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Mobility particle size spectrometers often referred to as DMPS (Differential Mobility Particle Sizers) or SMPS (Scanning Mobility Particle Sizers) have found a wide range of applications in atmospheric aerosol research. However, comparability of measurements conducted world-wide is hampered by lack of generally accepted technical standards and guidelines with respect to the instrumental set-up, me

The online-coupled, regional chemistry transport model COSMO-ART is evaluated for periods in all seasons against several measurement datasets to assess its ability to represent gaseous pollutants and ambient aerosol characteristics over the European domain. Measurements used in the comparison include long-term station observations, satellite and ground-based remote sensing products, and complex da

We describe a general-purpose dryer designed for continuous sampling of atmospheric aerosol, where a specified relative humidity (RH) of the sample flow (lower than the atmospheric humidity) is required. It is often prescribed to measure the properties of dried aerosol, for instance for monitoring networks. The specific purpose of our dryer is to dry cloud droplets (maximum diameter approximately

Abstract in UndeterminedContext: Defect reporting is an important part of software development in-vivo, but previous work from open source context suggests that defect reports often have insufficient information for defect fixing. Objective: Our goal was to reproduce and partially replicate one of those open source studies in industrial context to see how well the results could be generalized. Met

The Amazon Basin provides an excellent environment for studying the sources, transformations, and properties of natural aerosol particles and the resulting links between biological processes and climate. With this framework in mind, the Amazonian Aerosol Characterization Experiment (AMAZE-08), carried out from 7 February to 14 March 2008 during the wet season in the central Amazon Basin, sought to

H2SO4 vapor is important for the nucleation of atmospheric aerosols and the growth of ultrafine particles to cloud condensation nuclei (CCN) sizes with important roles in the global aerosol budget and hence planetary radiative forcing. Recent studies have found that reactions of stabilized Criegee intermediates (CIs, formed from the ozonolysis of alkenes) with SO2 may be an important source of H2S

A series of nine radiocarbon measurements obtained at increments of 50 years was used to wiggle match varved sediments in Lake Kalksjon (west central Sweden) to the calendar year time scale provided by the tree-ring-derived radiocarbon calibration curve. The anchor point for a series of 400 varves known to span the '8.2 kyr cold event' was derived from a combination of correlation analysis, Monte

Dating the bottommost section of an ice core is often complicated by strong layer thinning and possible disturbances in the stratigraphy. The radioactive decay of atmospherically produced 36Cl and 10Be can provide age estimates, where traditional methods can no longer be used. In this study, we investigated ice from the bottom of the Skytrain ice core, which was drilled in West Antarctica next to

Ice cores are unique archives of paleo-climate information and require accurate dating for its interpretation. Continuous chronologies are usually based on time markers, stratigraphic matching, and orbital tuning, but often end several meters above bedrock, because extreme thinning and sometimes disturbances in the stratigraphy complicate the identification of climate signals and their alignment w

The research area of climate field reconstructions has developed strongly during the past 20 years, motivated by the need to understand the complex dynamics of the earth system in a changing climate. Climate field reconstructions aim to build a consistent gridded climate reconstruction of different variables, often from a range of climate proxies, using either statistical tools or a climate model

The sun is the most important energy source for the Earth’s climate system, however, influences of solar variations on climate are not fully understood. Studying past solar activity can improve our understanding of what role the sun plays in Earth’s climate. Cosmogenic radionuclides, such as 10Be in ice cores, are powerful tools to reconstruct past solar activity before the period of direct telesc

A novel code construction based on spatially coupled low-density parity-check (SC-LDPC) code chains is presented. The proposed code ensembles are described by graphs in which individual SC-LDPC code chains of various lengths serve as edges. We demonstrate that connecting several appropriately chosen SC-LDPC code chains results in improved iterative decoding thresholds compared to those of a single

Low rank inducing penalties have been proven to successfully uncover fundamental structures considered in computer vision and machine learning; however, such methods generally lead to non-convex optimization problems. Since the resulting objective is non-convex one often resorts to using standard splitting schemes such as Alternating Direction Methods of Multipliers (ADMM), or other subgradient me

In this paper, we derive the exact input/output transfer functions of the optimal a-posteriori probability channel detector for a general ISI channel with erasures. Considering three channel impulse responses of different memory as an example, we compute the BP and MAP thresholds for regular spatially coupled LDPC codes with joint iterative detection and decoding. When we compare the results with

Time-varying spatially coupled low-density parity-check (SC-LDPC) codes with very large period are characterized by significantly better error rate performance and girth properties than their time-invariant counterparts, but the number of parameters they require to be described is usually very large and unpractical. Time-invariant SC-LDPC codes, which can be seen as periodically time-varying codes

Families of asymptotically regular LDPC block code ensembles can be formed by terminating (J, K)-regular protograph-based LDPC convolutional codes. By varying the termination length, we obtain a large selection of LDPC block code ensembles with varying code rates, minimum distance that grows linearly with block length, and capacity approaching iterative decoding thresholds, despite the fact that t

Introduction: There is growing evidence that induction of labor at 41 completed weeks improves neonatal outcome, at least among primiparous women. This study was performed to investigate whether maternal body mass index (BMI) should be considered when deciding on timing of intervention in term pregnancies. Material and methods: The study design was a historical cohort study using data from the Swe

In this paper, we perform a threshold analysis of braided convolutional codes on the additive white Gaussian noise (AWGN) channel. The decoding thresholds are estimated by Monte-Carlo density evolution techniques and compared with approximate thresholds from an erasure channel prediction. The results show that, with spatial coupling, the predicted thresholds are very accurate and quickly approach