330 research outputs found
Parameterized model order reduction of delayed systems using an interpolation approach with amplitude and frequency scaling coefficients
When the geometric dimensions become electrically large or signal waveform rise times decrease, time delays must be included in the modeling. We present an innovative PMOR technique for neutral delayed differential systems, which is based on an efficient and reliable combination of univariate model order reduction methods, amplitude and frequency scaling coefficients and positive interpolation schemes. It is able to provide parameterized reduced order models passive by construction over the design space of interest. Pertinent numerical examples validate the proposed PMOR approach
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Unraveling the "passion orchestra" in academia
This paper disentangles how organization members' âpassion orchestraâ is related to their entrepreneurial intentions in the particularly relevant context of academia. Drawing on passion literature and identity theory, we propose and test a model linking two central parts of researchers' âpassion orchestraâ, namely entrepreneurial and obsessive scientific passion, directly and indirectly, to spin-off and start-up intentions. While spin-off intentions refer to intentions to found a firm based upon research results, start-up intentions denote intentions to start any type of company. Using a sample of 2308 researchers from 24 European universities, our findings reveal that higher levels of entrepreneurial passion are associated with both stronger spin-off and start-up intentions. Further, obsessive scientific passion is positively associated with researchers' intentions to create a spin-off, and negatively with their propensity to establish a start-up. Entrepreneurial self-efficacy and affective organizational commitment mediate these effects. Finally, the two types of passion show characteristic interactions. Obsessive scientific passion moderates the entrepreneurial passionâintentions relationship such that it strengthens spin-off intentions. Our results highlight that recasting the individual driven by a singular passion to one with a âpassion orchestraâ provides a more holistic understanding of the new venture creation process. Implications for research and practice are discussed
Signal Strength, Media Attention, and Resource Mobilization: Evidence from New Private Equity Firms
This is the author accepted manuscript. The final version is available from the Academy of Management via the DOI in this recordPast research has shown that new firms can facilitate resource mobilization by signaling their unobservable quality to prospective resource providers. However, we know less about situations in which firms convey multiple signals of different strengthsâi.e., signals that are more or less correlated with unobservable firm quality. Building on a sociocognitive perspective, we propose that prospective resource providers respond differently to signals of different strengths and that the effectiveness of signals, especially weak signals, will be contingent on the media attention new firms receive. Empirically, we conduct a longitudinal analysis examining the ability of new private equity (PE) firms to raise a follow-on fund. Consistent with our theory, we find that unrealized performance, a relatively weak signal, positively influences fundraising. But we fail to find statistical evidence that its effect is weaker than that of realized performance, a relatively strong signal. Further, media attention strengthens the relationship between unrealized performance and fundraising, but media attention exerts less impact on the relationship between realized performance and fundraising. Taken together, our findings deepen our understanding of how new firms can mobilize resources with signals of different strengths and of how the mediaâas a key information intermediaryâdifferently impacts their effectiveness.Richard M. Schulze Family Foundatio
Toward a Harmonization for Using in situ Nutrient Sensors in the Marine Environment
Improvedcomparabilityofnutrientconcentrationsinseawaterisrequiredtoenhancethe quality and utility of measurements reported to global databases. SigniïŹcant progress has been made over recent decades in improving the analysis and data quality for traditional laboratory measurements of nutrients. Similar efforts are required to establish high-quality data outputs from in situ nutrient sensors, which are rapidly becoming integral components of ocean observing systems. This paper suggests using the good practices routine established for laboratory reference methods to propose a harmonized setofdeploymentprotocolsandofqualitycontrolproceduresfornutrientmeasurements obtained from in situ sensors. These procedures are intended to establish a framework to standardize the technical and analytical controls carried out on the three main types of in situ nutrient sensors currently available (wet chemical analyzers, ultraviolet optical sensors, electrochemical sensors) for their deployments on all kinds of platform. The routine reference controls that can be applied to the sensors are listed for each step of sensor use: initial qualiïŹcation under controlled conditions in the laboratory, preparation of the sensor before deployment, ïŹeld deployment and ïŹnally the sensor recovery. The fundamental principles applied to the laboratory reference method are then reviewed in termsofthecalibrationprotocol,instrumentalinterferences,environmentalinterferences, external controls, and method performance assessment. Data corrections (linearity, sensitivity, drifts, interferences and outliers) are ïŹnally identiïŹed along with the concepts and calculations for qualiïŹcation for both real time and time delayed data. This paper emphasizes the necessity of future collaborations between research groups, referenceaccredited laboratories, and technology developers, to maintain comparability of the concentrationsreportedforthevariousnutrientparametersmeasuredbyinsitusensors
A Kriging and stochastic collocation ensemble for uncertainty quantification in engineering applications
The effects of private equity investors on the governance of firms
Companies that receive external equity typically experience a separation of ownership and control, where owners who are not involved in the company (principals) have to rely on the management team (agents) for achieving expected goals and target levels. Theoretical literature argues that when ownership and control are separated, principals develop governance structures to reduce agency costs and align agentsâ incentives (Berle and Means, 1932; Jensen and Meckling, 1976; Grossman and Hart, 1986; Zingales, 1995). Likewise, optimal financial structure design by financial intermediaries can effectively help to mitigate agency problems by identifying self-enforcing equilibria (Diamond, 1984; Fama and Jensen, 1985; Stiglitz, 1985; Bhattacharya and Thakor, 1993; Barry, 1994).
In general terms, governance and financial devices can be thought of as either internal control mechanisms (such as the board) or external control mechanisms (such as the market for corporate control). An increasingly important external control mechanism affecting the governance of young and fast-growing companies worldwide is the emergence of institutional and private equity investors, as equity owners. Institutional investors have the potential to influence managementâs activities directly through their ownership, and indirectly by trading their shares (Gillan and Starks, 2003). In this respect private equity investors are differentiated from institutional ones in the longer-term view and in the significantly more hands-on approach that they pursue when investing in a portfolio company. As a result, companies backed by private equity investors represent a fruitful environment to investigate the use and efficiency of a multitude of control mechanisms.
The surge over the last 30 years in investment activity by private equity investors at large has given rise to an increased specialization of this class of investors conditional on the risk return profiles associated with different investment and firm life cycle stages. For instance, business angels supporting the archetypical âpaper companyâ start-up face a risk exposure that in terms of both magnitude and characteristics is significantly different from that incurred by a private equity investor acquiring control of a mature company. Yet, investors in this market share common traits such as a value maximization approach, riskâreturn informed decisions, and a deep knowledge of governance mechanisms. As such their influence on portfolio company governance mechanisms is largely similar in terms of depth and breadth. In this chapter we aim at presenting an up-to-date review of the main theoretical contributions and empirical results in this active and growing field of research
Train Commuters' Scheduling Preferences: Evidence from a Large-Scale Peak Avoidance Experiment
The effect of tightly-bound water molecules on scaffold diversity in computer-aided de novo ligand design of CDK2 inhibitors
We have determined the effects that tightly bound water molecules have on the de novo design of cyclin-dependent kinase-2 (CDK2) ligands. In particular, we have analyzed the impact of a specific structural water molecule on the chemical diversity and binding mode of ligands generated through a de novo structure-based ligand generation method in the binding site of CDK2. The tightly bound water molecule modifies the size and shape of the binding site and we have found that it also imposed constraints on the observed binding modes of the generated ligands. This in turn had the indirect effect of reducing the chemical diversity of the underlying molecular scaffolds that were able to bind to the enzyme satisfactorily
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Are researchers deliberately bypassing the technology transfer office? An analysis of TTO awareness
Most universities committed to the commercialization of academic research have established technology transfer offices (TTOs). Nonetheless, many researchers bypass these TTOs and take their inventions directly to the marketplace. While TTO bypassing has typically been portrayed as deliberate and undesirable behavior, we argue that it could be unintentional as many researchers may simply be unaware of the TTOâs existence. Taking an information-processing perspective and using data on 3250 researchers in 24 European universities, we examine researcher attributes associated with TTO awareness. Our evidence confirms that only a minority of researchers are aware of the existence of a TTO at their university. TTO awareness is greater among researchers who possess experience as entrepreneurs, closed many research and consulting contracts with industry partners, conduct research in medicine, engineering or life sciences, or occupy postdoctoral positions. Policy implications of these findings are discussed
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