A User-Centric Adaptive Story Architecture – Borrowing from Acting Theories.

Interactive virtual environments are becoming increasingly popular for their utility in education, virtual training, and entertainment. These applications often rely on a scenario that is revealed to the user as he/she interacts with synthetic objects and characters that inhabit virtual worlds. Current interactive narrative architectures used in the interactive entertainment industry often use decision trees, which are hard to author and modify. Some interactive entertainment productions are starting to use more generative techniques, such as plan-based or goal-based narrative. In this paper, I present an interactive narrative architecture that extends current research in interactive narrative by integrating a user modeling and user behavior analysis technique, which I argue facilities a more engaging and fulfilling experience. I have implemented the architecture within an interactive story called Mirage. The architecture resulted from an iterative design and development process involving a team that included film and theatre professionals. During this design and development process, I have experimented and evaluated different narrative techniques, which resulted in the proposed architecture

Desktop 3-D Interactive Drama – Applying Design Principles from the Performance Arts.

Increasing emotional engagement in 3-D interactive environments is a hard, but important problem. It is important for its potential utility in increasing motivation, involvement, and engagement. These constructs are not only useful for entertainment applications, but also impact training and edutainment applications due to the impact of emotions on learning (Ulate, 2002; Wolfe, 2001). Many researchers have explored several techniques, including enhancing the story content to stimulate emotional engagement, developing new algorithms for dynamically creating stunning visual effects, and enhancing 3-D sound. Theatre and film have integrated many techniques that increase engagement, attention, and emotional involvement. In this paper, I describe a set of new design techniques integrated in an architecture that uses theatric and cinematic theories, specifically acting and screenwriting methods, to stimulate and improve emotional engagement in 3-D interactive narratives. In this paper, I discuss two research directions: (1) defining an interaction model for 3-D interactive narrative based on screenwriting theories, and (2) developing an actor-based agent architecture to simulate believable actions within an interactive narrative. The resulting architecture was implemented and tested within Mirage, an interactive story based on the Greek Tragedy Electra. Based on the critiques from several participants, I deduce that the resulting architecture presents significantly encouraging design techniques that can potentially increase emotional involvement and dramatic content of an interactive desktop 3D VR experience. The system and approach presented in this paper demonstrates an important new direction that adds to the set of techniques currently used and expand the design methodologies to include methods from disciplines, such as performance arts, theatre, and film

Applying Principles from Performance Arts for an Interactive Aesthetic Experience

Heightening tension and drama in 3-D interactive environments is a hard, but important problem. It is important for its potential utility in increasing motivation, involvement, engagement, and providing an overall pleasing aesthetic experience. These constructs are not only useful for entertainment applications, but can also impact training and edutainment applications due to the impact of emotions on learning. To stimulate emotional engagement, many researchers have explored several techniques, including enhancing the story content, developing new algorithms for dynamically creating stunning visual effects, and enhancing 3-D sound. In this paper, I describe a set of new design techniques based on a study of film and theatre theories, including acting and screenwriting. These design techniques are integrated within a multiagent interactive drama architecture. In this paper, I will discuss this architecture elaborating on the implementation of the theories studied and discussed from film and performance arts

Intelligent Lighting for Game Environments

Lighting design is an important topic of game development. There are many functions that lighting assumes in game environments, including directing attention, establishing good action visibility, evoking emotions, setting atmosphere, and providing depth. Current lighting design techniques rely on static manually designed lighting, where designers set up the positions, angles, and colors for each light in a level. Game environments are dynamic and unpredictable; physical and narrative scene content, including character locations, tension, and narrative goals, change unpredictably in real time due to user interaction. Thus, current static techniques often do not adequately adapt to serve desired aesthetic and communicative functions or perceptual effects. Recently, Doom 3 incorporated dynamic real-time lighting and demonstrated many advantages of using real-time dynamic lighting in games, including heightening the emotional engagement and enhancing the overall interactive experience. However, the technique is scripted and tightly coupled to game content. In this article, we present ELE (Expressive Lighting Engine), an intelligent lighting system that automatically sets and adjusts scene lighting in real time to achieve aesthetic and communicative functions, including evoking emotions, directing visual focus, and providing visibility and depth. ELE operates as a separate system that interacts with game/graphics engines through a standard interface. In this article, we will discuss ELE and its interface with Unreal Tournament 2003. We will also present results showing ELE in action. These results show: the utility of real-time adaptive lighting in providing visual focus, setting atmosphere, evoking emotions, and establishing visibility during interaction in interactive environments; and acceleration in the development process due to the introduction of an automatic system for lighting that can be overridden by designers at a high level, thus eliminating the time-consuming process of setting individual light parameters for each level and scene

An Interactive Narrative Architecture Based on Filmmaking Theory

Designing and developing an interactive narrative experience includes development of story content as well as a visual composition plan for visually realizing the story content. Theatre directors, filmmakers, and animators have emphasized the importance of visual design. Choices of character placements, lighting configuration, and camera movements, have been documented by designers to have direct impact on communicating the narrative, evoking emotions and moods, and engaging viewers. Many research projects focused on adapting the narrative content to the interaction, yet little attention was given to adapting the visual presentation. In this paper, I present a new approach to interactive narrative – an approach based on filmmaking theory. I propose an interactive narrative architecture, that in addition to dynamically selecting narrative events that suit the continuously changing situation, it automatically, and in real-time, reconfigures the visual design integrating camera movements, lighting modulation, and character movements. The architecture utilizes rules extracted from filmmaking, cinematography, and visual arts theories. I argue that such adaptation will lead to increased engagement and enriched interactive narrative experience

Investigation of Bio-hydrogen and Bio-methane Production From Thin Stillage

An evaluation of single-stage and two-stage anaerobic digestion processes for biomethane and biohydrogen production using thin stillage was performed to assess the viability of biohydrogen production from thin stillage and the impact of separating the acidogenic and methanogenic stages on anaerobic digestion with hydrogen production in the first stage. A comparative evaluation of anaerobic digester sludge (ADS) and acclimatized anaerobic digester sludge (AADS) for biohydrogen production was performed at various S°/X° ratios. The optimum range of S°/X° ratio for hydrogen production was found to be 1 to 2 gCOD/gVSS using conventional ADS and 3 to 6 gCOD/gVSS using AADS. Maximum methane yields of 0.33 L CH4/gCODadded and 0.26 L CH4/gCODadded were achieved in the two-stage and the single-stage processes, respectively. An artificial neural network model was developed to estimate the hydrogen production profile with time in batch studies and successfully predicted it with a correlation coefficient of 0.965

Israeli nuclear deterrence: the failure of a concept: how did the change in Israel\u27s strategic context affect the usefulness of the Israeli nuclear deterrent?

This study will aim at examining how the changes in Israelâ s security environment affected the strategic usefulness of its nuclear deterrent. The Israeli nuclear deterrent was developed during the 1950s and the 1960s when Israelâ s strategic setting was, mainly, dominated by state-centered security threats. Consequently, Israel, at the time, was mainly concerned with the possible symmetrical military confrontations with its Arab neighbors; something that would have created strategic value for the Israeli nuclear deterrent. Yet, a closer examination of the evolution of the Israeli security environment since 1982 will reveal that Non-State Actors (NSAs) and asymmetrical forms of warfare, slowly but surely, have dominated the Israeli security setting. The year 1982 is chosen because it is the date of the last major military confrontation between Israel and another state (Syria in that case) in a symmetrical form of warfare. Since then, Israelâ s major security threats originated from NSAs either operating from neighboring states (as in the case of Hezbollah in Lebanon) and/or Palestinian groups operating in Israel or from the occupied Arab territories in the West Bank and the Gaza Strip. The most obvious example of this new type of threats is the highly successful campaign launched by Hezbollah, throughout the 1980s and 1990s, against the Israeli occupation of Southern Lebanon, which eventually led to an Israeli withdrawal in 2000. In this campaign Hezbollah depended on asymmetrical forms of warfare that left the Israeli Defense Forces (IDF) entangled in a long and destructive war of attrition. In addition to Hezbollah, both the first and the second Intifadas proved to be a great security threat to Israel, as the Palestinians, generally and more so in the second Intifada, devised and restored to asymmetrical means of warfare that proved hard to break using conventional military means. This rise of threats stemming mainly of NSAs and asymmetrical means of warfare was coupled with the simultaneous and relative decline of state-centered security threats; which are threats mainly originating from states mounting regular and symmetrical wars. In fact, this relative decline of state-centered security threats initiated by a complex set of, often interrelated, political and strategic factors. This study will aim, first, at providing a comprehensive overview of how and which context did Israel develop its nuclear deterrent and how was it related to the Israeli self-perception and strategy of deterrence. Second, the study will tackle the changes that took place in Israelâ s strategic setting over the past three decades; discussing, in the process, the various political and strategic factors that led to the decline of the state-centered security threats and the simultaneous rise of NSAs as Israelâ s main security threat. Finally, the effect of this change in Israelâ s threat map on the usefulness of Israeli nuclear deterrent will be examined

Investigation of Bio-hydrogen Production Optimization from Synthetic and Real Wastes using Pure and Mixed Cultures

Dark fermentative H2 production is an important route to renewable energy as it is based on a known technology and can utilize a wide range of available waste streams as substrate. However, more research is required to overcome the technical barriers to practical application. The aim of this study is to investigate different scenarios towards the optimization of fermentative H2 production from synthetic and real wastes using pure and mixed cultures. Lignocellulosic biomass, i.e. pretreated corn cobs and poplar wood hydrolysate were evaluated for H2 production using mixed anaerobic cultures and yields of 141 and 169 mL H2/gCODadded were determined, respectively. Also, substrate utilization kinetic parameters for selected mesophilic and thermophilic H2-producing pure cultures utilizing hexose and pentose sugars were determined. Furthermore, the effect of co-fermentation and co-cultures on H2 production was studied. This work proved that headspace CO2 sequestration in a continuous-flow system producing H2 from glucose increased H2 yield from 2.4 to 3.0 mol/mol glucose, i.e. approximately 90% of the theoretical yield. An extensive comparative study of mesophilic and thermophilic anaerobic digester sludges confirmed the superiority of thermophilic cultures which produced 23.8 L H2/L poplar wood hydrolysate. The Monod kinetic parameters of mono- and co-culture of Clostridium beijerinckii and Clostridium saccharoperbutylacetonicum on glucose, starch, and cellulose were derived