Abstract. Infrared (IR) cameras based on microbolometer focal plane arrays (FPAs) are the most widely used cameras in thermography. New fields of applications like handheld devices and small distributed sensors benefit from the latest sensor improvements in terms of cost and size reduction. In order to compensate for disturbing influences derived from changing ambient conditions, radiometric cameras use an optical shutter for online recalibration purposes, partially also together with sensor temperature stabilization. For these new applications, IR cameras should consist only of infrared optics, a sensor array, and digital signal processing (DSP). For acceptable measurement uncertainty values without using an optical shutter (shutter-less), the disturbing influences of changing thermal conditions have to be treated based on temperature measurements of the camera interior. We propose a compensation approach based on calibration measurements under controlled ambient conditions. All correction parameters are determined during the calibration process. Without sensor temperature stabilization (TEC-less), the pixel responsivity is also affected by the camera temperature changes and has to be considered separately. This paper presents the details of the compensation procedure and discusses relevant aspects to gain low temperature measurement uncertainty. The residual measurement uncertainty values are compared to the shutter-based compensation approach.

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Objectives. This article explores the extent to which economic development, ethnic and religious fractionalization, domestic governance, and international trade openness affect civil war in postcolonial Asia and Sub‐Saharan Africa (SSA) from 1950 through 1992. Methods. We estimate a set of multivariate logit models with the generalized estimating equation (GEE) method for time‐series cross‐sectional (TSCS) data. Results. Both in Asia and in SSA, civil war is less likely with increased economic development and trade openness, while mixed autocratic‐democratic regimes raise the likelihood that states will experience civil war. Although neither ethnic nor religious fractionalization has any statistically significant effect on civil war in SSA, civil war in Asia is more likely with greater ethnic fractionalization. Conclusions. Despite cross‐regional variation in causes of civil war, economic development and trade openness seem to play a consistent role in reducing civil war.

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Alliances are subject to many scholarly inquiries in international relations and peace research because they are major instruments of foreign and security policies. Since the early work on alliances produced by the Correlates of War (COW) project, there have been significant advances in conceptual, theoretical, and empirical alliance research. New typologies and data permit us to differentiate more thoroughly among a variety of alliance objectives and functions. Furthermore, there has been new theoretical and empirical research on alliance formation, alliance configuration/polarization, effects of alliances on military conflict, connections between alliances and trade, and the economics of alliances. Providing new theoretical approaches, data, and empirical evidence on alliances, this special issue includes articles that address alliance formation, alliance polarization, alliances and democratization, trade among allies, regional economic institutions with alliance obligations, and defense industrial policies of military alliances. The articles in this issue extend our understanding of alliances past the traditional realist balance-of-power framework and encourage further testing and refinement of older alliance arguments and extensions to new theoretical developments.

In this paper we present the next step on the roadmap "system scalability towards an output power above 100 kW", first time presented in 2014 [1]. To take a step forward the optical power of the fiber-coupled diode laser has been increased beyond the power level 40kW. The power conversion efficiency exceeds 40%. The laser contains modules with 4 different wavelengths (960nm, 1020nm, 1040nm, 1060nm) there are two modules for each wavelength polarization multiplexed. After the slow-axis collimation these wavelengths are combined using dense wavelength coupling before focusing onto the fiber endface. The delivery-fiber is an uncoated fiber with a diameter of 2 mm and NA 0.22 corresponding a BPP of 220 mm mrad. In a stability test the laser delivered a constant maximum output power with less than +/- 0.5 % variation over 100h. Further results of the optical properties of the laser will be presented in this paper. This new laser is based on a turn-key industrial platform, allowing straight-forward integration into almost any industrial application, like welding or large area heat treatment. As application examples laser welding of thick sheet metal and pumping of an active fiber will be presented. The footprint of the complete system is 2.8 m(2) with a height below 1.8 m