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The effects of extreme weather events and the resilience of the energy sector have become the subject of regulatory initiatives and ongoing research. We demonstrate the vulnerability of the German power sector to climate change and provide a qualitative and quantitative analysis of emerging risks from two types of extreme weather events: droughts and high temperatures. Our analysis is based on datasets covering temperature and drought data for the last 40 years. We present evidence of a higher frequency of power plant outages as a consequence of droughts and high temperatures. To characterize the vulnerability of the power sector we develop a capacity-adjusted drought index. The results are used to assess the monetary loss of power plant outages due to heatwaves and droughts and losses to consumers due to higher wholesale electricity prices and price volatility. An increasing frequency of such extreme weather events will aggravate the observed problem. Keywords: Electricity, Utilities, Thermal generation, Climate change, Droughts, Weather extremes, Panel data, 1. INTRODUCTION The link between climate change and increasingly frequent extreme weather is gaining the international recognition of policymakers and the attention of the scientific community. The IPCC special report [...]

INTRODUCTION The phrase "no trespassing" conveys a simple message: one may not enter someone else's property without an invitation or the legal authority to do so. Homeowners often use no [...]

We apply state-of-the-art computational geometry methods to the problem of reconstructing a time-varying sea surface from tide gauge records. Our work builds on a recent article by Nitzke et al. (Computers & Geosciences, 157:104920, 2021) who have suggested to learn a triangulation D of a given set of tide gauge stations. The objective is to minimize the misfit of the piecewise linear surface induced by D to a reference surface that has been acquired with satellite altimetry. The authors restricted their search to k-order Delaunay (k-OD) triangulations and used an integer linear program in order to solve the resulting optimization problem. In geometric terms, the input to our problem consists of two sets of points in R2 with elevations: a set S that is to be triangulated, and a set R of reference points. Intuitively, we define the error of a triangulation as the average vertical distance of a point in R to the triangulated surface that is obtained by interpolating elevations of S linearly in each triangle. Our goal is to find the triangulation of S that has minimum error with respect to R. In our work, we prove that the minimum-error triangulation problem is NP-hard and cannot be approximated within any multiplicative factor in polynomial time unless P = NP. At the same time we show that the problem instances that occur in our application (considering sea level data from several hundreds of tide gauge stations worldwide) can be solved relatively fast using dynamic programming when restricted to k-OD triangulations for k = 7. The fast runtime is a result of a set of fixed edges called the k-OD fixed-edge graph. Instances for which the number of connected components of the k-OD fixed-edge graph is small can be solved within few seconds. [ABSTRACT FROM AUTHOR]

A specially designed mass spectrometer which allows for preparative separation of mixtures is described. This mass spectrometer allows for large ion currents, on the order of nanoamperes, to be produced by electrospray and transmitted into a high vacuum. Accumulation of nanomole quantifies of collected and recovered material in several hours is demonstrated. The use of high-velocity ions reduces space charge effects at high ion currents. Separation of mass occurs simultaneously for all ions, providing a 100% duty cycle. The use of a linear dispersion magnet avoids compression at higher m/z ratios. A deceleration lens slows the ions to allow for soft landing at low kinetic energy. The ions are neutralized by ion pairing on an oxidized metal surface. Retractable landing plates allow for easy removal of the separated components.

Research has been conducted on the deuterated sec-alkyl phenyl ethers. Results indicate that there are differences in mass spectra between threo and erythro stereoisomers.

THE WORK of city planners in very broad terms is the determination of best uses of land to promote livable communities. Land-use planning at its best is coordinated with plans [...]

The methyl cation and CF3(super +) attack saturated, acylic ketones to make vibrationally excited adduct ions. The resulting deep-seated rearrangements compete favorably not only with halonium metathesis but also with prompt fragmentations that require only hydride shifts.

The neutral products arising from addition of protonated acetaldehyde to allyltrimethylsilane in the gas-phase is examined. The final neutral product distribution from this gas-phase addition displays kinetic control, which suggest that the adduct ions retain memory of the geometry of initial approach.

Novel methods for incorporation of fluorine into an organic molecule through four member cyclic transition states are presented. The data shows there are minimum of two pathways leading to (CH3)2C-F from propionaldehyde plus CF3 and the fluoride shift product is indistinguishable.

The Speech or Debate Clause of the United States Constitution was put in place to protect and preserve the independence of the legislative branch. The United States Supreme Court has consistently read the Clause broadly to effectuate this purpose, and it has applied the Clause's protections absolutely to ensure that legislators are not questioned by a hostile executive or judiciary in regard to their legislative activities. In recent years, a circuit split has developed regarding whether the Clause provides for a documentary non-disclosure privilege, which would shield legislators from subpoenas or search warrants issued by the executive branch and enforced by the judiciary. The Ninth and Third Circuits have rejected such a documentary non-disclosure privilege, while the D.C. Circuit has consistently reaffirmed its commitment to a broad documentary non-disclosure privilege. Adding further uncertainty to the Clause's protections, the Ninth Circuit has also denied the Clause's protections to legislators involved in negotiations about future legislation. In order to provide clarity to the Clause's privileges, the Supreme Court should adopt a limited documentary non-disclosure privilege and should apply the Clause's protections to non-criminal negotiations in anticipation of future legislation. [ABSTRACT FROM AUTHOR]