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Laser scanning is increasingly used in many three‐dimensional (3‐D) measurement and modeling applications. It is the latest technique used in 3‐D measurement, and is becoming increasingly important within a number of applications. However, many applications require photogrammetric data in addition to laser scanning data. The purpose of this paper is to present a range and image sensor combination for three‐dimensional reconstruction of objects or scenes.

In this study, a Nikon D80 camera was mounted on an Ilris 3D laser scanner and CPP was estimated according to the laser scanner coordinate system. The estimated CPP was controlled using three different methods which were developed in this study and a sample application as coloring of point cloud using image taken by the camera mounted on the laser scanner was performed.

It was found that when a high‐resolution camera is mounted on laser scanners, camera position parameters (CPP) should be estimated very accurately with respect to the laser scanner coordinate system.

The paper shows that the combination of high‐resolution camera and laser scanners should be used for more accurate and efficient results in 3D modeling applications.

A solution to increase the energy production rate of the wind turbine is proposed by forcing more air to move through the turbine working section. This can be achieved by equipping the rotor with a diffusing channel ended with a brim (diffuser augmented wind turbine – DAWT). The purpose of this paper is to design an experimental stand and perform the measurements of velocity vector fields through the diffuser and power characteristic of the wind turbine.

The experiments were carried out in a small subsonic wind tunnel at the Institute of Turbomachinery, Lodz University of Technology. An experimental stand design process as well as measurement results are presented. Model size sensitivity study was performed at the beginning. The experimental campaign consisted of velocity measurements by means of particle image velocimetry (PIV) and pneumatic pitot probe as well as torque and rotational velocity measurements.

Characteristics (power coefficient vs tip speed ratio) of the bare and shrouded wind turbine were obtained. The results show an increase in the wind turbine power up to 70-75 per cent by shrouding the rotor with a diffuser. The mechanisms responsible for such a power increase were well explained by the PIV and pneumatic measurement results revealing the nature of the flow through the diffuser.

Experimental stand for wind turbine rotor testing is of a preliminary character. Most optimal methodology for obtaining power characteristic should be determined now. Presented results can serve as good input for choice of stable and reliable control system of wind turbine operational parameters.

A 3 kW DAWT is being developed at the Institute of Turbomachinery, Lodz University of Technology. Aim of the study is to design a compact and smart wind turbine optimised for low wind speed conditions. Developed wind turbine has a potential to be used as an effective element within a net of distributed generation, e.g. for domestic use.

Research carried out is the continuation of theoretical study began in 1970s. It was also inspired by practical solutions proposed by Japanese researchers few years ago. Presented paper is the summary of work devoted to optimisation of the DAWT for wind conditions in the region. Original solution has been applied, e.g. for experimental stand design (3D printing application).

The purpose of this paper is to propose a gauge for the convergence of the deterministic particle swarm optimization (PSO) algorithm to obtain an optimum upper bound for PSO algorithm and also developing a precise equation for predicting the rock fragmentation, as important aims in surface mines.

In this study, a database including 80 sets of data was collected from 80 blasting events in Shur river dam region, in Iran. The values of maximum charge per delay (W), burden (B), spacing (S), stemming (ST), powder factor (PF), rock mass rating (RMR) and D80, as a standard for evaluating the fragmentation, were measured. To check the performance of the proposed PSO models, artificial neural network was also developed. Accuracy of the developed models was evaluated using several statistical evaluation criteria, such as variance account for, R-square (R²) and root mean square error.

Finding the upper bounds for the difference between the position and the best position of particles in PSO algorithm and also developing a precise equation for predicting the rock fragmentation, as important aims in surface mines.

For the first time, the convergence of the deterministic PSO is studied in this study without using the stagnation or the weak chaotic assumption. The authors also studied application of PSO inpredicting rock fragmentation.

The application of weather derivatives in hedging crop yield risk is gaining more interest. However, the further development of weather derivatives – particularly exchange-traded – in the agricultural sector has been impeded by concerns over their hedging performance. The purpose of this paper is to develop a new framework to derive the optimal hedging strategy and evaluate hedging effectiveness.

This framework incorporates a stochastic temperature model, a crop yield model, a risk-neutral pricing method and a profit optimization procedure. Based on a large number of simulated scenarios, the authors study crop yield hedge for a future year. The authors allow the hedger to choose from different types of exchange-traded weather derivatives, and examine the impact of various factors on the optimal hedging strategy.

The analysis shows that hedging objective, pricing method and geographical location of the hedged exposure all play important roles in choosing the best hedging strategy and assessing hedging effectiveness.

This framework is forward-looking, because it focusses on the crop yield hedge for a future year rather than on the historical hedging effectiveness often studied in literature. It utilizes the most up-to-date information related to temperature and crop yield, and hence produces a hedging strategy which is more relevant to the year under consideration.

A growing body of research has identified time pressure as a key driver of cybersecurity (CS) risks and vulnerabilities. To strengthen CS, organizations use CS documents (e.g. best practices, guidelines and policies) intended to strengthen CS. The purpose of this paper is to provide an overview of how specifically time pressure is addressed by CS documents.

The authors conducted a systematic search for CS documents followed by a content analysis of the identified documents. First, the authors carried out a systematic Web search and identified 92 formal and informal CS documents (e.g. security policies, procedures, guidelines, manuals and best practices). Second, they systematically analyzed the resulting documents (n = 92), using a structured approach of data familiarization and low-/high-level coding for the identification and interpretation of themes. Based on this analysis, the authors formulated a conceptual framework that captures the sources and effects of time pressure along the themes of industry, operations and users.

The authors developed a conceptual framework that outlines the role of time pressure for the CS industry, threats and operations. This provides a shared frame of reference for researchers and practitioners to understand the antecedents and consequences of time pressure in the organizational CS context.

While the analyzed documents acknowledge time pressure as an important factor for CS, the documents provide limited information on how to respond to these concerns. Future research could, hence, consult with CS experts and policymakers to inform the development of effective guidelines and policies on how to address time pressure in the identified areas. A dedicated analysis within each area will allow to investigate the corresponding aspects of time pressure in-depth along with a consideration for targeted guidelines and policies. Last, note that a differentiation between CS document types (e.g. formal vs informal and global vs regional) was beyond the scope of this paper and may be investigated by future work.

This study makes three main contributions to the CS literature. First, this study broadens the understanding of the role of time pressure in CS to consider the organizational perspective along the themes of industry, threats and operations. Second, this study provides the first comprehensive assessment of how organizations address time pressure through CS documents, and how this compares to existing research in academic literature. Third, by developing a conceptual framework, this study provides a shared frame of reference for researchers and practitioners to further develop CS documents that consider time pressure’s role in secure behavior.

I have been asked to explore how James Buchanan’s work on public finance and constitutional political economy might have emerged out of themes present in Frank Knight’s oeuvre, especially his Risk Uncertainty, and Profit. Buchanan’s body of work has inspired the development of a style of political economy sometimes described as Virginia or Constitutional Political Economy to distinguish it from the Chicago Political Economy with which George Stigler is associated, and with Stigler and Buchanan both being students of Knight. While Buchanan, unlike Stigler, did not write his dissertation under Knight’s supervision, this is a minor distinction because Buchanan regarded Knight as his de facto supervisor even though Roy Blough was his de jure supervisor. The author explains how Knight’s scholarly oeuvre can in large measure be detected in Buchanan’s effort to fashion an alternative approach to public finance and to articulate the field of study now called constitutional political economy.

This study first replicates, then perturbs, the centipede game as implemented by McKelvey and Palfrey (1992). It is thus both a replication study and an original research study. We use controlled laboratory experiments, with computer interfaces for each treatment, anonymous round-robin matching among the subjects across rounds, multiple (10) rounds within each treatment, and incremental changes between adjacent treatments allowing for an assessment of effects at the margin of different game configurations. We find unraveling to the subgame perfect equilibrium somewhat faster than did McKelvey and Palfrey (1992), when using their exact design. Perturbations to that design show that setting non-taker payoffs to zero induces earlier unraveling, as does the use of higher stakes (as in Murphy, Rapoport, and Parco (2006), and Rapoport, Stein, Parco, and Nicholas (2003), respectively). Other, subsequent perturbations show: that there is at most a subtle effect associated with using a 10-second timer with a default move, relative to untimed active moves; and that clock format versus tree format has a minimal effect in common information, unchanging payoff-parameterization environments. We verify the robustness of some key past findings in real-time games. We also explore in a common information environment, the effect of design features previously used in independent private values settings; here we find new evidence that features which might modulate information acquisition and/or processing in an independent private values setting may not restrict behavior in a common information setting.

Previous studies showed mixed results as to the cause of myopic loss aversion (MLA). This paper reexamines the main driver of MLA, considering two factors from previous studies and an additional factor.

Experimentally investigate whether flexibility of investment, frequency of information feedback, or timing of decision cause MLA.

Timing of decision and flexibility of investment explain most differences in subject behavior. Frequency of information feedback makes only a marginal contribution.

The differences in subject behavior can be interpreted by a shift in their reference points depending on the difference in flexibility of investment, frequency of information feedback, or timing of decision.

We replicate and extend the social history treatment of the Berg, Dickhaut, and McCabe (1995) investment game, to further document how the reporting of financial history influences how laboratory societies organize themselves over time. We replicate Berg et al. (1995) by conducting a No History and a Financial History session to determine whether a report summarizing the financial transactions of a previous experimental session will significantly reduce entropy in the amounts sent by Investors and returned by Stewards in the investment game, as Berg et al. (1995) found. We extend Berg et al. (1995) in two ways. First, we conduct a total of five sessions (one No History and four Financial History sessions). Second, we introduce Shannon’s (1948) measure of entropy from information theory to assess whether the introduction of financial transaction history reduces the amount of dispersion in the amounts invested and returned across generations of players. Results across sessions indicate that entropy declined in both the amounts sent by Investors and the percentage returned by Stewards, but these patterns are weaker and mixed compared to those in the Berg et al. (1995) study. Additional research is needed to test how initial conditions, path dependencies, actors’ strategic reasoning about others’ behavior, multiple sessions, and communication may mediate the impact of financial history. The study’s multiple successive Financial History sessions and entropy measure are new to the investment game literature.

The authors construct an index of economic policy uncertainty (EPU) for Greece using textual analysis and analyze its role in the 10-year Greek economic crisis.

To identify the causal relationship between various measures of economic activity and EPU in Greece, the authors use a sophisticated “shock-based” structural vector autoregressive identification scheme. Additionally, the authors use two additional models to ensure the robustness of the results.

EPU is negatively associated with domestic economic activity and economic sentiment, and positively with bond credit spreads. EPU is also estimated to have prolonged the crisis even in periods when macroeconomic imbalances were cured. The results are robust across various model specifications and different proxies of economic activity.

Brunnermeier (2017) observed that uncertainty may be central to understanding the evolution of the Greek crisis. Yet little attention has been paid to policy uncertainty in the existing long and growing literature on the Greek crisis. The authors attempt to fill this gap.