. The region is covered by historical open mines (20thcentury) and still active open-pit mines. Their activities are always accompanied by landscape and morphology changes during and after the mining period. Large areas of closed open mines are reclaimed to forests, lakes, agriculture fields, etc. These are not only mines as they include also dumps covering vast regions. They even seem to be more sensitive to further Earth surface consolidation causing of landslides and subsidence. These ground surface movements can have a serious impact on constructions built in the places and therefore the region needs to be monitored. In addition to classical levelling methods, new methods are being used for detection of potentially dangerous areas. One of the methods is radar interferometry. It allows for Earth-crust deformation mapping with the use of satellite images, without the necessity of expensive on-site measurements. Its accuracy may even reach several mm/yr in the theoretical case. This method is usable in areas with no vegetation and for objects, which are not expected to change their spectral characteristics during monitoring. This applies to artificial objects (buildings, roads, railways), which are of most interest to public (centres of villages, cultural monuments, communications and industrial areas). A significant limitation of standard InSAR processing is the impact of atmosphere, which shows strong spatial correlation and is uncorrelated in time, whereas target motion is usually correlated in time. Therefore the method of Permanent Scatterers is used in order to deal with this atmospheric effect. To improve the method, corner reflectors are installed in the neighbourhood of the area of interest. They are in village centres, next to cultural monuments, water reservoirs and in industrial and mining areas.
Monitoring the Urban Expansion of North-Western Athens due to the Olympic Games Using Multitemporal Satellite Data and GIS Techniques
Authors: Nikolakopoulos Konstantinos G.  , Tsombos Panagiotis I.
Published: February 2025

The aim of this study was to detect and map all the changes that occurred in North-Western Athens due to the 2004 Olympic Games, estimate the urban expansion rate and the human interferences in the natural landscape, using remote sensing data and GIS techniques. Multitemporal and multiresolution satellite data and topographic maps of 1:5.000 scale were used for the urban growth mapping. The spatial resolution of all the satellite images ranges from 5 to 15 meters. The Corine Land Cover 2000 classification was also used in order to detect possible changes to the land uses. Finally the qualitative and quantitative results of this study are presented in this paper.
Solar Surface Irradiance from New Meteorological Satellite Data
Authors: Oumbe Armel  , Blanc Philippe  , Schroedter-Homscheidt Marion  , Wald Lucien
Published: February 2025

This paper presents the first prototype of a new method, for assessing solar surface irradiance, benefiting from advanced products derived from recent Earth Observation missions. This method -called Heliosat-4- is based on the radiative transfer model libRadtran and will provide direct, diffuse components and spectral distribution of solar surface irradiance every 3 km and ¼ h over Europe and Africa. The advantage of the Heliosat-4 method is the simultaneous computation of direct and diffuse irradiances. The outcomes of this prototype of Heliosat-4 method are compared to ground measurements, of direct and global irradiances, made at 4 stations in Europe and Northern Africa. The results show that standard deviation attained by the Heliosat-4 method for global irradiance is fairly similar to that attained by current methods. A significant bias is actually observed and discussed.
Probability Satellite Imagery Based Maps for Substituting Tobacco with Energy Plants
Authors: Perakis Kostas  , Faraslis Ioannis  , Rozakis Stelios  , Stathakis Demetris
Published: February 2025

The objective of this paper is to spatially delineate high production areas with respect to the artichoke energy plant, within ex-tobacco producing zones. A number of spatial factors, such as environmental, agricultural, socio-economical and cultivation-specific ones, are taken into consideration. The concurrent evaluation of these factors can only be achieved by the combination of a vast amount of diversified data, exploiting the synergy of remote sensing and geographical information systems and science. In the present study, eleven administrative units of the finest available resolution in Hellas, i.e. sub-municipal divisions (Dimotika Diamerismata), have been studied up to the year 2005 in the prefecture of Karditsa. The goal is to identify tobacco cultivating zones and subsequently produce maps of ranked suitability for the cultivation of energy plants. The exact identification of the tobacco fields based on the satellite imagery has been implemented via classification techniques as well as by the use of auxiliary data, including field surveys and digital layers (road network, hydrographic network, et.c.).The construction of ranked suitability maps for the artichoke energy plant has been achieved by the construction of the probability digital map for each factor, including altitude, slope, PH, drainage and others. The probability maps are presented in this paper along with the most interesting findings as well as direction for future research.
The Use of the Hough Transformation in Urban Remote Sensing Applications
Authors: Vozikis George
Published: February 2025

This paper investigates the outcome of building extraction techniques from optical remote sensing high-resolution data by applying Hough Transformation procedures. The proposed workflow consists of 4 major steps, namely the pre-processing of the data, nDSM (normalized Digital Surface Model) creation, building localization and building extraction. The advantages and disadvantages of this approach are discussed. The general conclusion is that the Hough Transformation is a very powerful tool for increasing the degree of automation during building extraction, while it is very robust against noisy data. Additionally the level of detail of the extracted buildings can easily be adjusted, but dark shadows in the images can make the algorithms produce erroneous results.
Relation Between Carbon Monoxide, from MOPITT, and Large Fires Emissions
Authors: Calle Abel  , Casanova José-Luis  , Sanz Julia  , Salvador Pablo  , González-Alonso Federico
Published: February 2025

This study shows the correlation between large fires emissions and Carbon Monoxide estimated by the atmospheric sensor MOPITT (Measurements of Pollution in the Troposphere) onboard Terra satellite. The zone analyzed is the Iberian Peninsula, Spain and Portugal, during the summer season. The CO is a very important trace gas produced by forest fire emissions and its role in the cycle of atmospheric carbon is very relevant. This study is focused on two main topics: the assessment of dispersion of CO emissions caused by large fires and the study of fires series and its CO emissions.
Study on Synthetic Aperture Radar Potential for Direct Biomass Assessment
Authors: Dabrowska-Zielinska Katarzyna  , Bochenek Zbigniew  , Kowalik Wanda
Published: February 2025

Earth Observation data give high potential to assess the biomass of vegetation. Initially, methods of deriving information on vegetation growth conditions and biomass were based on optical data, collected by environmental satellites with sensors of different resolutions (low and high-resolution satellite images). However due to frequent clouds cover, the application of multi-temporal SAR data proved to be very useful for classification of vegetation and application for biomass assessment. The presented paper gives an overview of the state-of-the art in the field of radar applications for vegetation studies with the special emphasis put to evaluation of biomass. Applications of different types of SAR sensors are presented for two types of vegetation relevant for biomass production: agricultural crops and forests. As far as forests are concerned, multiple approaches are presented, which apply various radar wavelengths (C-band, L-band, P-band) and different wave polarizations (VV, HH, HV). Results from regression analyses with forest variables: biomass, height, dbh (diameter-breast-height) and total stem number were demonstrated with conclusions concerning optimal choice of radar band and polarization for assessment of these variables with high accuracy. Usefulness of various radar techniques was tested, like PPD (Polarization Phased Difference), or semi-empirical algorithms based on a two layer radar backscatter model. Also applicability of special indices, useful for better assessment of forest biomass, like BCI (Biomass Consolidation Index), which is the combination of biomass density (t/ha) and stand consolidation (amount of trees per ha), was presented. Analogous analysis of recent achievements was done for SAR applications related to agricultural crops. Conclusions concerning optimal SAR wavelengths and polarizations for crop type mapping were presented, including own Author's experience in crop classification based on various SAR sensors (X and L bands). Results concerning interactions of a backscatter signal with soil and vegetation were demonstrated, with their implications on accuracy of biomass assessment. Methods incorporating multi-frequency polarimetric SAR into the crop canopy models aimed at obtaining physical parameters related to biomass, as Leaf Area Index and crop height, were discussed. Finally, the summary table, presenting possibilities of applications and ordering data from different sensors (past and present), wavelengths, polarizations, spatial resolutions for assessment of various vegetation parameters, with the special emphasis put to biomass, was created as a result of the study.
ETMS: A System for Economic Management of Overlay Traffic
Authors: Soursos Sergios  , Callejo Rodriguez María Ángeles  , Pussep Konstantin  , Racz Peter  , Spirou Spiros  , Stamoulis George D.  , Stiller Burkhard
Published: February 2025

The concept of Economic Traffic Management (ETM) encompasses various techniques for optimizing overlay networks considering both, underlay and overlay networks' performance requirements as well as the resulting economic implications for ISPs. This work presents several mechanisms through an overall ETM System (ETMS), identifying the possibility for synergies between mechanisms, both in the sense of complementarity of decision grounds and in the sense of functionality and components employed thereby. The paper describes the core ETMS architecture and how various mechanisms are instantiated. It continues with the discussion of the flexibility and modularity of this architecture, allowing for the accommodation of synergies. Finally, it presents selected results from the test-bed trials of the ETMS and a dedicated discussion on incentives behind these ETM mechanisms.
Conceptual Design and Use Cases for a FIRE Resource Federation Framework
Authors: Wahle Sebastian  , Magedanz Thomas  , Gavras Anastasius
Published: February 2025

Projects of the Future Internet Research & Experimentation (FIRE) initiative are building an experimental facility that shall serve the needs of Future Internet research and development. The main design principles are virtualization of resources and federation. Federation is a means to meet requirements from Future Internet research that cannot be met by individual testbeds. In particular, to support large scale experiments utilizing heterogeneous resources, a federation of experimental facilities is needed. While several initiatives are currently establishing large scale testbeds, the mechanisms for federating such environments across the boundaries of administrative domains are unclear. This is due to the lack of established and agreed federation models, methods, and operational procedures. In this article we propose a federation model that defines high level conceptual entities for federating resources across administrative domains. A first prototype implementation of the functional components derived from the model has been realized and evaluated. This is demonstrated by the discussion of use cases that depict the flexibility of the proposed approach. The model can guide future testbed developments and harmonize the currently scattered efforts across several FIRE projects in order to establish an agreed resource federation framework. This framework shall be the basis for Future Internet research and experimentation in Europe and provide experimental facility services to academia and industry.
Understanding Aspects of Air Transportation Systems through an Agent Based Impact Analysis
Authors: Davies G.  , Price M.  , Early J.  , Connally P.
Published: February 2025

The prediction of the behavior of complex systems remains a costly and time consuming activity due to their data intensive nature. Such dynamic systems do not always lend themselves to a quantitative behavioral analysis. An impact analysis is a novel qualitative approach aimed at determining how a system element deviates from a pre-defined “normal” operational mode due to a change in the operation of another element existing within the same architecture, or due to an interaction with an external environmental condition. This qualitatively determines the elements in the system that would be affected by a modification, and can aid in system development by identifying relationships and interdependencies prior to implementation. An agent based modeling approach is used to create the analysis tool for determining impact within the system. The paper presents an agent based impact analysis applied to a sample United Kingdom Air Traffic Management system as a means of validating the model and approach. The analysis data is validated against data collected from the real world ATM system. The results from the test case vindicated the assumptions made and also identified a number of areas for further development. The capability of impact analyses and the potential for application to complex architectures appears promising based on the results.
Sufficient scope in current aircraft technology developments?
Authors: de Haan Alexander R.C.
Published: February 2025

Air travel demand is increasing at a rate much higher than the annual economic growth. This growth has both very positive and negative effects. The increase of negative effects – such as the noise pollution and greenhouse gas emissions – might not cause problems because technologies are being developed that will compensate them. The starting point of this research is to discover whether this claim concerning the possibilities of the current aircraft technology developments is true. In other words: is the current development in aircraft technology capable to contribute to a sustainable development in the aviation sector by keeping current benefits, while mitigating the adverse effects? Existing research on this issue is mostly trend research, focussing at the average technology efficiency increase and transposing this to the future. In a context where multiple actors have to decide about what to do, this transposition is not enough. An aggregated number does not reveal the concrete options and causal relations behind it. This paper, therefore, introduces the open and explicit method of systems analysis to answer the question if (and if so, how) new aircraft technology can mitigate the adverse effects of an increasing air travel demand, while keeping the benefits. Applying the systems analysis, this paper concludes that current developments in aircraft technology are not enough to mitigate the adverse effects of growth. The combination of the efficiency improvement rate, the growth rate of the demand for air travel, and the long replacement times for older technology in our research do not proof to cancel each other out. We suggest to not only invest more into developing even better technologies, but to also search for non-technical solutions; unless we, as a society, decide that an increase in the negative consequences of aviation is less important than other (environmental) issues.
Significant Turnaround Process Variations due to Airport Characteristics
Authors: Oreschko Bernd  , Schultz Michael  , Elflein Jenny  , Fricke Hartmut
Published: February 2025

One contributor for excessive flight delays is insufficient ground operation performance with excessive process durations. Further productivity is measured not only by the airline but also by the airport operator and the ground handling companies. Collaborating in the A-CDM with other partners, the aim is to understand process characteristics and to predict process duration for the exact Gate Occupancy Time needed for operational capacity planning. Within this paper focus is set on process variations within specific sub processes for different airports, depending on their network function. An introduction of an intermediate airport category beside hub and non-hub airport is given. We found significant dependencies of turnaround characteristics depending on airport classification, especially for loading process on hub airports.
A Time-Space Diagram as Controller Support Tool for Advanced Continuous Descent Operations
Authors: de Leege A.M.P.  , in't Veld A.C.  , Mulder M.  , van Paassen M.M.
Published: February 2025

The Advanced Continuous Descent Approach improves the environmental performance of air transport, however currently at the cost of runway capacity. Air traffic controllers require support tools for early de-confliction, accurate spacing and sequencing to increase capacity for these approaches. In the transition towards the operational concepts envisioned by SESAR and NextGen aircraft systems evolve that potentially enable Advanced Continuous Descent Approaches in high-density traffic. This paper gives an overview of a research project that focuses on a controller support tool for Advanced Continuous Descent Operations using current and future aircraft systems. Basis of the tool is a Time-Space Diagram, which is commonly used to analyze transportation related problems such as traffic congestion. However, the application as an air traffic controller support tool is new. Controller-in-the-loop experiments indicated that the display supports the controller in his task and reduces controller workload significantly. The Time-Space Diagram is a separate display and causes controllers to work across multiple displays. The concept of Visual Momentum is applied for rapid data comprehension when switching between the Time-Space Diagram and the conventional Plan View Display. The Time-Space Diagram provides the controller with a ‘summary’ of task relevant information i.e. the arrival sequence, landing intervals, in-trail spacing, conflicts, aircraft proximity that is derived from air- or ground-based trajectory predictors. The task information is selectable to call up relevant views in the interface. Views on the display are coordinated to improve information integration. To support the controller in planning future actions the controller can check the effect of possible spacing techniques (e.g. speed control) on the traffic situation through either display. Controller-in-the-loop experiments are planned to evaluate the proposed controller interface. Subsequently the preliminary designs for a Time-Space Diagram as a controller support tool during Advanced-Continuous Descent Approaches relying on existing and future aircraft systems are further developed.
Direct Maintenance Cost Projection for Ageing Airbus Aircraft
Authors: Bruinsma Remko P.
Published: February 2025

The Airbus fleet is ageing and all the researches in the past agree upon the fact that there is an ageing effect for commercial aircraft with respect to the amount of maintenance to be performed. This paper constructs a model to investigate the start of ageing and the steepness of the aircraft maintenance ageing curve. For both components and the airframe are the different parameters related to ageing defined. These parameters are reviewed with respect to their impact on the amount of maintenance performed over time. For scheduled maintenance this is done by a Maintenance Planning Document extraction of the additional ageing related maintenance tasks. Unscheduled maintenance is assessed by regression analysis of the Pilot Reports, Maintenance Reports and Mean Time Between Unscheduled Removals of components.
The Use of a Dynamic solution space to Predict Air Traffic Controller Workload
Authors: d'Engelbronner J.G.  , Mulder M.  , van Paassen M.M.  , de Stigter S.  , Huisman H.
Published: February 2025

Previous research introduced the solution space as a workload metric for air traffic controller merging tasks. The solution space Diagram is a mapping of intruding aircraft trajectories to the velocity/heading plane in the form of conflict zones and safe areas. Choosing a velocity vector in either one will provide an unsafe or a safe solution, respectively. In this paper an improved, dynamic solution space will be tested for correlations with air traffic controller workload. An experiment has been conducted where subjects were required to line up all aircraft in a sector towards a certain waypoint, while continuously rating their workload. High correlations were found between several solution space parameters and the subjective workload.
Bayesian Estimation of Accident Rate, Trend and Uncertainty
Authors: Bloem Edwin A.  , Blom Henk A.P.
Published: February 2025

Aviation accident statistics provide essential information about the development of safety of air transport. They provide insight into the progress made by air transport industry and may indicate possible safety bottlenecks. Based on these insights, the aviation industry can set their strategy and priorities right. Important accident statistics are accident rate, trend and uncertainties based on recorded accident data. One established approach in jointly estimating rate and trend from accident statistics is to perform a regression analysis. However, the uncertainty is not estimated. Another established approach is not to bother about the trend, and just estimate rate and uncertainty for each year separately. This leads to rapid variations in year to year estimates. This paper overcomes the limitation of the established approaches by developing a Bayesian estimation approach for the joint estimation of accident rate, trend and uncertainty. Using worldwide statistical data on aviation accident and flights, it is demonstrated that the novel developed approach works well. Subsequently the novel approach is used to show that there is statistically significant evidence that since 2003 ground related accident rate tends to overtake lead from air related accident rate.
Aluminium in Façades
Authors: Knaack Ulrich
Published: February 2025

An overview of the status quo in the field of façade design and construction is given, related to the core aspects energy, efficiency and individuality. In a second part the research, executed by the Façade Research Group at the TU Delft is described and the relevant and influencing research topics for design decisions in architecture are described:
On Computing Backbones of Propositional Theories
Authors: Marques-Silva Joao  , Janota Mikoláš  , Lynce Inês
Published: February 2025

Backbones of propositional theories are literals that are true in every model. Backbones have been used for characterizing the hardness of decision and optimization problems. Moreover, backbones find other applications. For example, backbones are often identified during product configuration. Backbones can also improve the efficiency of solving computational problems related with propositional theories. These include model enumeration, minimal model computation and prime implicant computation. This paper investigates algorithms for computing backbones of propositional theories, emphasizing the integration of these algorithms with modern SAT solvers. Experimental results, obtained on representative problem instances, indicate that the proposed algorithms are effective in practice and can be used for computing the backbones of large propositional theories. In addition, the experimental results indicate that propositional theories can have large backbones, often representing a significant percentage of the total number of variables.
Compiling Uncertainty Away in Non-Deterministic Conformant Planning
Authors: Albore Alexandre  , Palacios Hector  , Geffner Hector
Published: February 2025

It has been shown recently that deterministic conformant planning problems can be translated into classical problems that can be solved by off-the-shelf classical planners. In this work, we aim to extend this formulation to non-deterministic conformant planning. We start with the well known observation that non-deterministic effects can be eliminated by using hidden conditions that must be introduced afresh each time a non-deterministic action is applied. This observation, however, leads to translations that have to be recomputed as the search for plans proceeds. We then introduce other translations, that while incomplete, appear to be quite effective and result in classical planning problems that need to be solved only once. A number of experimental results over existing and new domains are reported.
Automating Layouts of Sewers in Subdivisions
Authors: Burch Neil  , Holte Robert  , Müller Martin  , O'Connell David  , Schaeffer Jonathan
Published: February 2025

An important part of the creation of a housing subdivision is the design and layout of sewers underneath the road. This is a challenging cost optimization problem in a continuous threedimensional space. In this paper, heuristic-search-based techniques are proposed for tackling this problem. The result is new algorithms that can quickly find near optimal solutions that offer important reductions in the cost of design and construction.
On Ambiguity in Robot Learning from Demonstration
Authors: Bensch Suna  , Hellström Thomas
Published: February 2025

An overlooked problem in Learning From Demonstration is the ambiguity that arises, for instance, when the robot is equipped with more sensors than necessary for a certain task. Simply trying to repeat all aspects of a demonstration is seldom what the human teacher wants, and without additional information, it is hard for the robot to know which features are relevant and which should be ignored. This means that a single demonstration maps to several different behaviours the teacher might have intended. This one-to-many (or many-to-many) mapping from a demonstration (or several demonstrations) into possible intended behaviours is the ambiguity that is the topic of this paper. Ambiguity is defined as the size of the current hypothesis space. We investigate the nature of the ambiguity for different kinds of hypothesis spaces and how it is reduced by a new concept learning algorithm.
Simulating Robotic Auditory Environments
Authors: Martinson Eric
Published: February 2025

The use of ray-tracing for modeling the propagation of sound through an indoor environment has long been a mainstay of architectural acoustics. Provided accurate enough models of sound sources and the surrounding environment are available, ray-tracing can be used to predict not just volume information, but also the energy and direction of sound incident upon a receiver, and even reconstruct the wave for auralization. For mobile robots, this is important for exploring simulation work in the rapidly expanding domain of auditory perception. Given a known environment, a robot can test perception models or construct aurally dependent paths through an environment. This work evaluates the effectiveness of ray-tracing as a simulation tool through real robotic experiments, comparing the predicted sound volumes with measured data. Furthermore, this work explores using robot generated three-dimensional obstacle maps from an on-robot time-of-flight camera as part of the environment map passed to the acoustic simulator.
The Role of DInSAR Techniques in the Analysis of Ground Deformations Related to Subsidence and Landslide Phenomena
Authors: Cascini Leonardo  , Ferlisi Settimio  , Fornaro Gianfranco  , Peduto Dario
Published: February 2025

This work presents some successful applications of Differential SAR Interferometry (DInSAR) techniques to both subsidence and slow-moving landslide phenomena at different scales, also giving perspectives of future valuable developments.
A Design and Construction Database for Cut-and-cover Tunnel Maintenance Using 3D Models
Authors: Aruga Takashi  , Arai Yasushi  , Kamachi Hideya  , Oishi Keiji
Published: February 2025

Maintenance and management have become increasingly important. In particular, underground structures in urban areas such as subway tunnels require suitable maintenance. It is vital to manage specific information for maintenance and management to ensure permanent use. In this study, we focused on cut-and-cover tunnel structures. We searched wide-ranging reference materials for maintenance and management, and developed an information management system using 3D models and a database.
A Constitutive Model for Predicting Cumulative Deformation of Roadbed Filled with Silty Sands Induced by Repeated Traffic Loading
Authors: Zhang Hongbo  , Song Xiuguang  , Wand Honghong
Published: February 2025

A new computational approach with high efficiency is developed in the present paper, allowing the evaluation of the cumulative deformation of silty-sands subgrade induced by long term repeated traffic loading. It notably relies upon the formulation of a cyclic equivalent visco-plasticity model basing on shakedown theory, which describes the progressive accumulation of permanent deformations when subjected to long-term stress cycling generated by the traffic loading. The constitutive model incorporates both shear yield surfaces and volume yield surfaces, which can reflect complex deformation features with strain hardening and shear dilatancy. According to a lot of static and cyclic triaxial test results, the computational efficiency and accuracy of model is certificated.
Simulation Analysis on Inter-space Rock Strengthening Project of Ultra-small Spacing Tunnels with Large Section in Bad Rock Mass
Authors: Gong Jianwu  , Xia Caichu  , Lei Xuewen
Published: February 2025

As a new-type structure, the ultra-small spacing tunnel with large section has shown its adaptability and superiority gradually. Engineering practices indicate that the mechanical characteristic of inter-space rock is especially complicated due to the constructing impaction. By using general finite element analysis software, an elasto-plastic simulation model was established. The tunnel mechanical characteristic of inter-space rock under different strengthening projects has been researched. According to the comparison analysis of rock displacement and internal force of support respectively, some proposal of reinforcement area and construction method was put forward. In bad rock, the upper part of inter-space rock is one of the worst places of stress state, where the reinforcement should be put much emphasis on. The result shows that strengthening by advanced grouting using small duct for pre reinforcement at upper part of inter-space rock can dramatically improve the integral stability of tunnel based on conventional support. Finally, the monitoring data in practical tunnel engineering were analyzed, and the strengthening method was proved to be reasonable in weak rock. The research conclusions presented can be adopted in the design and construction of similar tunnel engineering.
SMT of Latvian, Lithuanian and Estonian Languages: a Comparative Study
Authors: Khalilov Maxim  , Pretkalniņa Lauma  , Kuvaldina Natalja  , Pereseina Veronika
Published: February 2025

This paper is an attempt to discover the main challenges in working with Baltic and Estonian languages, and to identify the most significant sources of errors generated by a SMT system trained on large-vocabulary parallel corpora from legislative domain. An immense distinction between Latvian/Lithuanian and Estonian languages causes a set of non-equivalent difficulties which we classify and compare.
Elongation-CIS method: Describing excited states of large molecular systems in regionally localized molecular orbital basis
Authors: Makowski Marcin  , Gu Feng Long  , Aoki Yuriko
Published: February 2025

The elongation methodology is extended towards description of excited states through the ab initio CIS expansions in regionally localized molecular orbital basis. The formalism and implementation of the elongation-CIS method are presented. The expected accuracy of the method in comparison to the conventional CIS approach is illustrated by the results of calculations for model systems.
Paradoxes of measures of quantum entanglement and Bell's inequality violation in two-qubit systems
Authors: Miranowicz Adam  , Horst Bohdan  , Koper Andrzej
Published: February 2025

We review some counterintuitive properties of standard measures describing quantum entanglement and violation of Bell's inequality (often referred to as “nonlocality”) in two-qubit systems. By comparing the nonlocality, negativity, concurrence, and relative entropy of entanglement, we show: (i) ambiguity in ordering states with the entanglement measures, (ii) ambiguity of robustness of entanglement in lossy systems and (iii) existence of two-qubit mixed states more entangled than pure states having the same negativity or nonlocality. To support our conclusions, we performed a Monte Carlo simulation of 106two-qubit states and calculated all the entanglement measures for them. Our demonstration of the relativity of entanglement measures implies also how desirable is to properly use an operationally-defined entanglement measure rather than to apply formally-defined standard measures. In fact, the problem of estimating the degree of entanglement of a bipartite system cannot be analyzed separately from the measurement process that changes the system and from the intended application of the generated entanglement.
Playing Games with Games
Authors: Wooldridge Michael
Published: February 2025

The past decade has been witness to a huge explosion of interest in the computational aspects of game theory. One topic that has received much attention is that of mechanism design. Crudely, mechanism design can be understood as the problem of designing games so that, if every player in the game acts rationally, certain desirable outcomes will result. In mechanism design, it is usually assumed that the designer of the mechanism has complete freedom to design a mechanism as desired. But this is not the reality of most real-world mechanism design problems: when a Government develops a new law, for example, they do not usually have a blank slate, but must work start from the framework of society as it exists. In this talk, I will present work we have done on the computational aspects of such “mechanism design for legacy systems”. In the settings we consider, a principal external to a system must try to engineer a mechanism to influence the system so that certain desirable outcomes will result from the rational action action of agents within the system. We consider two ways in which a principal might influence a system: First, through communication, which can be used to modify the beliefs of system participants, upon which players will choose actions to perform; and second, by imposing taxation schemes upon the system, so that the preferences of participants are perturbed appropriately.
Foundation design and construction for an LPG terminal in a difficult geology and constrained waterfront in coastal Lagos
Authors: Fatokun Olaposi  , Magnani Gianguido
Published: February 2025

LPG (liquefied petroleum gas or cooking gas) domestic consumption, despite the abundance of natural gas in Nigeria is still very low. Nigeria is the second most endowed nation in Africa with proven reserve of over 260 trillion cubic feet of natural gas either associated with petroleum or occurring on its own gas field, even as up to 2 million cubic feet is flared off daily as crude oil is drilled making Nigeria the largest gas flaring country in the world. The low gas consumption is a result of lack of adequate downstream LPG handling infrastructures to take bulk LPG gas from mother vessels to onshore locations where gas can be easily transported for domestic use.
Performance Comparison of Vertical-Horizontal with Conventional Reinforced Soil Walls Using Numerical Modelling
Authors: Shrestha Binod  , Khabbaz Hadi  , Fatahi Behzad
Published: February 2025

Conventional reinforced soil walls have demonstrated acceptable performance during earthquake occurrences. Nevertheless, there is still some potential for enhancing the performance of these walls without increasing the cost significantly. This paper presents an overview on the application of vertical components to the reinforced soil in addition to the horizontal reinforcement. The performance of conventional and the modified reinforced soil walls are evaluated and compared to each other. In this study, a series of 2D models is carried out using PLAXIS, finite element software, to investigate behaviour of these walls. The performance of reinforced walls is evaluated under the seismic loads of Kobe earthquake. The results indicate that the proposed wall with vertical reinforcement has superior performance compared with the conventional method and can reduce the risk of failure during earthquakes.
Using electro-osmosis technique in the improvement of a Ugandan clay soil
Authors: Kalumba Denis  , Umutoni Brenda  , Kulabako Robinah  , Glendinning Stephanie
Published: February 2025

Although electroosmotic ground improvement on fine grained soils was pioneered way back in the 1940s, and the technique has been tried in various places around the world, no single investigation of the potential of this innovative method in dewatering and stabilising soft soils has ever been attempted in Uganda. Therefore, the effect of electro-osmosis treatment on a typical Ugandan clay was undertaken. The study focused on evaluating the performance of this process on the shear strength and moisture content of the soil. The experimental study was carried out in a bench scale electroosmotic cell with dimensions: 201 mm by 102.5 mm by 90 mm. The results demonstrated that the electro-osmosis process could significantly enhance reduction of the soil water content resulting in increased soil shear strength. The quality of electroosmotic improvement was enhanced by longer processing time and increased potential gradient. However, the improvement was limited by the drying of the anode area.
The Effect of Iron Oxide on the Strength of Soil/Concrete Interface
Authors: Okonta F.  , Derrick A.
Published: February 2025

The effect of free iron oxide on the direct shear strength parameters of a weathered quartzite was investigated in a conventional shear box device with smooth and rough concrete bases. The result indicate that increase in the free iron oxide content result in increase in soil cohesion, and decrease in friction angle when sheared without soil concrete interface. The introduction of rough concrete surface result in significant scatter or weak trend in the iron oxide – cohesion/friction angle curves. However decrease in strength with increase in roughness was indicated for the mix with the highest concentration of iron oxide which may be due to the shift of the failure plane from the interface to the soil.
Geosynthetics in Road Pavement Reinforcement Applications
Authors: James Garth
Published: February 2025

geosynthetics for reinforcement of road pavements. The applications include sub-grade stabilisation and basal reinforcement where either or both of the separation and reinforcement function of the geosynthetic are fulfilled. The primary mechanisms of reinforcement in operation for sub-grade stabilisation include lateral restraint or confinement, increased bearing capacity and the tensioned membrane type support. Pavement performance and benefit from the reinforcement layer in full-scale tests are mentioned. Basal reinforcement is used for permanent paved roads and is typically applicable for low volume roads founded on weak sub-grade where the geosynthetic is placed between or within the sub-base or base layers of the pavement structure provides lateral restraint. The behaviour and benefits of geosynthetics, particularly geogrids, in these applications is mentioned. For purposes of design and specification, geosynthetic properties and the tests needed to define those properties are of great importance. Some of these properties and test methods are presented with recent innovations in geosynthetic products taking design to an approach of performance based specifications rather than the standard property based specifications.
An Alternative to the Re-drive for determining Rod Friction exerted in DPSH Testing
Authors: MacRobert Charles  , Kalumba Denis  , Beales Patrick
Published: February 2025

An uncertainty in Dynamic Probe Super Heavy (DPSH) penetration resistance values is rod friction during probing. The re-drive is a common method used in southern Africa to determine rod friction, however there is no reported use of torque readings on the rods. An investigation into the effectiveness of the two methods was carried out in a deep homogeneous sand deposit, with a shallow water table, at Capricorn in Cape Town, South Africa. The re-drive was undertaken at refusal by withdrawing the rods approximately 1 meter. The re-drive blow counts increased dramatically over the 1 meter suggesting wet sand collapsed into the void ahead of the probe. The torque readings were either taken each time a new rod was added or only once refusal had been reached. The incremental torque readings showed that the rod friction increased with depth below the water table. No great difference between single torque readings taken at refusal with those taken as part of determining the entire torque profile was found. From a comparison with SPT N values a method of determining the rod friction is suggested based on a single torque reading at refusal.
Empirical Equivalence between SPT and DPSH Penetration Resistance Values
Authors: MacRobert Charles  , Kalumba Denis  , Beales Patrick
Published: February 2025

It is often necessary to determine design parameters from Dynamic Probe Super Heavy n values with correlations based on Standard Penetration Test N values. This is often done by assuming equivalence, as both tests use the same drive energy. In this study, an empirical equivalence was developed in sandy material from different geological depositional and weathering environments. Data collected from previous geotechnical investigations from across southern Africa was analysed. It was apparent that energy losses were greater in the DPSH test than in the SPT, leading to higher resistance values in the former. The SPT is carried out within a borehole whereas the DPSH is continuously percussed into the soil. The dynamic whipping of the DPSH causes soil to fill the small air annulus around the rods exerting a frictional resistance. The different geological settings of the test sites revealed that although various factors impact friction differently, the equivalence varied in a similar manner. Hence an empirical equivalence function is suggested to determine equivalent SPT N values from raw N30SB values.
Geotechnical characteristics of the red sands of Chibuto, Mozambique
Authors: Meintjes H.A.C.  , Jones G.A.
Published: February 2025

Red sands occur along the east coast of southern Africa from central Tanzania, through Mozambique to southern Natal and Eastern Province, South Africa. In a number of places the sands include heavy minerals which form economically viable mining deposits. One such deposit is located close to Chibuto, Mozambique and an extensive investigation was undertaken for the mineral processing plants. The geology of the area was known to be complex and the investigation which comprised primarily about 400 penetration tests (CPT, SPT and DPSH) confirmed that the red sands are extremely variable. A statistical method was adopted to define the variability so that a rational approach to foundation design could be used. The different penetration test results were correlated and confirmed that the conventional correlation factors were valid. Plate load tests, before and after, dynamic compaction proved the efficacy of the compaction but these tests when correlated with CPTs showed that moduli derived from the latter were conservative by a factor of two. Pile tests showed that the pile loads for driven cast in situ piles estimated from CPTs were also conservative by a factor of two. The overall conclusion is that the red sands are more complex than may be assumed and that although their foundation performance may be better than the general correlations with penetration testing indicate, the extreme variability should lead to considerable caution when assessing investigation results.
Injection of Contraction Joints at Pretarouca Dam
Authors: Vilar António Costa  , Cruz Duarte
Published: February 2025

Within the scope of the “Pretarouca Dam Construction” Project the injection of joints' compartments between the blocks that comprise the dam body was carried out, to ensure its water-tightness and to achieve a monolithic behavior of the entire structure. The works carried out comprised three different stages: washing and saturation of the joint compartments with water, filling up secondary circuits with bentonite (for preservation against deficient operation of non-return valves) and injection of the joints with cement grout, with special emphasis on the use of bentonite.
Application of soil-cement modification in weathered shale for road construction
Authors: Sukolrat J.  , Ongsuksun B.  , Klummeng A.  , Dechasakulsom M.
Published: February 2025

Thailand's Department of Highway is responsible for construction, services, and maintenance of most of the roads in Thailand. Every year, there is a large amount of new construction and repair all over the country where many of the nearby construction materials have been used up. In recent years, signs of construction materials shortages have emerged. Further, the high price of gasoline makes the transportation of materials from other areas uneconomical. In order to solve this problem, attention has therefore been drawn to acquiring local materials that are easily accessed and can be improved for road structure. Weathered shale is one of the most abundant materials that are found throughout the country. However its engineering properties are notorious and the untreated weathered shale is prohibited by the Department of Highway from any types of construction. The purpose of this research is to create a guideline of how to improve the engineering properties of weathered shale by using soil-cement application. The weathered shale samples were taken from various parts of Thailand and tested in the laboratory under control by Bureau of Road Research and Development. The optimum amount of the Portland cement is determined from the improvement of engineering properties, including: CBR, strength, stress-strain relationship, and durability.
Construction of Papadia secant pile plastic concrete cut-off wall
Authors: Anastasopoulos K.  , Economidis Ch.  , Bruce D.A.  , Rizopoulos G.
Published: February 2025

In order to secure the water-tightness of the foundation of the 67m high Papadia rockfill dam, a cut off wall up to 35.50m deep, formed by secant piles of plastic concrete was constructed in the Pleio-Pleistocene fluvio-glacial deposits at the river bed. A rigorous Quality Assurance Program was implemented during construction. A great number of tests, both in the field as well as in the laboratory were performed in order to validate the quality of the structure. Two years after filling the reservoir, monitoring data confirm the satisfactory performance of the seepage control measures