Plastics, Degradability, and the Environment

Harmful environmental effects of plastics have long been condemned by activists, and some of these problems are well documented. However, in seeking to substitute other materials or make changes in the properties of the plastics themselves, it is important that the policies implemented do not worsen existing or create new environmental problems. This seminar will discuss some of the general concerns associated with this issue, such as the environmental impacts of using other materials instead of plastics, and then focus on degradable plastics. What is degradability, when might it be valuable, and will these products in fact degrade? Results of a study on biodegradable plastics under anaerobic conditions (such as in most sludge digestion and landfills) will be presented

Strategic flexibility and Business valuation

Business valuation is essential at every stage of the firm life cycle, from establishing investment value for early and later stage growth venture capital funding to pricing of private equity transactions or initial public offerings, and for assessment of stock prices in public markets. Firms typically evolve in markets under competition and demand dynamics where uncertainty around their future opportunities has implications for investments, survival and available strategic choices. Value creation under such circumstances is dependent on strategic flexibility in response to changes in the business environment that introduce path-dependency and significant non-linear effects into the earnings processes. In spite of its importance, studies uncover that fundamental business valuation approaches commonly applied within venture capital, private equity and public equity are unable to effectively explain non-linear effects, and also that we know comparably little about how firms’ strategic behaviour and decisions relate to firm performance and value across firm development stages.Hence, the purpose of this thesis is to contribute to knowledge by investigating how increased understanding of strategic flexibility at all firm development stages can lead to improved fundamental business valuation. Given the fragmented state of the research, this study opens with a critical review of the literatures, followed by two research papers that each address identified limitations using large samples of listed firms to allow for estimation of implied growth options useful to the analysis. The first paper addresses the open question whether business model dimensions can provide an effective approach to peer selection. The findings, despite an early contribution, suggest that strategic dimensions provide incremental information over common industry-anchored approaches with applications suitable for firms with limited financial history. In the second paper, recent evidence in the real options research that links effects of fundamental skewness to realised firm-level flexibility is extended to address the lack of a comparable proxy for strategic flexibility in the strategic management literature by proposing a novel proxy (strategic intensity). The proxy is applied to analyse and answer open questions about firm-level flexibility, growth, survival and value creation across stages of firm development. Findings confirm a general positive relationship between realised strategic flexibility and performance, and uncover that higher levels of strategic flexibility exhibit long-term persistence, and can predict future levels of profitability and market value.The thesis makes two major methodical contributions in line with the purpose. The addition of strategic intensity adds a lens to increase our understanding of how firms are able to realise strategic flexibility with applications in research and valuation, and peer selection on strategic choice via business model dimensions provides a succinct method suitable for firm valuation

Optical/IR from ground

Optical/infrared (O/IR) astronomy in the 1990's is reviewed. The following subject areas are included: research environment; science opportunities; technical development of the 1980's and opportunities for the 1990's; and ground-based O/IR astronomy outside the U.S. Recommendations are presented for: (1) large scale programs (Priority 1: a coordinated program for large O/IR telescopes); (2) medium scale programs (Priority 1: a coordinated program for high angular resolution; Priority 2: a new generation of 4-m class telescopes); (3) small scale programs (Priority 1: near-IR and optical all-sky surveys; Priority 2: a National Astrometric Facility); and (4) infrastructure issues (develop, purchase, and distribute optical CCDs and infrared arrays; a program to support large optics technology; a new generation of large filled aperture telescopes; a program to archive and disseminate astronomical databases; and a program for training new instrumentalists

A new aerosol wet removal scheme for the Lagrangian particle model FLEXPART v10

A new, more physically based wet removal scheme for aerosols has been implemented in the Lagrangian particle dispersion model FLEXPART. It uses three-dimensional cloud water fields from the European Centre for MediumRange Weather Forecasts (ECMWF) to determine cloud extent and distinguishes between in-cloud and below-cloud scavenging. The new in-cloud nucleation scavenging depends on cloud water phase (liquid, ice or mixed-phase), based on the aerosol's prescribed efficiency to serve as ice crystal nuclei and liquid water nuclei, respectively. The impaction scavenging scheme now parameterizes below-cloud removal as a function of aerosol particle size and precipitation type (snow or rain) and intensity. Sensitivity tests with the new scavenging scheme and comparisons with observational data were conducted for three distinct types of primary aerosols, which pose different challenges for modeling wet scavenging due to their differences in solubility, volatility and size distribution: (1) Cs-137 released during the Fukushima nuclear accident attached mainly to highly soluble sulphate aerosol particles, (2) black carbon (BC) aerosol particles, and (3) mineral dust. Calculated e-folding lifetimes of accumulation mode aerosols for these three aerosol types were 11.7, 16.0, and 31.6 days respectively, when well mixed in the atmosphere. These are longer lifetimes than those obtained by the previous removal schem, and, for mineral dust in particular, primarily result from very slow in-cloud removal, which globally is the primary removal mechanism for these accumulation mode particles. Calculated e-folding lifetimes in FLEXPART also have a strong size dependence, with the longest lifetimes found for the accumulation-mode aerosols. For example, for dust particles emitted at the surface the lifetimes were 13.8 days for particles with 1 aem diameter and a few hours for 10 aem particles. A strong size dependence in below-cloud scavenging, combined with increased dry removal, is the primary reason for the shorter lifetimes of the larger particles. The most frequent removal is in-cloud scavenging (85% of all scavenging events) but it occurs primarily in the free troposphere, while below-cloud removal is more frequent below 1000m (52% of all events) and can be important for the initial fate of species emitted at the surface, such as those examined here. For assumed realistic in-cloud removal efficiencies, both BC and sulphate have a slight overestimation of observed atmospheric concentrations (a factor of 1.6 and 1.2 respectively). However, this overestimation is largest close to the sources and thus appears more related to overestimated emissions rather than underestimated removal. The new aerosol wet removal scheme of FLEXPART incorporates more realistic information about clouds and aerosol properties and it compares better with both observed lifetimes and concentration than the old scheme.Peer reviewe

Making the great transformation, November 13, 14, and 15, 2003

This repository item contains a single issue of the Pardee Conference Series, a publication series that began publishing in 2006 by the Boston University Frederick S. Pardee Center for the Study of the Longer-Range Future. This Conference took place during November 13, 14, and 15, 2003. Co-organized by Cutler Cleveland and Adil Najam.The conference discussants and participants analyze why transitions happen, and why they matter. Transitions are those wide-ranging changes in human organization and well being that can be convincingly attributed to a concerted set of choices that make the world that was significantly and recognizably different from the world that becomes. Transition scholars argue that that history does not just stumble along a pre-determined path, but that human ingenuity and entrepreneurship have the ability to fundamentally alter its direction. However, our ability to ‘will’ such transitions remains in doubt. These doubts cannot be removed until we have a better understanding of how transitions work

Visual Prosody: Facial Movements Accompanying Speech

As we articulate speech, we usually move the head and exhibit various facial expressions. This visual aspect of speech aids understanding and helps communicating additional information, such as the speaker's mood. We analyze quantitatively head and facial movements that accompany speech and investigate how they relate to the text's prosodic structure. We recorded several hours of speech and measured the locations of the speakers' main facial features as well as their head poses. The text was evaluated with a prosody prediction tool, identifying phrase boundaries and pitch accents. Characteristic for most speakers are simple motion patterns that are repeatedly applied in synchrony with the main prosodic events. Direction and strength of head movements vary widely from one speaker to another, yet their timing is typically well synchronized with the spoken text. Understanding quantitatively the correlations between head movements and spoken text is important for synthesizing photo-realistic talking heads. Talking heads appear much more engaging when they exhibit realistic motion pattern