Ray tracing techniques for computer games and isosurface visualization

Ray tracing is a powerful image synthesis technique, that has been used for high-quality offline rendering since decades. In recent years, this technique has become more important for realtime applications, but still plays only a minor role in many areas. Some of the reasons are that ray tracing is compute intensive and has to rely on preprocessed data structures to achieve fast performance. This dissertation investigates methods to broaden the applicability of ray tracing and is divided into two parts. The first part explores the opportunities offered by ray tracing based game technology in the context of current and expected future performance levels. In this regard, novel methods are developed to efficiently support certain kinds of dynamic scenes, while avoiding the burden to fully recompute the required data structures. Furthermore, todays ray tracing performance levels are below what is needed for 3D games. Therefore, the multi-core CPU of the Playstation 3 is investigated, and an optimized ray tracing architecture presented to take steps towards the required performance. In part two, the focus shifts to isosurface raytracing. Isosurfaces are particularly important to understand the distribution of certain values in volumetric data. Since the structure of volumetric data sets is diverse, op- timized algorithms and data structures are developed for rectilinear as well as unstructured data sets which allow for realtime rendering of isosurfaces including advanced shading and visualization effects. This also includes tech- niques for out-of-core and time-varying data sets.Ray-tracing ist ein flexibles Bildgebungsverfahren, das schon seit Jahrzehnten für hoch qualitative, aber langsame Bilderzeugung genutzt wird. In den letzten Jahren wurde Ray-tracing auch für Echtzeitanwendungen immer interessanter, spielt aber in vielen Anwendungsbereichen noch immer eine untergeordnete Rolle. Einige der Gründe sind die Rechenintensität von Ray-tracing sowie die Abhängigkeit von vorberechneten Datenstrukturen um hohe Geschwindigkeiten zu erreichen. Diese Dissertation untersucht Methoden um die Anwendbarkeit von Ray-tracing in zwei verschiedenen Bereichen zu erhöhen. Im ersten Teil dieser Dissertation werden die Möglichkeiten, die Ray- tracing basierte Spieletechnologie bietet, im Kontext mit aktueller sowie zukünftig erwarteten Geschwindigkeiten untersucht. Darüber hinaus werden in diesem Zusammenhang Methoden entwickelt um bestimmte zeitveränderliche Szenen darstellen zu können ohne die dafür benötigen Datenstrukturen von Grund auf neu erstellen zu müssen. Da die Geschwindigkeit von Ray-tracing für Spiele bisher nicht ausreichend ist, wird die Mehrkern- CPU der Playstation 3 untersucht, und ein optimiertes Ray-tracing System beschrieben, das Ray-tracing näher an die benötigte Geschwindigkeit heranbringt. Der zweite Teil beschäftigt sich mit der Darstellung von Isoflächen mittels Ray-tracing. Isoflächen sind insbesonders wichtig um die Verteilung einzelner Werte in volumetrischen Datensätzen zu verstehen. Da diese Datensätze verschieden strukturiert sein können, werden für gitterförmige und unstrukturierte Datensätze optimierte Algorithmen und Datenstrukturen entwickelt, die die Echtzeitdarstellung von Isoflächen erlauben. Dies beinhaltet auch Erweiterungen für extrem große und zeitveränderliche Datensätze

Automatic decomposition of planned assembly sequences into skill primitives

Abstract-This paper presents a new method to decompose complex sequences of assembly operations into skill primitives. This can be realized by analyzing hyperarcs of the underlying AND/ORgraphs representing automatically generated assembly plans. Features like local depart spaces, symbolic spatial relations, and the necessary tools classify the type of assembly operation (peg in hole, placements, alignments, etc.). Skill primitives are robot movements or commands for grippers and tools. The unified modeling language (UML) is used to model the robot tasks and skill primitives. A robot control system uses the skill primitives as input to select the desired control scheme (position, force, or hybrid). In addition to this, we use an algorithm to identify assembly process states considering static friction under uniform gravity to execute skill primitives. This enables a robot to select and modify its motion strategies adequately according to the state of the assembly operation

ubiquinone oxidoreductase (complex I) in Escherichia coli

The proton-pumping NADH:ubiquinone oxidoreductase, respiratory complex I, couples the electron transfer from NADH to ubiquinone with the translocation of protons across the membrane. In Escherichia coli the complex is made up of 13 different subunits encoded by the so-called nuo-genes. Mutants, in which each of the nuo-genes was individually disrupted by the insertion of a resistance cartridge were unable to assemble a functional complex I. Each disruption resulted in the loss of complex I-mediated activity and the failure to extract a structurally intact complex. Thus, all nuo-genes are required either for the assembly or the stability of a functional E. coli complex I. The three subunits comprising the soluble NADH dehydrogenase fragment of the complex were detected in the cytoplasm of several nuo-mutants as one distinct band after BN-PAGE. It is discussed that the fully assembled NADH dehydrogenase fragment represents an assembly intermediate of the E. coli complex I. A partially assembled complex I bound to the membrane was detected in the nuoK and nuoL mutants, respectively. Overproduction of the ΔNuoL variant resulted in the accumulation of two populations of a partially assembled complex in the cytoplasmic membranes. Both populations are devoid of NuoL. One population is enzymatically active, while the other is not. The inactive population is missing cluster N2 and is tightly associated with the inducible lysine decarboxylase. This article is part of a Special Issue entitled: Biogenesis/Assembly of Respiratory Enzyme Complexes

Entwicklung eines Konzeptes zur Erzeugung von Öko-Ziegenlammfleisch aus melkenden Beständen (Vortrag)

In contrast to the increasing demand for dairy goat products in Germany, a market for goat kid meat as a related product is more or less non-existing. Thus, the objective of our study was to develop a concept for organic goat kid meat production for dairy goat farms. In collaboration with a wholesaler, organic dairy goat farmers and marketing research the experimental part of our study was to find out if cross-breeding of meat-goats could improve meat quality and performance of fattening goat kids together with other factors like concentrate ratio of the diet, housing system as well as raising strategy. First results indicate that a low input level of concentrates of 10 % of total dry matter intake per goat kid and year is not sufficient to meet the requested carcass weight of 12 kg at slaughter

Alternative glues for the production of ATLAS silicon strip modules for the Phase-II upgrade of the ATLAS Inner Detector

The Phase-II upgrade of the ATLAS detector for the High Luminosity Large Hadron Collider (HL-LHC) includes the replacement of the current Inner Detector with an all-silicon tracker consisting of pixel and strip detectors. The current Phase-II detector layout requires the construction of 20,000 strip detector modules consisting of sensor, circuit boards and readout chips, which are connected mechanically using adhesives. The adhesive between readout chips and circuit board is a silver epoxy glue as was used in the current ATLAS SemiConductor Tracker (SCT). This glue has several disadvantages, which motivated the search for an alternative. This paper presents a study concerning the use of six ultra-violet (UV) cure glues and a glue pad for use in the assembly of silicon strip detector modules for the ATLAS upgrade. Trials were carried out to determine the ease of use, the thermal conduction and shear strength, thermal cycling, radiation hardness, corrosion resistance and shear strength tests. These investigations led to the exclusion of three UV cure glues as well as the glue pad. Three UV cure glues were found to be possible better alternatives. Results from electrical tests of first prototype modules constructed using these glues are presented.Comment: 23 pages, to be published in Journal of Instrumentatio

Der Auslauf in der ökologischen Schweinemast: Verschmutzungsverteilung und Ammoniakemissionen

Ammonia emissions are an important problem in agricultural systems. Organic pig production raises a claim to offer high animal welfare. However, gaseous emissions can exhaust out of outdoor runs. Many measurement technics to determine the ammonia volatilization in animal facilities exist. In outdoor runs it is necessary to define the air volume flow. In addition, the contaminated surface of the pig-yard is heterogeneous. Therefore, it is interesting if the ammonia concentration correlate with the amount of manure. The outdoor run has been divided in a matrix. The ammonia concentrations are determined with a multi-gas monitor (INNOVA 1312) in combination with a dynamic chamber. The study showed a difference in ammonia volatilization between roofed and unroofed outdoor runs. Furthermore there is a high variability of the Ammonia concentrations in the different patches of the matrix

The nuts and bolts of multimodal anaesthesia in the 21st century: a primer for clinicians.

PURPOSE OF REVIEW This review article explores the application of multimodal anaesthesia in general anaesthesia, particularly in conjunction with locoregional anaesthesia, specifically focusing on the importance of EEG monitoring. We provide an evidence-based guide for implementing multimodal anaesthesia, encompassing drug combinations, dosages, and EEG monitoring techniques, to ensure reliable intraoperative anaesthesia while minimizing adverse effects and improving patient outcomes. RECENT FINDINGS Opioid-free and multimodal general anaesthesia have significantly reduced opioid addiction and chronic postoperative pain. However, the evidence supporting the effectiveness of these approaches is limited. This review attempts to integrate research from broader neuroscientific fields to generate new clinical hypotheses. It discusses the correlation between high-dose intraoperative opioids and increased postoperative opioid consumption and their impact on pain indices and readmission rates. Additionally, it explores the relationship between multimodal anaesthesia and pain processing models and investigates the potential effects of nonpharmacological interventions on preoperative anxiety and postoperative pain. SUMMARY The integration of EEG monitoring is crucial for guiding adequate multimodal anaesthesia and preventing excessive anaesthesia dosing. Furthermore, the review investigates the impact of combining regional and opioid-sparing general anaesthesia on perioperative EEG readings and anaesthetic depth. The findings have significant implications for clinical practice in optimizing multimodal anaesthesia techniques (Supplementary Digital Content 1: Video Abstract, http://links.lww.com/COAN/A96)