Miracle-dz/UniFAR-FTUs huggingface dataset:
Decision , Risk and Operations Working Papers Series On customer contact centers with a callback option : Customer decisions , routing rules , and system design

Organizations worldwide use contact centers as an important channel of communication and transaction with their customers. This paper describes a contact center with two channels, one for real-time telephone service, and another for a postponed call-back service offered with a guarantee on the maximum delay until a reply is received. Customers are sensitive to both realtime and call-back delay and their behavior is captured through a probabilistic choice model. The dynamics of the system are modelled as an M/M/N multi-class system. We rigorously justify that as the number of agents increases, the system’s load approaches its maximum processing capacity. Based on this observation, we perform an asymptotic analysis in the many-server, heavy traffic regime to find an asymptotically optimal routing rule, characterize the unique equilibrium regime of the system, approximate the system performance, and finally, propose a staffing rule that picks the minimum number of agents that satisfies a set of operational constraints on the performance of the system.
Poly(N-Isopropylacrylamide)-co-Acrylamide Hydrogels for the Controlled Release of Bromelain from Agroindustrial Residues of Ananas comosus

Abstract This works reports the purification of bromelain extracted from Ananas comosus industrial residues by ethanol purification, its partial characterization from the crude extract as well as the ethanol purified enzyme, and its application onto poly(N-isopropylacrylamide)-co-acrylamide hydrogels. Bromelain was recovered within the 30–70 % ethanol fraction, which achieved a purification factor of 3.12-fold, and yielded more than 90 % of its initial activity. The resulting purified bromelain contained more than 360 U · mg−1, with a maximum working temperature of 60 °C and pH of 8.0. Poly(N-isopropylacrylamide)-co-acrylamide hydrogels presented a swelling rate of 125 %, which was capable of loading 56 % of bromelain from the solution, and was able to release up to 91 % of the retained bromelain. Ethanol precipitation is suitable for bromelain recovery and application onto poly(N-isopropylacrylamide)-co-acrylamide hydrogels based on its processing time and the applied ethanol prices.
Digital correction of mismatches in time-interleaved ADCs for digital-RF receivers

Time-interleaving analog-to-digital converters (ADCs) decreases the required sampling rate for one ADC to achieve gigasamples per second (GS/s) rates. The gain and timing mismatches among the ADCs generate aliasing signals, degrading the spurious-free dynamic range of the time-interleaved ADC (TI-ADC). The conventional digital correction methods for TI-ADCs have not considered application to direct-RF sampling receivers. We present a digital correction method for M-channel TI-ADCs in the receivers. The proposed method employs in-phase/quadrature-phase (I/Q) downconversion mixers and cascaded integrator-comb (CIC) filters in the receiver. This allows the correction circuit (except for mismatch estimation) to have fewer building blocks than the conventional methods: one adder, one multiplier, and no filter. Simulations and measurements show that the proposed method completely reduces the aliasing signals below the noise floor of 4- and 2-channel 12-bit TI-ADCs, respectively.
Misorientations and geometrically necessary dislocations in deformed copper crystals : A microstructural analysis of X-ray rocking curves

Abstract In this study, the deformation-induced misorientations that are typically found in face-centred cubic single crystals deformed in single slip into stage II (and early stage III) of the work-hardening curve are discussed with respect to the experimentally observed broadening of X-ray rocking curves. By making use of well-established empirical relationships between characteristic features of the microstructure and the flow stress, some of the ambiguities of earlier interpretations of rocking curves could be avoided, and relationships between the half-widths of the rocking curves, the density of geometrically necessary dislocations, and the flow stress could be derived for both the tilt misorientations due to the kink bands lying perpendicular to the primary Burgers vector and the twist misorientations originating from the dislocation networks (grids, sheets) lying parallel to the primary glide plane. An evaluation of largely unpublished experimental rocking-curve data obtained on different crystall.
Relationship between Tolerance and Persistence Mechanisms in Acinetobacter baumannii Strains with AbkAB Toxin-Antitoxin System

ABSTRACT The molecular mechanisms of tolerance and persistence associated with several compounds in Acinetobacter baumannii clinical isolates are unknown. Using transcriptomic and phenotypic studies, we found a link between mechanisms of bacterial tolerance to chlorhexidine and the development of persistence in the presence of imipenem in an A. baumannii strain belonging to clinical clone ST-2 (OXA-24 β-lactamase and AbkAB toxin-antitoxin [TA] system carried in a plasmid). Interestingly, the strain A. baumannii ATCC 17978 (AbkAB TA system from plasmid) showed persistence in the presence of imipenem and chlorhexidine.
Affective Instability and Reactivity in Depressed Patients With and Without Borderline Pathology.

The quality of depression in borderline personality disorder (BPD) was reported to differ from that in patients with major depressive disorder (MDD) only. However, little is known about affect dynamics in "borderline-depression. " The authors assessed affective instability and reactivity in 20 MDD patients with BPD and in 21 MDD patients without BPD by Ambulatory Assessment. Participants reported on current affect, daily events, and attribution of affective states to events five times per day over a 7-day period. The results do not indicate higher affective instability in MDD patients with BPD comorbidity. Depressed patients with BPD reported less subjectively perceived affective reactivity, while observed associations between events and affect were not different between groups, except for one finding: In depressed patients with BPD, overall mood was lower after being alone. These findings suggest impaired attribution of mood changes and less tolerance of being alone as specific for depression in BPD.
A Rank based Metric of Anchor Models for Speaker Verification

In this paper, we present an improved method of anchor models for speaker verification. Anchor model is the method that represent a speaker by his relativity of a set of other speakers, called anchor speakers. It was firstly introduced for speaker indexing in large audio database. We suggest a rank based metric for the measurement of speaker character vectors in anchor model. Different from conventional metric methods which consider each anchor speaker equally and compare the log likelihood scores directly, in our method the relative order of anchor speakers is exploited to characterize target speaker. We have taken experiments on the YOHO database. The results show that EER of our method is 13.29% lower than that of conventional metric. Also, our method is more robust against the mismatching between test set and anchor set
Architecture for Reliable Scan-Dump in the Presence of Multiple Asynchronous Clock Domains in FPGA SoCs

Latest SOC trends include multiple asynchronous clock domains, each covering large silicon areas. Clock-Stop & State-Dump (CSSD) is a commonly used silicon debug technique that relies on stopping clocks and reconfiguring flip-flops as one or more scan chains. This paper describes an architecture for stopping clocks deterministically to allow safe state preservation before reconfiguring a circuit. Conditions for determinism are defined and a design IP to implement CSSD is described. Considerations for supporting an IP-SOC design methodology are also specified. The design was implemented and validated in Xilinx' 16nm FPGA family.
Duration of depressive symptoms and mortality risk: the English Longitudinal Study of Ageing (ELSA)

Background The relationship between the duration of depressive symptoms and mortality remains poorly understood. Aims To examine whether the duration of depressive symptoms is associated with mortality risk. Method Data (n = 9560) came from the English Longitudinal Study of Ageing (ELSA). We assessed depressive symptom duration as the sum of examinations with an eight-item Center for Epidemiologic Studies Depression Scale score of ⩾3; we ascertained mortality from linking our data to a national register. Results Relative to those participants who never reported symptoms, the age- and gender-adjusted hazard ratios for elevated depressive symptoms over 1, 2, 3 and 4 examinations were 1.41 (95% CI 1.15–1.74), 1.80 (95% CI 1.44–2.26), 1.97 (95% CI 1.57–2.47) and 2.48 (95% CI 1.90–3.23), respectively (P for trend <0.001). This graded association can be explained largely by differences in physical activity, cognitive function, functional impairments and physical illness. Conclusions In this cohort of older adults, the duration of depressive symptoms was associated with mortality in a dose–response manner.
Position-controlled selective area growth of Ga-polar GaN nanocolumns by molecular beam epitaxy

This thesis focuses on the position-controlled selective area growth of Ga-polar GaN nanocolumns by molecular beam epitaxy. Part I of this thesis reviews the theoretical background which is considered to be vital for the understanding of this thesis. Furthermore, the performed research will be motivated in detail. Chapter 2 summarizes important basic physical properties of GaN. General aspects which are of importance concerning the growth of GaN by molecular beam epitaxy are discussed in Chapter 3. The growth of GaN nanocolumns by molecular beam epitaxy will be topic of discussion in Chapter 4. The last chapter of this part (Chapter 5) summarizes the patterning and characterization techniques which have been used in this thesis. Part II presents results on the selective area growth of GaN nanocolumns, as well as on the structural and optical properties of these columns. Chapter 6 describes the route towards successful selective area growth in detail and summarizes optimized growth conditions. In the following Chapter 7, the selective area growth is investigated. First, a kinetic description, with focus on Ga adatom surface processes which have a strong impact on the nanocolumn axial growth rate, will be used. In addition, it will be shown that the approach of selective area growth is indeed suited to obtain arrayed, semipolar GaN templates. The second section of this chapter presents results on the morphology of the nanocolumns and the polarity, i.e. whether the crystallographic growth direction is along [0001] or antiparallel to this direction along [000-1]. The last section of this chapter discusses the distinct morphology of the GaN columns in the framework of equilibrium thermodynamics. Chapter 8 presents results on the structural properties of the columns. These comprise the crystal quality in general, and the presence of dislocations and extended defects. In addition, the growth of III−N semipolar multi-quantum wells will be presented. The optical properties of the selectively grown GaN nanocolumns will be assessed in Chapter 9 and furthermore correlated with the structural properties. Single GaN nanocolumns are subject of investigation, as well as ensembles of nanocolumns. Part III summarizes the main achievements and conclusions of this work. Based on the results of this thesis, an outlook provides proposals on the future research on selective area growth of GaN nanocolumns by molecular beam epitaxy.
Hand posture and gesture recognition using MYO armband and spectral collaborative representation based classification

In this paper, we propose the use of Collaborative based Representation in Spectral Domain to recognize the postures and gestures from the Electromyography (EMG) recordings acquired by a recently introduced sensor; Thalmic Labs' MYO armband. The recognition accuracy obtained for a set of six hand gestures and postures is promising with an accuracy over 97 % which is a competent result in the related literature. The algorithms are developed for creating an intuitive human machine interface for navigating a robotic wheelchair.
Analysis of the time-resolved magneto-optical Kerr effect for ultrafast magnetization dynamics in ferromagnetic thin films

We discuss fundamental aspects of laser-induced ultrafast demagnetization probed by the time-resolved magneto-optical Kerr effect (MOKE). Studying thin Fe films on MgO substrate in the absence of electronic transport, we demonstrate how to disentangle pump-induced variations of magnetization and magneto-optical coefficients. We provide a mathematical formalism for retrieving genuine laser-induced magnetization dynamics and discuss its applicability in real experimental situations. We further stress the importance of temporal resolution achieved in the experiments and argue that measurements of both time-resolved MOKE rotation and ellipticity are needed for the correct assessment of magnetization dynamics on sub-picosecond timescales. The framework developed here sheds light onto the details of the time-resolved MOKE technique and contributes to the understanding of the interplay between ultrafast laser-induced optical and magnetic effects.
Investigating automatic vectorization for real-time 3D scene understanding

Simultaneous Localization And Mapping (SLAM) is the problem of building a representation of a geometric space while simultaneously estimating the observer's location within the space. While this seems to be a chicken-and-egg problem, several algorithms have appeared in the last decades that approximately and iteratively solve this problem. SLAM algorithms are tailored to the available resources, hence aimed at balancing the precision of the map with the constraints that the computational platform imposes and the desire to obtain real-time results. Working with KinectFusion, an established SLAM implementation, we explore in this work the vectorization opportunities present in this scenario, with the goal of using the CPU to its full potential. Using ISPC, an automatic vectorization tool, we produce a partially vectorized version of KinectFusion. Along the way we explore a number of optimization strategies, among which tiling to exploit ray-coherence and outer loop vectorization, obtaining up to 4x speed-up over the baseline on an 8-wide vector machine.
Rewriting XPath Queries Using Materialized Views

As a simple XML query language but with enough expressive power, XPath has become very popular. To expedite evaluation of XPath queries, we consider the problem of rewriting XPath queries using materialized XPath views. This problem is very important and arises not only from query optimization in server side but also from semantic caching in client side. We consider the problem of deciding whether there exists a rewriting of a query using XPath views and the problem of finding minimal rewritings. We first consider those two problems for a very practical XPath fragment containing the descendent, child, wildcard and branch features. We show that the rewriting existence problem is coNP-hard and the problem of finding minimal rewritings is Σp3. We also consider those two rewriting problems for three subclasses of this XPath fragment, each of which contains child feature and two of descendent, wildcard and branch features, and show that both rewriting problems can be polynomially solved. Finally, we give an algorithm for finding minimal rewritings, which is sound for the XPath fragment, but is also complete and runs in polynomial time for its three subclasses.
Measurement and Analysis of LTE Cell Range and Downlink Throughput in Suburban Area

This study used the measured data in the Kenting Spring Scream activity region, the mean cell range corresponding to each MCS was 0.39 km~1.99 km from MCS (0) to MCS (28), and the overall mean MCS cell range was 0.93 km. The measured value of the LTE cell range will be an important step to calculate the coverage probability of the real on-site LTE network. The measured data analysis results showed that the mean Downlink (DL) throughput corresponding to each MCS was 10.13 Mb/s~45.21Mb/s within MCS (0)~MCS (28), and the overall MCS mean DL throughput was 18.69 Mb/s. The mean SINR corresponding to each MCS was -1.18dB~22.85dB within MCS (0)~MCS (28), and the overall mean MCS SINR was about 10.05 dB. The mean RSRP for each MCS was -95.79 dBm to -70.79dBm within MCS (0)~MCS (28), and the overall mean MCS RSRP was about -85.65 dBm. Finally, the normalized 3GPP theoretical values and the measured values are compared and discussed.
A pilot study: Can the UFOV assessment be used as a repeated measure to determine timing of on‐road assessment in stroke?

BACKGROUND/AIMS Useful Field of View scores are predictive of on-road performance post-stroke. No objective data exist to determine if the Useful Field of View (UFOV) assessment can be used as a repeated measure in the post-stroke population to determine timing of occupational therapy on-road assessment as recovery occurs. The aims of this study were to determine whether there is a practice effect if the UFOV is administered at one, two and three months' post-stroke and to assess optimal time post-stroke to refer to an on-road assessment. METHOD Forty-two participants, 17 men (40.5%), with a mean age of 71 years (SD 9.33) were randomly allocated to 1. Assessment group - UFOV at one, two and three months' post-stroke, 2. Control group-UFOV at three months' post-stroke. Parametric and non-parametric tests were utilised depending on data distribution. RESULTS No significance was found between; three months' subtest 1 (P = 0.463), three months' subtest 2 (P = 0.729) and three months' subtest 3 (P = 0.534) between the assessment and control groups. Both group's scores were combined to examine pass/fail rates of UFOV assessment to indicate timing of referral to on-road assessments. At one month, 16.9% stroke survivors passed the UFOV, when reassessed at three months 69.1% passed and 28.6% again failed. CONCLUSION Improvements in scores at one month intervals over three months are due to improvements in abilities assessed by the UFOV as no practice effect was found to influence scores. UFOV scores performed at monthly intervals post-stroke can be used to guide the timing of an occupational therapy on-road assessment, with an increased likelihood of passing, as recovery occurs. This repeated use of the UFOV assessment can assist referral practices that best utilise driving rehabilitation programmes. Larger studies need to be conducted to confirm these results.
Targeting Focal Adhesion Kinase and Resistance to mTOR Inhibition in Pancreatic Neuroendocrine Tumors.

BACKGROUND Focal adhesion kinase (FAK) mediates survival of normal pancreatic islets through activation of AKT. Upon malignant transformation of islet cells into pancreatic neuroendocrine tumors (PanNETs), AKT is frequently overexpressed and mutations in the AKT/mTOR pathway are detected. Because mTOR inhibitors rarely induce PanNET tumor regression, partly because of feedback activation of AKT, novel combination strategies are needed to target FAK/AKT/mTOR signaling. METHODS We characterized the activation of FAK in PanNETs using immunohistochemistry and Western blot analysis and tested the FAK inhibitor PF-04554878 in human PanNET cells in vitro and in vivo (at least three mice per group). In addition, we evaluated the effect of combined FAK and mTOR inhibition on PanNET viability and apoptosis. All statistical tests were two-sided. RESULTS We found that FAK is overexpressed and hyperphosphorylated in human PanNETs and that PF-04554878 strongly inhibited FAK (Tyr397) autophosphorylation in a dose-dependent manner. We found that PF-04554878 inhibited cell proliferation and clonogenicity and induced apoptosis in PanNET cells. Moreover, oral administration of PF-04554878 statistically significantly reduced tumor growth in a patient-derived xenograft model of PanNET (P = .02) and in a human PanNET xenograft model of peritoneal carcinomatosis (P = .03). Importantly, PF-04554878 synergized with the mTOR inhibitor everolimus by preventing feedback AKT activation. CONCLUSIONS We demonstrate for the first time that FAK is overexpressed in PanNETs and that inhibition of FAK activity induces apoptosis and inhibits PanNET proliferation. We found that the novel FAK inhibitor PF-04554878 synergizes with everolimus, a US Food and Drug Administration-approved agent for PanNETs. Our findings warrant the clinical investigation of combined FAK and mTOR inhibition in PanNETs.
A Novel MIMO - OFDM Technique for Improving Wireless Communications System Performance based on SF-BC

In this work, the author implemented a NOVEL technique of multiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) based on space frequency block coding (SF-BC). Where, the implemented code is designed based on the QOC using the techniques of the reconfigurable antennas. The proposed system is implemented using MATLAB program, and the results showing best performance of a wireless communications system of higher coding gain and diversity.
Focusing in Algorithm Explanation

Algorithm animation attempts to explain an algorithm by visualizing interesting events of the execution of the implemented algorithm on some sample input. Algorithm explanation describes the algorithm on some adequate level of abstraction, states invariants, explains how important steps of the algorithm preserve the invariants, and abstracts from the input data up to the relevant properties. It uses a small focus onto the execution state. This paper is concerned with the explanation of algorithms on linked data structures. The thesis of the paper is that shape analysis of such algorithms produces abstract representations of such data structures, which focus on the "active" parts, i.e., the parts of the data structures, which the algorithm can access during it's next steps. The paper presents a concept of visually executing an algorithm on these abstract representations of data.
Visualizing the network of software agents for verification of Multiagent Systems

The verification of Multiagent Systems (MAS) and Distributed Software Systems (DSS) has taken a special attention due to the growing demand of having DSS in recent years. The distributed functionality and lack of having a central control in MAS and DSS may cause to emerge new behaviors in the execution time. This unexpected behavior which was not seen in the requirements is known as emergent behavior and may cause irreparable damages. Detection of these emergent behaviors is more valuable and cost effective in the early phases compared to detecting them after the deployment. In this paper we propose a new technique for the detection of a specific type of emergent behavior in the design phase. We take the advantage of social network visualization in this method. The novelty and direct advantage of this technique is presenting the exact point and cause of emergent behavior.