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The estimation of the Social Cost of Carbon Dioxide (SC-CO2) is one of the essential purposes of Integrated Assessment Models (IAMs) used in the economics of climate change. One of the most widely used IAMs in this context is DICE. However, the DICE geophysical subsystem fails to account for feedback from the climate subsystem to the carbon subsystem, an effect recently observed in climate physics. This paper investigates how to combine the recently proposed FAIR climate model with the socioeconomic subsystem of DICE. Based on an analysis of its differential-algebraic structure, we propose an efficient discretization of FAIR that provides a new discrete-time hybrid of DICE and FAIR denoted as FAIR-DICE. Finally, we compare estimates of the SC-CO2 obtained with DICE2013 with those obtained via FAIR-DICE., QC 20181106

An investigation was conducted on the ion implantation of high energy (>50 kev) dopant ions into semiconductors for the formation of controlled doped layers. As such, it complements the first report with the emphasis in the present one being on device aspects. A brief resume is given of the range-energy, radiation damage and sputtering concepts which are covered in detail in the first report (AD-635 267). The emphasis in the device work has been on demonstration of implantation concepts rather than on development of highly sophisticated devices. To this end, transistor action in both npn and pnp transistors, n-channel junction FET's GaAs diodes and SiC diodes have been demonstrated. Problems peculiar to ion implantation became evident, and a full appreciation of the steps necessary to overcome them was developed only near the end of the program. Examples of these are contacts to shallow implanted layers and overcompensation effects for double implanted layers, both to which severely hampered bipolar transistor development. However, no basic limitations to any of the proposed implantation concepts were discovered and from the results achieved, it now appears that ion implantation will become an important process for active devices in both Group IV and III-V semiconductors. (Author)

The report describes investigations conducted on the implantation of high energy (>50 kev) dopant ions into semiconductors for the formation of controlled doped layers. Investigations were conducted with B and P ions for p- and n-type layers in Si, SiC and diamond, and Zn and S for p- and n-type layers in GaAs, respectively. Extensive theoretical and experimental work was performed in range-energy relationships in silicon to provide a firm foundation for device work. Results of these investigations were used in the fabrication of active devices, particularly a form of unipolar transistor which lends itself to implantation processing. Successful fabrication was demonstrated and high frequency types are currently being developed. Implanted doped layers were formed in GaAs, SiC and diamond with diode formation demonstrated in GaAs and diamond. Preliminary results indicate that ion implantation may be the best method for handling such materials. (Author)