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Microwave vs. Millimeter-Wave Propagation Channels: Key Differences and Impact on 5G Cellular Systems

Fifth generation cellular systems will be deployed in the microwave and millimeter–wave (mmWave) frequency bands (i.e., between 0.5–100 GHz). Propagation characteristics at these bands have a fundamental impact on each aspect of the cellular architecture, ranging from equipment design to real-time performance in the field. While we have a reasonable understanding of the propagation characteristics

Uplink Interference Analysis with RF Switching for Lens-Based Millimeter-Wave Systems

In this paper, we take a fundamental look at the interference characteristics of a lens-based millimeter-wave (mmWave) multiuser multiple-input multiple-output system (MU-MIMO) system. We consider a hybrid architecture, implemented via a bank of radio-frequency (RF) switches which perform beam selection followed by low-complexity uplink maximum-ratio combining (MRC) at baseband. Considering a Rotm

Revisiting MMSE Combining for Massive MIMO over Heterogeneous Propagation Channels

We consider a massive multiple-input multiple- output system with minimum-mean-squared-error processing on the uplink. A novel analytical framework is proposed to approximate the instantaneous signal-to-interference-plus-noise- ratio (SINR) of an arbitrary user terminal, as well as, the system sum spectral efficiency. Unlike previous studies, our methodology considers spatially correlated Ricean f

Simple modeling techniques for base-stock inventory systems with state dependent demand rates

In this paper new modeling techniques of (S- 1 , S) inventory systems (continuous review base-stock inventory systems) with state dependent demand rates are proposed. Examples of single-location (S- 1 , S) inventory systems where the demand, experienced by the system, varies due to the state of the system are, e.g., inventory models with partial backorders, inventory models with lost sales, invent

Large-scale and distributed optimization : An introduction

The recent explosion in size and complexity of datasets and the increased availability of computational resources has led us to what is sometimes called the big data era. In many big data fields, mathematical optimization has over the last decade emerged as a vital tool in extracting information from the data sets and creating predictors for unseen data. The large dimension of these data sets and

Biomarkers of Exposure to Pyrimethanil After Controlled Human Experiments

Pyrimethanil (PYM) is a fungicide used pre- and post-harvest on many crops. It has a low acute toxicity but is of toxicological concern because of its antiandrogenic properties. The aim of the current work was to investigate some metabolism and estimate elimination kinetics of PYM in humans after experimental oral and dermal exposure. A liquid chromatography triple quadrupole mass spectrometry (LC

Surgical Site Infections in Dermatologic Surgery- Clinical, diagnostic, and pathogenic aspects

Surgical site infections (SSIs) in dermatologic surge- ry contribute to unwanted healthcare costs and are complications that cause su ering in patients. The aim of this thesis was to explore clinical, diagnos- tic, and pathogenic aspects of SSIs in dermatologic surgery.In study I, we examined bacterial dynamics during normal wound healing and SSIs. We found that quantifying bacteria from wounds wa

Predation-mediated ecosystem services and disservices in agricultural landscapes

Ecological intensification may reduce environmental externalities of agriculture by harnessing biodiversity to benefit regulating ecosystem services. However, to propose management options for the production of such services, there is a need to understand the spatiotemporal dynamics of net effects between ecosystem services and disservices provided by wild organisms across taxonomic groups in rela

Imaging in gynecological disease (14) : clinical and ultrasound characteristics of ovarian clear cell carcinoma

Objective: To describe the clinical and ultrasound characteristics of ovarian pure clear cell carcinoma. Methods: This was a retrospective study involving data from 11 ultrasound centers. From the International Ovarian Tumor Analysis (IOTA) database, 105 patients who had undergone preoperative ultrasound examination by an experienced ultrasound examiner between 1999 and 2016 were identified with a

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Introduction and aim: Hip and knee replacement surgery is very demanding for patients. Medication consumption is further increased by perioperative anxiety. Besides pain killer and anxiolytic medications, patients' recovery can be enhanced by applying therapeutic suggestions, which are easily applicable during the patient-physician communication. Method: In our prospective, randomized, controlled

Intellectual disability and psychotic disorders in children : Association with maternal severe mental illness and exposure to obstetric complications in a whole-population cohort

Objective: Children of mothers with severe mental illness are at significantly increased risk of developing intellectual disability. Obstetric complications are also implicated in the risk for intellectual disability. Moreover, children of mothers with severe mental illness are more likely to be exposed to obstetric complications. The purpose of this study was to examine the independent and joint

An engineered combinatorial module of transcription factors boosts production of monoterpenoid indole alkaloids in Catharanthus roseus

To fend off microbial pathogens and herbivores, plants have evolved a wide range of defense strategies such as physical barriers, or the production of anti-digestive proteins or bioactive specialized metabolites. Accumulation of the latter compounds is often regulated by transcriptional activation of the biosynthesis pathway genes by the phytohormone jasmonate-isoleucine. Here, we used our recentl

Patterns and Drivers of Regional Crop Production in Chad

Jordbruk utgör den största ekonomiska sektorn och har den högsta sysselsättningsgraden i Tchad. Samtidigt så genomgår den hastiga förändringar på grund av populationsökning, institutionella reformer, konflikter i grannländerna, ökande globaliserade handelsnätverk, samt miljöförändringar. Men trots dess betydelse för lokala uppehällen och ekonomisk tillväxt, så är de specifika förändringsmönstrena Agriculture constitutes the largest economic sector and professional occupation in Chad, and is undergoing rapid changes due to processes of population increase, institutional reforms, conflicts in neighbouring countries, increasingly globalized trade networks, and environmental changes. But despite their importance for livelihoods and economic growth, the specific patterns and drivers of change i

The peer context of dieting : The relationship between young adults’ dieting frequency and their friends’ weight-related characteristics

Previous research found that weight-related behaviors and body weight tends to be similar between individuals and peers. Rather little is known how different domains of weight-related behaviors co-evolve in peer networks. Hence, this study explores how young adults’ self-reported dieting relates to perceived body weight and weight control behaviors of their peers. A Swedish two-wave panel survey w

Comprehensive comparison between APOGEE and LAMOST : Radial velocities and atmospheric stellar parameters

Context. In the era of massive spectroscopy surveys, automated stellar parameter pipelines and their validation are extremely important for an efficient scientific exploitation of the spectra. Aims. We undertake a critical and comprehensive comparison of the radial velocities and the main stellar atmosphere parameters for stars in common between the latest data releases from the Apache Point Obser