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The research project has aimed to support decision making regarding possible transition towards an up-to-date, sustainable geo-ict architecture based on an analysis of technical factors that influence performance of geoprocessing tools at the spatial team of Statistics Netherlands and experiences at comparable organizations. The current geoprocessing environment is ArcInfo Workstation and ArcGIS Desktop 10.1, although most production processes are conducted in ArcInfo Workstation and its scripting language AML. Support of ArcInfo Workstation will not be continued after 2015. Therefore, migration of these processes to ArcGIS Desktop 10.1 or higher version of this product suite has to be considered. Consequently, the following research question has been formulated: Which alternatives to the current geo-ict infrastructure can be proposed for Statistics Netherlands that meet performance requirements of its geoprocessing activities and are suitable for implementation within the organizational constraints of Statistics Netherlands? Based on studying the workload, resources and performance bottlenecks at Statistics Netherlands, a benchmark has been developed evaluating four geoprocessing tools (UNION, INTERSECT, DISSOLVE and NEAR) to be tested on scalability (using synthetic data), impact of optimization factors available in ArcGIS Desktop 10.1 and impact of big data hardware and new software releases ArcGIS 10.2 and ArcGIS Pro (using real data). A number of administrative processing tools (SUMMARY STATISTICS, FREQUENCY, CALCULATE and JOIN FIELD) has been additionally included for tests with the big data hardware and the new software releases. The results of the benchmark have been combined with migration experiences of ArcInfo to ArcGIS Desktop or ArcSDE from other organizations and held against possible internal and external restrictions and trends. These organizations are Statistics Portugal, Statistics Italy, United States Geological Survey and PBL (Netherlands Environ

Heat stress can cause sterility in sorghum and the anticipated increased frequency of high temperature events implies increasing risk to sorghum productivity in Australia. Here we summarise our research on specific varietal attributes associated with heat stress tolerance in sorghum and evaluate how they might affect yield outcomes in production environments by a crop simulation analysis. We have recently conducted a range of controlled environment and field experiments to study the physiology and genetics of high temperature effects on growth and development of sorghum. Sorghum seed set was reduced by high temperature effects (>36-38oC) on pollen germination around flowering, but genotypes differed in their tolerance to high temperature stress. Effects were quantified in a manner that enabled their incorporation into the APSIM sorghum crop model. Simulation analysis indicated that risk of high temperature damage and yield loss depended on sowing date, and variety. While climate trends will exacerbate high temperature effects, avoidance by crop management and genetic tolerance seems possible.

The popularity, availability and sizes of point cloud data sets are increasing, thus raising interesting data management and processing challenges. Various software solutions are available for the management of point cloud data. A benchmark for point cloud data management systems was defined and it was executed for several solutions. In this paper we focus on the solutions based on the column-store MonetDB, the generic out-of-the-box approach is compared with two alternative approaches that exploit the spatial coherence of the data to improve the data access and to minimize the storage requirements

Item does not contain fulltext, This contribution discusses the feasibility of extracting the major features of repolarization: its spatio-temporal behaviour, and how much of its global or local behaviour might be deduced from signals that can be observed experimentally. The analysis presented is based on source-volume-conductor configurations ranging from the classic cable theory, with sources derived from reaction diffusion computations, to a realistic thorax model comprising a whole heart model with electric sources represented by the equivalent electric double layer. The analysis focuses on the fact that the local activation recovery interval (ARI) at regions activated by expanding wave fronts is significantly longer than those activated by contracting ones. The consequences of this effect on observed magnitude and wave form of recorded signals are illustrated.

Item does not contain fulltext, The solution of the mixed boundary value problem of potential theory involves the computation of the potential field generated by monolayer and double layer source distributions on surfaces at which boundary conditions are known. Closed-form analytical expressions have been described in the literature for the potential field generated by double layers having a linearly distributed strength over triangular source elements. This contribution presents the corresponding expression for the linearly distributed monolayer strength. The solution is shown to be valid for all observation points in space, including those on the interior, edges and vertices of the source triangle.

Item does not contain fulltext, This invited paper presents a personal view on the current status of the solution to the inverse problem of bioelectricity. Its focus lies on applications in the field of electrocardiography. The topic discussed is also relevant in other medical domains, such as electroencephalography, electroneurography and electromyography. In such domains the methodology involved rests on the same basic principles of physics and electrophysiology as well as on the applied techniques of signal analysis and numerical analysis.

The relational data model is now more than 40 years old. It's good for very different scenarios and can handle certain types of data very well. But it isn't perfect. An increasing number of non-relational systems are being worked on, collectively called the 'NoSQL movement'. NoSQL is an umbrella term for a loosely defined class of non-relational datastores and best described as 'Not only SQL'. Examples are Google's BigTable and Amazon's Dynamo. These systems may provide advantages over relational databases, but generally lack the relational robustness for those advantages. In an attempt to modestly contribute to the current research in the field of geographical information systems, this research reports on a comparison of one such NoSQL datastore called Neo4j with the traditional relational database PostgreSQL when storing and querying spatial vector data. The goal of this study was to determine whether a traditional relational database system like PostGIS, or a NoSQL system, such as Neo4j-Spatial, would be more effective as the underlying technology for operating OpenStreetMap data. Neo4j is an embeddable graph database. Embeddable because it can be added to a Java-based application and used just like any other library, and graph database because the data model it uses to express its data is a graph, storing nodes and relationships that connect them, supporting user defined properties on both constructs. Multiple aspects are of interest when comparing spatial database systems. The evaluation methodology designed to compare the two, involves both objective measurements and subjective measurements based on documentation and experience. The objective tests include processing speed based on a predefined set of queries, disk space requirements, and scalability. Subjective tests include maturity/level of support, stability and ease of use. Meanwhile, the assessment framework applied for the objective tests could be used as a test suite for evaluating the performance and

Item does not contain fulltext, This contribution demonstrates some applications of the most recent release of ECGSIM, an interactive simulation program that enables the user to study the relationship between the electric current sources of the heart and the resulting electrocardiographic signals on the body surface as well as those on the surface of the heart. It aims to serve as an educational tool as well as a research tool. The examples are drawn from the topics discussed by the participants of the Magnetic Anatomic and eLectrical Technology meeting in Maastricht, the Netherlands (February 2011), reports of which are to be found in the current issue of the Journal of Electrocardiology. These examples include simulation of the atrial electrocardiogram, improved accessibility of endocardial source locations, and an explanation of ST elevations accompanying true TQ depressions.

Item does not contain fulltext, Determining electrical activation of the heart in a noninvasive way is one of the challenges in cardiac electrophysiology. The ECG provides some, but limited information about the electrical status of the heart. This article describes a method to determine both endocardial and epicardial activation of the heart of an individual patient from 64 electrograms recorded from the body surface. Information obtained in this way might be helpful for the treatment of arrhythmias, to assess the effect of drugs on conduction in the heart and to assess electrical stability of the heart.

RU Radboud Universiteit Nijmegen, 05 februari 2010, Promotor : Oosterom, A. van Co-promotor : Oostendorp, T.F., Contains fulltext : 74933.pdf (publisher's version ) (Open Access), This thesis describes the application of the shortest path algorithm in the simulation of cardiac activation. This method is both used in the forward simulation of an electrocardiogram (ECG) as well as in the non-invasive imaging of cardiac activation and recovery. Due to the immense number of cardiac cells a source model is required to simulate the electrical cardiac generator. The source model used in this thesis is the equivalent double layer source model. One of the major advantages of this model is the close relation with electrophysiological characteristics of the cardiac cells. This enables the introduction of electrophysiological knowledge in the require initial estimate on behalf of the non-invasive imaging method. Knowledge on the propagation of activation within the myocardial tissue was introduced to generate realistic activation patterns, both for the atria and the ventricles. The inverse procedure described in this thesis proves to be robust, both in respect to the number of leads used and to the waveform parameterization used in the source model. The robustness is mainly attributed to the high quality of the initial activation estimate based on the dedicated implementation of the shortest path algorithm, the fastest route algorithm. This results in an initial estimate that is close to the actual activation and recovery times, which minimize the risk that the subsequently applied inverse procedure ends up in an unrealistic local minimum in the parameter space. The clinical application of this inverse procedure is now coming within reach. Selecting the optimal lead system might enable the inverse procedure to be executed by using a limited number of leads (15-30). For specific cases and research applications, like shown for the Brugada patient, the proposed non-invasive imaging method seems to have reached maturity.

The goal of this research is to develop a 3D topological structure with validation functionality and a conversion function. In order to reach this goal, the main requirements for a 3D topological structure are set, as well as ten validation rules. The designed 3D topological structure represents a full space partition of volumes. A prototype of this structure has been implemented in Oracle Spatial (11g). The validation rules have been translated into validation tests, which have been implemented on the structure. Finally, for each primitive (node, edge, face and volume) a geometry operation has been implemented on the structure.

Landadministratie en de (G)II zijn een middel om de uitdagingen in onze steeds complexer wordende maatschappij het hoofd te bieden. In een netwerkmaatschappij is het dan ook van doorslaggevende betekenis dat alle partijen begrip voor elkaar kunnen opbrengen, ook al hanteren ze een andere terminologie. Een reeks van begrippen waar in brede zin consensus over is bereikt is noodzakelijk en wordt aangereikt door het LADM (Land Administration Domain Model)

Dit artikel gaat in op toepassingen van kadastrale informatie in het raamwerk van een geo-informatie infrastructuur en wel specifiek op wereldschaal. Kadasters vormen de basis om rechten op onroerende zaken inzichtelijk te maken, evenals de beperkingen die er op rusten en de verantwoordelijkheden die dit grondbezit met zich meebrengt. Daarbij bestaat een duidelijke relatie met het grondbeleid, de locatie, en de mensen in hun rol als rechthebbende

Contains fulltext : 81292.pdf (publisher's version ) (Closed access), The sequences of activation and recovery of the heart have physiological and clinical relevance. We report on progress made over the last years in the method that images these timings based on an equivalent double layer on the myocardial surface serving as the equivalent source of cardiac activity, with local transmembrane potentials (TMP) acting as their strength. The TMP wave forms were described analytically by timing parameters, found by minimizing the difference between observed body surface potentials and those based on the source description. The parameter estimation procedure involved is non-linear, and consequently requires the specification of initial estimates of its solution. Those of the timing of depolarization were based on the fastest route algorithm, taking into account properties of anisotropic propagation inside the myocardium. Those of recovery were based on electrotonic effects. Body surface potentials and individual geometry were recorded on: a healthy subject, a WPW patient and a Brugada patient during an Ajmaline provocation test. In all three cases, the inversely estimated timing agreed entirely with available physiological knowledge. The improvements to the inverse procedure made are attributed to our use of initial estimates based on the general electrophysiology of propagation. The quality of the results and the required computation time permit the application of this inverse procedure in a clinical setting.

Contains fulltext : 80169.pdf (publisher's version ) (Closed access), A method is described to determine the effect on the ECG of a reduced propagation velocity within an ischemic zone. The method was designed to change the activation sequence throughout the ventricles interactively, i.e. with a response time in the order of a second. The timing of ventricular ischemic activation was computed by using the fastest route algorithm, based on locally reduced values of the propagation velocities derived from a standard, normal activation sequence. The effect of these local reductions of the velocities on the total activation sequence, as well as the changes in the electrocardiogram that these produce, are presented.

De rol van landadministratie is dermate belangrijk en vaak gerelateerd aan andere (geo-)informatie thema's, zoals gebouwen, (water)wegen en adressen, kabels en leidingen, landgebruik, personen, bedrijven, rechten, enz. dat we die rol zelfs als hoeksteen zien binnen de (geo-)informatie infrastructuur. Dit artikel gaat over de internationale ontwikkeling om het kennisgebied (domein) van kadaster en landadministratie te normeren.

In order to assess and possibly improve our practice of hand fracture treatment, studies were performed that led to this thesis, introduced in chapter 1. An evidence-based protocol and manual of operative treatment of fractures of phalanges was compiled, chapter 2. The results of operative treatment of phalangeal fractures at the department of Plastic, Reconstructive, and Hand Surgery of the Erasmus University Medical Center, Rotterdam, the Netherlands were assessed and risk factors for nonunion and malunion identified, chapter 3. The digital functional loss in severely injured hands was quantified (chapter 4). Associated soft tissue injury, level of injury, and arthrodesis were risk factors for diminished function. A quantification of digital functional loss for combinations of these risk factors was made. In chapter 5, correlation between impairment and disability was assessed following treatment for severe hand injuries. No statistically significant correlation existed between AMA impairment ratings for the hand and DASH (disability) module scores. A prospective study audit was performed on quality of treatment of phalangeal and metacarpal fractures, chapter 6. Eighty-three percent of diagnoses were correct and 89% of treatment plans were according to protocol, 80% healed properly, and osteosynthesis was deemed adequate in 81% of cases. In chapter 7, financial and logistic impact of phalangeal and metacarpal fractures was prospectively assessed. Hospital costs, hospital visits, days in the hospital, number of operations, and period off work were recorded. Variables that influenced outcome data were statistically tested. In chapter 8 results of the aforementioned studies are discussed, and recommendations for improvement of operative treatment of phalangeal and metacarpal fractures are provided.

Introduction. December the 26th 2004 a massive undersea earthquake northwest of Sumatra, Indonesia, with a Richter-scale magnitude of 9.3, caused a giant shockwave or tsunami that devastated the shorelines of Indonesia, Sri Lanka, India, Thailand, and many other countries (van Griensven et al., 2006). Thousands of people from all over the world were reported missing or dead. Besides the enormous death toll, other far-reaching consequences followed. It is important to raise the awareness of psychological consequences resulting from major trauma. With insight in these consequences there can be anticipated upon obstacles in psychological aid. Theoretical background. Psychological consequences of natural disasters have been studied extensively. The most notably measured psychological problem was posttraumatic stress disorder (PTSD). Exposure, seen as one of the most influencing factors in developing PTSD is investigated. The central question raised in the research is: Do individuals who are exposed more severely to the tsunami have more PTSD-symptoms and how strong is the possible relationship between exposure and symptoms after three years? Method. Starting the study first qualitative research was done. With use of TISEI-internetquestionnaires (www.tisei.org) the focus of the study was on PTSD-symptoms among Dutch survivors who were present in one of the affected regions at the time of the tsunami or were indirectly influenced by it. Participants at T1 were 28 Dutch males (38,4%) and 45 Dutch females (61,6%). At T2 (three years after the tsunami) participants were 15 Dutch males (40,1%) and 22 Dutch females (59,6%). For measuring exposure, questions that revealed a form of exposure to the tsunami on the TISEI-website were used. A factoranalysis was conducted which revealed at T1 two factors, which were not replicated at T2. Davidson Trauma Scale (DTS) was used to assess PTSD symptoms cross-sectionally. Regressionanalysis were used to assess the relationship between exp

Om automatische generalistie van topografische data te ondersteuen is een studie gedaan naar het ontwerp van een multi-schaal informatiemodel voor topografie. In het onderzoek zijn verschillende modelleeralternatieven uitgewerkt en is een prototype vervaardigd en getest Het onderzoek geeft inzicht in mogelijke tools, talen en technieken.

Voor een onderzoek naar integratie van grootschalige en middenschalige topografie in één structuur is gebruik gemaakt van gegevens uit Almere en Rotterdam. Resultaat is een nauwkeurige geometrie van de grootschalige objecten, verrijkt met de generalisatiekennis van middenschalige gegevens

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Contains fulltext : 49305.pdf (publisher's version ) (Closed access)

Item does not contain fulltext, OBJECTIVE: We aimed to study the involvement of atrial repolarization in body surface potentials. METHODS: Electrocardiograms of healthy subjects were recorded using a 64-lead system. The data analysis focused on the PQ intervals while devoting special attention to the low-amplitude signals during the PQ segment: the segment from the end of the P wave until onset QRS. The data were analyzed by inspecting body surface potential maps and the XYZ signals of the vectorcardiogram. RESULTS: Standard P-wave features exhibited normal values. The local potential extremes were found at positions not sampled by the standard leads. The PQ segment was found to be not isoelectric, the time course of the potential distribution being very similar to that during the P wave but for a reversed polarity and about 3-fold lower magnitudes. CONCLUSION: The results demonstrate a significant involvement of atrial repolarization during the PQ interval and essentially discordant "atrial T waves," suggesting a small dispersion of atrial action potential durations.

Item does not contain fulltext, PURPOSE: Halofuginone (tempostatin) is a synthetic derivative of a quinazolinone alkaloid showing anti-angiogenic, anti-metastatic and anti-proliferative effects in preclinical studies. The objectives of this phase I study were to assess the dose-limiting toxicities (DLTs), to determine the maximum tolerated dose (MTD) and to study the pharmacokinetics (PKs) of halofuginone when administered once or twice daily orally to patients with advanced solid tumours. METHODS: Patients were treated with escalating doses of halofuginone at doses ranging from 0.5 to 3.5 mg/day. For pharmacokinetic analysis plasma sampling was performed during the first and second course and assayed using a validated high-performance liquid chromatographic assay with mass spectrometric detection. RESULTS: Twenty-four patients received a total of 106 courses. The 'acute' MTD was reached at 3.5 mg/day, with nausea, vomiting, and fatigue as DLT. The recommended dose for chronic administration was defined as 0.5mg/day with the requirement of 5HT3 antagonists to control nausea and vomiting considered as DLT. Several patients experienced bleeding complications on treatment with halofuginone in which a causal relationship could not be excluded. The PKs of halofuginone were linear over the dose range studied with a large interpatient variability. CONCLUSIONS: In this study the DLT of halofuginone was nausea, vomiting, and fatigue. The recommended dose for phase II studies of halofuginone is 0.5mg administered orally, once daily.

Topografische producten moeten worden uitgebreid naar de derde dimensie. Een onderzoek naar de modellering hiervan vindt plaats binnen het Bsik RGI project '3D-topografie'. In dit artikel wordt een nieuw datamodel gepresenteerd, gebaseerd op de wiskundige theorie van de Poincaré-algebra (TEN staat voor Tetraheder Netwerk)