bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimize Energy Efficiency of Quadrotors Via Arm Rotation
Authors: Xiong Hao , Hu Jin , Diao Xiumin
Published: March 2019

Quadrotors have been used in many areas such as cargo transportation, agriculture, and search and rescue. The low energy density of power sources and the low energy efficiency of quadrotors have prevented quadrotors from a wider range of applications where a large payload has to be carried or long flight time is required. This paper optimizes the energy efficiency of a quadrotor via rotating its arms to proper positions calculated based on the dynamics model of the quadrotor and the power–thrust curve of rotors. The conditions that a quadrotor in steady-state can achieve the optimal energy efficiency are mathematically derived and the energy efficiency of a quadrotor in various scenarios is analyzed. Based on the analysis, an arm-rotation approach is proposed to optimize the energy efficiency of a quadrotor with a center-of-gravity offset in steady hovering. It is shown with simulation that an example quadrotor with rotatable arms can save up to 13% of energy. Experiments show that the same example quadrotor can save even more energy in practice, owing to the byproduct of the arm-rotation approach.
Effect of Oil Supply Pressure on the Force Coefficients of a Squeeze Film Damper Sealed With Piston Rings
Authors: Jeung Sung-Hwa , San Andrés Luis , Den Sean , Koo Bonjin
Published: March 2019

Squeeze film dampers (SFDs) aid to both reduce rotor dynamic displacements and to increase system stability. Dampers sealed with piston rings (PR), common in aircraft engines, are proven to boost damping generation, reduce lubricant flow demand, and prevent air ingestion. This paper presents the estimation of force coefficients in a short length SFD, PR sealed, and supplied with a light lubricant at two feed pressures, Pin-1 ∼ 0.69 barg and Pin-2 ∼ 2.76 barg, i.e., low and high. Two pairs of PRs are installed in the test SFD, one set has flow conductance CS1 = 0.56 LPM/bar, whereas the other pair has CS2 = 0.89 LPM/bar. The second set leaks more as it has a larger slit gap. Dynamic load tests show that both dampers, having seal flow conductances differing by 60%, produce damping and added mass coefficients of similar magnitude, differing by at most 20%. Other experiments quantify the effect of lubricant supply pressure, Pin-1 and Pin-2, on the dynamic film pressure and force coefficients of the PR-SFD. The damper configuration with CS1 and operating with the high Pin-2 shows ∼20% more damping and added mass coefficients compared with test results for the damper supplied with Pin-1. Film pressure measurements show that the air ingestion and oil vapor cavitation coexist for operation at the low Pin-1. Computational predictions accounting for the feed holes in the physical model agree with the experimental coefficients. On the other hand, predictions from classical formulas for an idealized damper geometry, fully sealed at its ends, largely overpredict the measured force coefficients.
Exploring the Effect of Dihedral Energy on the Nonlinear Mechanics of the Carbon Nanotubes Using a Multiscale Modeling
Authors: Singh Sandeep
Published: March 2019

A hierarchical multiscale finite element model is employed to investigate the effect of dihedral energy term on the numerical simulation of two-dimensional materials. The numerical examples of the carbon nanotubes and graphene sheets are studied employing a refined constitutive model in conjunction with a multiscale finite element method. The constitutive law refined with the greater accuracy on the bending modulus using second generation reactive empirical bond order potential with dihedral energy term is employed to investigate the linear and nonlinear response of the carbon nanotubes incorporating material and Green–Lagrange geometric nonlinearities. The inclusion of the dihedral energy term predicts bending modulus close to those of through first principle calculations. The deformations at the nanoscale and macroscopic scales are related through the Cauchy–Born rule. The effect of the dihedral energy term on the response of the carbon nanotubes is studied in detail. The governing equation of motion for the carbon nanotubes is formulated through Hamilton’s energy principle. The spatial approximation of the carbon nanotubes at the continuum scale is attained through the finite element method. The membrane locking in the circumferential strain is eliminated through the membrane consistent interpolation functions obtained through the least-square method.
Numerical and Experimental Investigation on the Feasibility of Horizontal Drilling With a New Type of Jet Mill Bit
Authors: Cao Tong , Yu Kaian , Chen Xuyue , Gao Deli , Zhu Hongwu , Luo YunQing
Published: March 2019

Recently, a new type of jet mill bit (JMB) has been introduced to improve the cutting transport efficiency in horizontal drilling by comminuting cuttings into dust-like particles immediately after the cuttings are generated. To promote the application of JMBs in the field, in this work, JMBs were further improved by including junk slots (JS) all around to allow cuttings to flow through the annulus and thereby prevent sticking from occurring while tripping out. Moreover, numerical and experimental investigations on the feasibility of horizontal drilling with the new type of JMB were carried out. The finite element method was used to analyze the strength of the new type of JMB, and flow field simulation analysis was also performed for JMBs with different sizes of JS. The simulation results indicated that the weakest point of the JMB was located at the bit connection instead of the bit frame, and it was demonstrated that the structural strength of the JMB met the requirements of actual working conditions. The JMB JS had a negative effect on promoting the upward return of cuttings from the bottom of the hole, and the larger the slot sizes were, the more negative the effects. Through a trip-out experiment with the new type of JMB, this paper studied the influence of the slot size on the trip-out process safety. The experimental results indicated that the minimum safe slot width was 60 mm. Finally, in a synthesis of the simulation and experimental results, the reasonable range of slot width was determined to be 60–70 mm; the aforementioned range was the most suitable for the bit based on safety and efficiency considerations. This paper provides guidance for the improvement and application of JMBs.
Advanced Exergetic Assessment of a Vapor Compression Cycle With Alternative Refrigerants
Authors: Modi Nishant , Pandya Bhargav , Patel Jatin , Mudgal Anurag
Published: March 2019

The present study compares the thermal performance of various alternative refrigerants with conventional refrigerant operating on a vapor compression cycle with energetic, exergetic, and advanced exergetic approaches. Appropriate alternative refrigerants are selected for the analysis, and R1234yf is recommended as the best suitable refrigerant to replace the existing refrigerants. By splitting the exergy destruction into endogenous and unavoidable, endogenous and avoidable, exogenous and unavoidable, and exogenous and avoidable parts, an advanced exergy method depicts the real potentials for the improvement in the thermal system. Moreover, a traditional exergy method prefers condenser for performance improvement as it has 18.48% higher exergy destruction than evaporator, whereas the advanced exergy method proposes evaporator rather than condenser since its endogenous and avoidable destruction part is 26.38% more than condenser for R1234yf refrigerant.
A Comprehensive Kinetics Library for Simulating the Combustion of Automotive Fuels
Authors: Naik Chitralkumar V. , Puduppakkam Karthik V. , Meeks Ellen
Published: March 2019

We have developed a surrogate blending methodology to identify surrogates with a desired degree of complexity. Along with estimation methods for various physical and chemical properties for fuel blends, we have assembled and developed a rich library of over 60 fuel components. The components cover a carbon number range from 1 to 20, and chemical classes including linear and branched alkanes, olefins, aromatics with one and two rings, alcohols, esters, and ethers. With these, surrogates can be formulated to represent most gasoline, diesel, gaseous fuels, renewable fuels, and several additives. As part of the library, we have assembled self-consistent and detailed reaction mechanisms for all the components, as well as for emissions including NOx and polycyclic aromatic hydrocarbons and a detailed soot-surface mechanism. An extensive validation suite has been used to improve the kinetics database such that good predictions and agreement to data are achieved for the fuel components and fuel-component blends, within experimental uncertainties. This effectively eliminates the need to tune specific rate parameters when employing the kinetics mechanisms in combustion simulations. For engine simulations, the master mechanisms have been reduced using a combination of available reduction methods while strictly controlling the error tolerances for targeted predictions. This approach has resulted in small mechanisms for efficiently incorporating the validated kinetics into computational fluid dynamics (CFD) applications. The surrogate formulation methodology, the comprehensive fuel library, and mechanism reduction strategies suggested in this work allow the use of CFD to explore design concepts and fuel effects in engines with reliable predictions.
Grid-free compressive mode extraction
Authors: Park Yongsung , Gerstoft Peter , Seong Woojae
Published: March 2019

A grid-free compressive sensing (CS) based method for extracting the normal modes of acoustic propagation in the ocean waveguide from vertical line array (VLA) data is presented. Extracting the normal modes involves the estimation of mode horizontal wavenumbers and the corresponding mode shapes. Sparse representation of the waveguide propagation using modes at discrete horizontal wavenumbers enables CS to be applied. Grid-free CS, based on group total-variation norm minimization, is adopted to mitigate the issues of the wavenumber search grid discretization in the conventional CS. In addition, the suggested method can process multiple sensor data jointly, which improves performance in estimation over single sensor data processing. The method here uses data on a VLA from a source at several ranges, and processes the multiple sensor data at different depths jointly. The grid-free CS extracts the mode wavenumbers and shapes even with no a priori environmental knowledge, a partial water column spanning array data, and without the mode orthogonality condition. The approach is illustrated by numerical simulations and experimental SWellEx-96 (shallow water evaluation cell experiment 1996) data.
A hidden state in the turnover of a functioning membrane protein complex
Authors: Shi Hui , Ma Shuwen , Zhang Rongjing , Yuan Junhua
Published: March 2019

We discovered a hidden state in the turnover of the torque-generating units of the bacterial flagellar rotary motor.
A previously unrecognized source of the O
2
Atmospheric band emission in Earth’s nightglow
Authors: Kalogerakis Konstantinos S.
Published: March 2019

Energy transfer from vibrationally excited OH to O atoms leads to enhanced O
2
nightglow in Earth’s upper atmosphere.
Newly developed reversible MAO-B inhibitor circumvents the shortcomings of irreversible inhibitors in Alzheimer’s disease
Authors: Park Jong-Hyun , Ju Yeon Ha , Choi Ji Won , Song Hyo Jung , Jang Bo Ko , Woo Junsung , Chun Heejung , Kim Hyeon Jeong , Shin Su Jeong , Yarishkin Oleg , Jo Seonmi , Park Mijeong , Yeon Seul Ki , Kim Siwon , Kim Jeongyeon , Nam Min-Ho , Londhe Ashwini M. , Kim Jina , Cho Sung Jin , Cho Suengmok , Lee Changho , Hwang Sung Yeoun , Kim Sang Wook , Oh Soo-Jin , Cho Jeiwon , Pae Ae Nim , Lee C. Justin , Park Ki Duk
Published: March 2019

KDS2010, a MAO-B inhibitor, shows a long-lasting effect in alleviating memory impairment in an Alzheimer’s disease mouse model.
Zooming in on protons: Neutron structure of protein kinase A trapped in a product complex
Authors: Gerlits Oksana , Weiss Kevin L. , Blakeley Matthew P. , Veglia Gianluigi , Taylor Susan S. , Kovalevsky Andrey
Published: March 2019

Neutrons reveal previously unknown protonation states of amino acid residues in protein kinase A—a prototype for the kinase family.
pH-dependent gating mechanism of the
Helicobacter pylori
urea channel revealed by cryo-EM
Authors: Cui Yanxiang , Zhou Kang , Strugatsky David , Wen Yi , Sachs George , Zhou Z. Hong , Munson Keith
Published: March 2019

Comparison of closed and open channels defines pH-dependent gating mechanism and cooperativity between protomers in the hexamer.
Amphiphysin 2 modulation rescues myotubular myopathy and prevents focal adhesion defects in mice
Authors: Lionello Valentina M. , Nicot Anne-Sophie , Sartori Maxime , Kretz Christine , Kessler Pascal , Buono Suzie , Djerroud Sarah , Messaddeq Nadia , Koebel Pascale , Prokic Ivana , Hérault Yann , Romero Norma B. , Laporte Jocelyn , Cowling Belinda S.
Published: March 2019

Modulation of human amphiphysin 2 expression by genetic cross and viral delivery rescues all hallmarks of X-linked centronuclear myopathy in mice.
Low Antituberculosis Drug Concentrations in HIV-Tuberculosis-Coinfected Adults with Low Body Weight: Is It Time To Update Dosing Guidelines?
Authors: Sekaggya-Wiltshire Christine , Chirehwa Maxwell , Musaazi Joseph , von Braun Amrei , Buzibye Allan , Muller Daniel , Gutteck Ursula , Motta Ilaria , Calcagno Andrea , Fehr Jan S. , Kambugu Andrew , Castelnuovo Barbara , Lamorde Mohammed , Denti Paolo
Published: March 2019

Antituberculosis drugs display large pharmacokinetic variability, which may be influenced by several factors, including body size, genetic differences, and drug-drug interactions. We set out to determine these factors, quantify their effect, and determine the dose adjustments necessary for optimal drug concentrations.
Draft Genome Sequences of 10 Paenibacillus and Bacillus sp. Strains Isolated from Healthy Tomato Plants and Rhizosphere Soil
Authors: Zhou Lu , Song Chunxu , de Jong Anne , Kuipers Oscar P.
Published: March 2019

In order to investigate the underlying interaction mechanisms between plants and Gram-positive bacteria, 10
Paenibacillus
and
Bacillus
strains were isolated from healthy tomato rhizosphere and plant tissues.
Transcriptome Sequence of Antibiotic-Treated Pseudomonas aeruginosa
Authors: Esani Saika , Chen Tsute , Leung Kai P. , Van Laar Tricia A.
Published: March 2019

Pseudomonas aeruginosa
is known to tolerate antibiotic therapy during infection. This prevents clearance of infection and negatively impacts patient outcomes.
Complete Genome Sequence of Lactobacillus crispatus AB70, Isolated from a Vaginal Swab from a Healthy Pregnant Korean Woman
Authors: Chang Dong-Ho , Rhee Moon-Soo , Lee Sung-Ki , Chung In-Hwa , Jeong Haeyoung , Kim Byoung-Chan
Published: March 2019

The vaginal bacterial strain AB70, belonging to the species
Lactobacillus crispatus
, was isolated from a vaginal swab from a healthy pregnant Korean woman. Here, we report the 2.37-Mb complete genome sequence of this strain.
Pharmacy services at the PyeongChang 2018 Olympic and Paralympic Winter Games
Authors: Stuart Mark , Kwon Young In , Rhie Sandy Jeong
Published: March 2019

Objective

Pharmacy services at large multisport events support safe and effective medication use. Our aim is to describe the contribution of pharmacists and to share the pharmacy experiences at the 2018 PyeongChang Olympic and Paralympic Games.

Methods

The data collected included the accreditation details of patients and prescribers indicating: sport, country, athlete or non-athlete status, and prescription details including: medication, strength, frequency, length of treatment, for the period of the Olympic Games (1–26 February 2018) and the Paralympic Games (5–20 March 2018). The numbers of prescriptions dispensed were analysed by medication category, sports and country of the patient.

Results

A total of 5313 medication items were dispensed over the course of the Olympic and Paralympic Games (athletes: 670; non-athletes: 4615; unknown: 28), for a total of 2360 patients. 72 of 82 countries (87.8%) had fewer than 20 patient visits. The first high peak (Olympic: 5.0%; Paralympic: 7.3%) of daily volume of prescriptions were dispensed in the 2 days prior to the Olympic and the 1 day prior to Paralympic opening ceremonies. Therapeutic Use Exemption (TUE) and International Olympic Committee NeedlePolicy were well managed and compliant with the regulations.

Conclusion

Pharmacy services at major multisport games include dispensing over 5000 prescriptions, supporting the TUE and IOC Needle Policy processes and providing clinical information to athletes and prescribers on drugs in sports and the World Anti-Doping Agency regulations of drugs prohibited in sport. During the PyeongChang 2018 Olympic and Paralympic Winter Games, pharmacists played a crucial role in delivering safe and effective pharmacy service based on their expert knowledge in antidoping and the clinical use of drugs in sport.
Long-standing groin pain in contact sports: a prospective case–control and MRI study
Authors: Paajanen Hannu , Hermunen Heikki , Ristolainen Leena , Branci Sonia
Published: March 2019

Objectives

We aimed to prospectively evaluate the prevalence of long-standing groin pain and related MRI findings in contact sports.

Methods

This case–control study followed three male elite-level soccer, ice-hockey and bandy teams (102 players) for 2 years. All athletes with long-standing groin pain lasting >30 days and age-matched controls (1:3) from the same teams were examined clinically, using pelvic MRI and Hip and Groin Outcome Scores (HAGOS). Primary outcome measures were annual prevalence of groin pain and underlying MRI findings.

Results

The annual prevalence of chronic groin pain was 7.5%. Training characteristics and pain scores of athletes were similar in all teams. On MRI, there was no significant difference in the percentage of pubic bone marrow oedema (p = 0.80) between symptomatic players (8/15; 53%) versus controls (20/43; 47%), but adductor tendinopathy and degenerative changes at the pubic symphysis were twice more common among players with pain. Rectus muscle or iliopsoas pathology were seldom observed. Lower HAGOS subscales (p < 0.01) were recorded in players who experienced groin pain compared with the controls.

Conclusion

Long-standing groin pain was observed annually in 1 of 14 athletes in contact sports. Abnormalities in the pubic symphysis were common MRI findings in both symptomatic and asymptomatic players.

Trial registration number

NCT02560480
Influence of type and duration of training on the presence of an abnormal ECG in high-performance athletes
Authors: Verrall Geoffrey , Hains Angus , Ayres Bronte , Hillock Richard
Published: March 2019

Objective

To undertake an ECG in high level athletes to determine the morphology of the ECG and to assess the influences on the ECG of the amount of time in a high-performance programme and the type of sport played.

Design

Cross-sectional cohort study.

Setting

High-performance sports programme.

Interventions

Current symptoms (questionnaire) and length of time in a high-performance sports programme were recorded. Sports were classified as either high maximal oxygen uptake continuous, high maximal oxygen uptake repeated effort or static. An ECG was performed and classified by 2010 European Society of Cardiology guidelines into Groups 0 (normal), Group 1 (common and training-related ECG changes) and Group 2 (uncommon and training unrelated ECG changes).

Results

The following were recorded: length of time in high performance sport programme (mean 2.3 years), type of sport (Continuous 103, Repeated effort 133, Static 37), ECG changes Group 0 (n=83, 31%), Group 1 (n=173, 63%) and Group 2 (n=17, 6.2%). Athletes with an increased length of time in a high performance programme demonstrated a higher likelihood of Group 2 ECG changes when compared with Groups 0 and 1 (p=0.05). The questionnaire did not help detect athletes with Group 2 ECG changes.

Conclusions

This study demonstrates that an increased length of time in a high performance programme was associated with an increased number of detectable Group 2 ECG changes. Overall, the further investigation rate was 6.2%.
Genetic linkage analysis of a large family identifies FIGN as a candidate modulator of reduced penetrance in heritable pulmonary arterial hypertension
Authors: Puigdevall Pau , Piccari Lucilla , Blanco Isabel , Barberà Joan Albert , Geiger Dan , Badenas Celia , Milà Montserrat , Castelo Robert , Madrigal Irene
Published: March 2019

Background

Mapping the genetic component of molecular mechanisms responsible for the reduced penetrance (RP) of rare disorders constitutes one of the most challenging problems in human genetics. Heritable pulmonary arterial hypertension (PAH) is one such disorder characterised by rare mutations mostly occurring in the bone morphogenetic protein receptor type 2 (BMPR2) gene and a wide heterogeneity of penetrance modifier mechanisms. Here, we analyse 32 genotyped individuals from a large Iberian family of 65 members, including 22 carriers of the pathogenic BMPR2 mutation c.1472G>A (p.Arg491Gln), 8 of them diagnosed with PAH by right-heart catheterisation, leading to an RP rate of 36.4%.

Methods

We performed a linkage analysis on the genotyping data to search for genetic modifiers of penetrance. Using functional genomics data, we characterised the candidate region identified by linkage analysis. We also predicted the haplotype segregation within the family.

Results

We identified a candidate chromosome region in 2q24.3, 38 Mb upstream from BMPR2, with significant linkage (LOD=4.09) under a PAH susceptibility model. This region contains common variants associated with vascular aetiology and shows functional evidence that the putative genetic modifier is located in the upstream distal promoter of the fidgetin (FIGN) gene.

Conclusion

Our results suggest that the genetic modifier acts through FIGN transcriptional regulation, whose expression variability would contribute to modulating heritable PAH. This finding may help to advance our understanding of RP in PAH across families sharing the p.Arg491Gln pathogenic mutation in BMPR2.
Associations of screen work with neck and upper extremity symptoms: a systematic review with meta-analysis
Authors: Coenen Pieter , van der Molen Henk F , Burdorf Alex , Huysmans Maaike A , Straker Leon , Frings-Dresen Monique HW , van der Beek Allard J
Published: March 2019

Objectives

It has often been suggested that screen work (ie, work on desktop, laptop, notebook or tablet computers) is a risk factor for neck and upper extremity symptoms. However, an up-to-date overview and quantification of evidence are lacking. We aimed to systematically review the association of exposure to screen work with neck and upper extremity symptoms from prospective studies.

Methods

An electronic database search (PubMed, Embase, Cinahl and Scopus) for prospective studies on the association of exposure to screen work and musculoskeletal symptoms was conducted. Studies were synthesised regarding extracted data and risk of bias, and meta-analyses were conducted.

Results

After screening 3423 unique references, 19 articles from 12 studies (with 18 538 participants) were included for the current review, with the most recent exposure assessment reported in 2005. Studies described duration and input frequency of screen work (ie, computer, keyboard and mouse use, assessed using self-reports or software recordings) and musculoskeletal symptoms (ie, self-reported neck/shoulder and distal upper extremity symptoms and diagnosed carpal tunnel syndrome [CTS]). Although there was overall an increased occurrence of musculoskeletal symptoms with larger exposure to screen work (relative risk: 1.11 [1.03 1.19]), findings were rather inconsistent with weaker (and statistically non-significant) risks when screen work was assessed by software recording (1.05 [0.91 1.21]) compared to with self-report (1.14 [1.03 1.19]).

Conclusions

We found an increased risk of musculoskeletal symptoms with screen work. However, the evidence is heterogeneous, and it is striking that it lacks information from contemporary screen work using laptop, notebook or tablet computers.
Estimating soil-water characteristic curve from soil-freezing characteristic curve for mine waste tailings using time domain reflectometry
Authors: Schafer Haley , Beier Nicholas
Published: March 2019

The unsaturated properties of a soil are required to predict the rate of dewatering and magnitude of strength gain of a mine waste tailings deposit during desiccation dewatering. This prediction requires the soil-water characteristic curve (SWCC), which is time-consuming and challenging to attain and may take anywhere from weeks to months to complete a single test. As a result, alternative methods are needed to estimate the SWCC. Past research has indicated that the soil-freezing characteristic curve (SFCC) can be used to estimate the SWCC in some soils. An experimental method and apparatus were developed to measure the SFCC to estimate the SWCC for different mine waste tailings, including copper tailings, gold tailings, and oil sands centrifuge cake. The experimental method involved using a resistance temperature detector to measure the temperature and time domain reflectometry to determine the unfrozen water content of the soil. The results showed that the SFCC could be used to estimate the SWCC for tailings from metal mines (gold tailings and copper tailings) with a high portion of sand-sized particles and a small amount of clay-sized particles, but was not able to estimate the SWCC for oil sands tailings.
Toward universality in degree 2 of the Kricker lift of the Kontsevich integral and the Lescop equivariant invariant
Authors: Audoux Benjamin , Moussard Delphine
Published: March 2019

In the setting of finite type invariants for null-homologous knots in rational homology 3-spheres with respect to null Lagrangian-preserving surgeries, there are two candidates to be universal invariants, defined, respectively, by Kricker and Lescop. In a previous paper, the second author defined maps between spaces of Jacobi diagrams. Injectivity for these maps would imply that Kricker and Lescop invariants are indeed universal invariants; this would prove in particular that these two invariants are equivalent. In the present paper, we investigate the injectivity status of these maps for degree 2 invariants, in the case of knots whose Blanchfield modules are direct sums of isomorphic Blanchfield modules of [Formula: see text]-dimension two. We prove that they are always injective except in one case, for which we determine explicitly the kernel.
A cluster controller for transition matrix calculations
Authors: Yevick David , Lee Yong Hwan
Published: March 2019

We demonstrate that a temperature schedule for single-spin flip transition matrix calculations can be simply and rapidly generated by monitoring the average size of the Wolff clusters at a set of discrete temperatures. Optimizing this schedule yields a potentially interesting quantity related to the fractal structure of Ising clusters. We also introduce a technique in which the transition matrix is constructed at a sequence of discrete temperatures at which Wolff cluster reversals are alternated with certain series of single-spin flip steps. The single spin-flip transitions are then employed to construct a single transition matrix.
Accurate Detection of ECG Signals in ECG Monitoring Systems by Eliminating the Motion Artifacts and Improving the Signal Quality Using SSG Filter with DBE
Authors: Dembrani Mahesh B. , Khanchandani K. B. , Zurani Anita
Published: March 2019

The automatic recognition of QRS complexes in an Electrocardiography (ECG) signal is a critical step in any programmed ECG signal investigation, particularly when the ECG signal taken from the pregnant women additionally contains the signal of the fetus and some motion artifact signals. Separation of ECG signals of mother and fetus and investigation of the cardiac disorders of the mother are demanding tasks, since only one single device is utilized and it gets a blend of different heart beats. In order to resolve such problems we propose a design of new reconfigurable Subtractive Savitzky–Golay (SSG) filter with Digital Processor Back-end (DBE) in this paper. The separation of signals is done using Independent Component Analysis (ICA) algorithm and then the motion artifacts are removed from the extracted mother’s signal. The combinational use of SSG filter and DBE enhances the signal quality and helps in detecting the QRS complex from the ECG signal particularly the R peak accurately. The experimental results of ECG signal analysis show the importance of our proposed method.
Modeling Analysis and Diagnosis of Analog Circuits in z-Domain
Authors: Tadeusiewicz Michał , Ossowski Marek
Published: March 2019

The paper is dedicated to the linear time-invariant analog electronic circuits. It deals with the problem of modeling of the circuits in the [Formula: see text]-domain. The model put forward in this paper enables solving different issues with the analysis of linear dynamic circuits. The model’s usefulness to fault diagnosis is emphasized in the paper, especially its application to multiple soft fault diagnosis of linear circuits. To make such diagnosis possible, the node equations with unknown node voltages and the diagnosed parameters are used. The set of actual values of the verified parameters is achieved by solving an appropriate system of algebraic nonlinear equations associated to the node equations. It can be determined using the Newton algorithm with adaptive choice of damping parameter. The diagnosis method is adjusted to real conditions by considering the deviations of the healthy parameters inside their tolerance scopes. Two real-life electronic circuits are considered to illustrate the method.
Design of a Variable Sampling Interval EWMA Median Control Chart
Authors: Tran Kim Phuc , Castagliola Philippe , Nguyen Thi Hien , Cuzol Anne
Published: March 2019

In the literature, median type control charts have been widely investigated as easy and efficient means to monitor the process mean when observations are from a normal distribution. In this work, a Variable Sampling Interval (VSI) Exponentially Weighted Moving Average (EWMA) median control chart is proposed and studied. The Markov chains are used to calculate the average run length to signal (ARL). A performance comparison with the original EWMA median control chart is made. The numerical results show that the proposed chart is considerably more effective as it is faster in detecting process shifts. Finally, the implementation of the proposed chart is illustrated with an example in food production process.
Random Age Replacement Policies with Periodic Planning Times
Authors: Mizutani Satoshi , Zhao Xufeng , Nakagawa Toshio
Published: March 2019

The random age replacement policies discussed in literatures are helpful to complete the nonstopping works with random working cycles, however, maintenance policies are more easily performed at periodic times in real applications. For such a viewpoint, this paper proposes that age replacement policies are planned at periodic times while considering the random working cycles. Using the modeling approaches of replacement first and last policies, we discuss two models such that the unit is replaced at periodic times [Formula: see text] and working cycles [Formula: see text], whichever occurs first and whichever occurs last. The expected cost rate models are obtained and their optimal solutions for [Formula: see text] and [Formula: see text] are discussed. The comparisons between the policies of [Formula: see text] and [Formula: see text], and replacement first and last are made from the point of cost. Numerical examples are illustrated when the failure time has a Weibull distribution.
Controlled weaving frames in Hilbert spaces
Authors: Rezapour Reza , Rahimi Asghar , Osgooei Elnaz , Dehghan Hossein
Published: March 2019

In this paper, we first introduce the notion of controlled weaving [Formula: see text]-[Formula: see text]-frames in Hilbert spaces. Then, we present sufficient conditions for controlled weaving [Formula: see text]-[Formula: see text]-frames in separable Hilbert spaces. Also, a characterization of controlled weaving [Formula: see text]-[Formula: see text]-frames is given in terms of an operator. Finally, we show that if bounds of frames associated with atomic spaces are positively confined, then controlled [Formula: see text]-[Formula: see text]-woven frames give ordinary weaving [Formula: see text]-frames and vice-versa.
Partial groupoid actions on R-categories: Globalization and the smash product
Authors: Marín Víctor , Pinedo Héctor
Published: March 2019

In this paper, we introduce the concept of partial groupoid actions on [Formula: see text]-semicategories as well as we give criteria for existence of a globalization of it. This point of view is a generalization of the notions of partial groupoid actions on rings and partial group action on an [Formula: see text]-semicategory. We also define the notions of partial skew groupoid category, smash product and describe functorial relations between them, in particular we show that the smash product is a Galois covering of its associated skew groupoid category.
Discovery of novel anaplastic lymphoma kinase inhibitors: Structure and energy-based pharmacophore strategy
Authors: James Nivya , Shanthi V. , Ramanathan K.
Published: March 2019

The clinical outcomes in patients with non-small cell lung cancer have improved, as a result of anaplastic lymphoma kinase (ALK) inhibition. Therefore in the current study, substantial effort has been made to identify ALK inhibitors through systematic virtual screening experiment consisting of e-pharmacophore and pharmacophore perception techniques. Initially, a pharmacophore model (AAAHP.193) and an e-pharmacophore model (DDRRR) encompassing the whole dataset of 12 known ALK inhibitors were developed. The hypotheses could retrieve effective compounds from DrugBank database (8621 molecules), which were then subjected to molecular docking and ADME prediction. These approaches resulted in the identification of five hits, namely, nebivolol, HDY, D42, 796, and LZE having higher Glide docking scores and promising ADME properties with augmented CNS involvement. Moreover, molecular dynamics simulations were performed to validate the inhibitory activity of the hit compounds, and density functional theory calculations were carried out to scrutinize the chemical reactivity of the hits. Subsequent interaction and scaffold analysis identified prominent interactions of the hits with ALK kinase domain and scaffolds with anti-tumor activity against lung cancer cell lines. We strongly believe that the study provides an outlook for the sighting of novel and potent ALK inhibitors in the near future.
Information geometric complexity of entropic motion on curved statistical manifolds under different metrizations of probability spaces
Authors: Gassner Steven , Cafaro Carlo
Published: March 2019

We investigate the effect of different metrizations of probability spaces on the information geometric complexity of entropic motion on curved statistical manifolds. Specifically, we provide a comparative analysis based upon Riemannian geometric properties and entropic dynamical features of a Gaussian probability space where the two distinct dissimilarity measures between probability distributions are the Fisher–Rao information metric and the [Formula: see text]-order entropy metric. In the former case, we observe an asymptotic linear temporal growth of the information geometric entropy (IGE) together with a fast convergence to the final state of the system. In the latter case, instead, we note an asymptotic logarithmic temporal growth of the IGE together with a slow convergence to the final state of the system. Finally, motivated by our findings, we provide some insights on a tradeoff between complexity and speed of convergence to the final state in our information geometric approach to problems of entropic inference.
Scanning photoacoustic imaging of submucosal gastric tumor based on a long focused transducer in phantom and in vitro experiments
Authors: Wu Hua-Qin , Wang Hao-Yu , Xie Wen-Ming , Wu Shu-Lian , Li Zhi-Fang , Zhang Xiao-Man , Li Hui
Published: March 2019

Photoacoustic imaging, which can provide the maximum intensity contrast in tissue depth imaging without ionizing radiation, will be a promising imaging trend for tumor detection. In this paper, a column diffusion fiber was employed to carry a pulsed laser for irradiating stomach directly through esophagus based on the characteristics of gastric tissue structure. A long focused ultrasonic transducer was placed outside the body to detect photoacoustic signals of gastric tissue. Phantom and in vitro experiments of submucosal gastric tumors were carried out to check the sensitivity of scanning photoacoustic tomography system, including the lateral and longitudinal resolution of the system, sensitivity of different absorption coefficient in imaging, capability of transversal detection, and probability of longitudinal detection. The results demonstrate that our innovative technique can improve the parameters of imaging. The lateral resolution reaches 2.09[Formula: see text]mm. Then a depth of 5.5[Formula: see text]mm with a longitudinal accuracy of 0.36[Formula: see text]mm below gastric mucosa of early gastric cancer (EGC) has been achieved. In addition, the optimal absorption coefficient differences among absorbers of system are 3.3–3.9 times. Results indicate that our photoacoustic imaging (PAI) system, is based on a long focusing transducer, can provide a potential application for detecting submucosal EGC without obvious symptoms.
Multiple-criteria fuzzy group decision-making with multi-choice goal programming for supplier selection: A case study
Authors: Bera Ashoke Kumar , Jana Dipak Kumar , Banerjee Debamalya , Nandy Titas
Published: March 2019

In today’s highly turbulent and competitive environment, the success of the organization depends on the performance of its suppliers. However, supplier selection problems are complex as they involve a large number of criteria and, frequently, some of the criteria cannot be evaluated precisely. Moreover, fluctuations of supplier performances and unknown information always exist in real-world decision-making. It is a complex multiple-criteria decision-making (MCDM) problem as it involves a trade-off among various criteria with vagueness and imprecision and also involves a group of experts with diverse opinion. Therefore, to make more practical decisions, this paper is intended to propose an integrated technique for order preference by similarity to ideal solution (TOPSIS) in fuzzy environment with multi-choice goal programming (MCGP) to handle the supplier assessment and order allocation for a battery manufacturing organization. Using linguistic variables, the decision-makers assess the rating of suppliers as well as the importance of various factors. Linguistic variables are expressed in trapezoidal fuzzy numbers (TrFN). Fuzzy-TOPSIS method is proposed to obtain the rank of suppliers and MCGP method is used to allocate suitable orders to the selected suppliers. A case study is implemented to find the applicability and validity of the proposed model. Finally, sensitivity analysis is performed to observe the effect of weights of criteria on supplier evaluation problem.
Conformance testing of FMI calling sequence for simulation environments
Authors: Mukbil Awad , Durak Umut , Hartmann Sven
Published: March 2019

Exchanging simulation models is currently of utmost importance. To improve interoperability between suppliers and original equipment manufacturers (OEMs), the functional mock-up interface (FMI) is exchanged in a standard format called functional mock-up unit (FMU). Since its first release, many simulation tools took the initiative to support FMI. However, since then, there have been many complaints stating that exchanging models via FMI does not work as stable as expected. The reason usually turned out to be the implementation of tool vendors that sometimes fail to comply with the standard fully. This paper introduces a methodology for testing FMI compliance of importing simulation tools using a set of reference FMUs. The standard defines the implementation of FMI functions calling sequence in a state machine. Therefore, conformance testing (also called fault detection) from automata theory is utilized to produce reference FMUs based on the FMI state-machine.
All Perpendicular Spin Nano-Oscillators with Composite Free Layer
Authors: Wei Jiaqi , Cao Kaihua , Cui Hushan , Shi Kewen , Cai Wenlong , Li Huisong , Jing Yang , Zhao Chao , Zhao Weisheng
Published: March 2019

Owing to improved thermal stability and scalability, materials with perpendicular magnetic anisotropy (PMA) are extremely attractive. The all perpendicular magnetic tunnel junction ([Formula: see text]-MTJ) devices are primarily devoted to spin transfer torque (STT)-induced switching and few works report their microwave emission. Here, we demonstrate the basic results of RF function in nanoscale [Formula: see text]-MTJ which has two different thickness free layers separated by atom-thick tungsten insertion. The ultrathin W spacer layer not only enables the two CoFeB free layers precess as a single layer but also greatly enhances the PMA which further induces high-emission frequency. The all perpendicular spin transfer torque nano-oscillator (STNO) exhibited high frequency (7.6[Formula: see text]GHz) and large current modulation capability of [Formula: see text] at moderate external magnetic field. Along with our previous work on STT switching utilizing the similar stack, such a multifunctional structure could bring low cost solutions to Internet of Things (IoT) network applications.
Spin-Based Fully Nonvolatile Full-Adder Circuit for Computing in Memory
Authors: Amirany Abdolah , Rajaei Ramin
Published: March 2019

As CMOS technology scales down toward below 2-digit nanometer dimensions, exponentially increasing leakage power, vulnerability to radiation induced soft errors have become a major problem in today’s logic circuits. Emerging spin-based logic circuits and architectures based on nonvolatile magnetic tunnel junction (MTJ) cells show a great potential to overcome the aforementioned issues. However, radiation induced soft errors are still a problem in MTJ-based circuits as they need sequential peripheral CMOS circuits for sensing the MTJs. This paper proposes a novel nonvolatile and low-cost radiation hardened magnetic full adder (MFA). In comparison with the previous designs, the proposed MFA is capable of tolerating particle strikes regardless of the amount of charge induced to a single node and even multiple nodes. Besides, the proposed MFA offers low power operation, low area and high performance as compared with previous counterparts. One of the most important features suggested by the proposed MFA circuit is full nonvolatility. Nonvolatile logic circuits remove the cost of high volume data transactions between memory and logic and also facilitate power gating in logic-in-memory architectures.
Raman Imaging of Small Biomolecules
Authors: Shen Yihui , Hu Fanghao , Min Wei
Published: March 2019

Imaging techniques greatly facilitate the comprehensive knowledge of biological systems. Although imaging methodology for biomacromolecules such as protein and nucleic acids has been long established, microscopic techniques and contrast mechanisms are relatively limited for small biomolecules, which are equally important participants in biological processes. Recent developments in Raman imaging, including both microscopy and tailored vibrational tags, have created exciting opportunities for noninvasive imaging of small biomolecules in living cells, tissues, and organisms. Here, we summarize the principle and workflow of small-biomolecule imaging by Raman microscopy. Then, we review recent efforts in imaging, for example, lipids, metabolites, and drugs. The unique advantage of Raman imaging has been manifested in a variety of applications that have provided novel biological insights.
Multireference Theories of Electron Correlation Based on the Driven Similarity Renormalization Group
Authors: Li Chenyang , Evangelista Francesco A.
Published: March 2019

The driven similarity renormalization group (DSRG) provides an alternative way to address the intruder state problem in quantum chemistry. In this review, we discuss recent developments of multireference methods based on the DSRG. We provide a pedagogical introduction to the DSRG and its various extensions and discuss its formal properties in great detail. In addition, we report several illustrative applications of the DSRG to molecular systems.
Identification of transmembrane protein 237 as a novel interactor with the intestinal riboflavin transporter-3 (RFVT-3): role in functionality and cell biology
Authors: Sabui Subrata , Subramanian Veedamali S. , Pham Quang , Said Hamid M.
Published: March 2019

The apically localized riboflavin (RF) transporter-3 (RFVT-3) is involved in intestinal absorption of vitamin B2. Previous studies have characterized different physiological/biological aspects of the RFVT-3, but there is a lack of knowledge regarding possible existence of interacting partner(s) and consequence of interaction(s) on its function/cell biology. To address the latter, we performed yeast two-hybrid (Y2H) screening of a human colonic cDNA library and have identified transmembrane protein 237 (TMEM237) as a putative interactor with the human (h)RFVT-3; the interaction was further confirmed via “1-by-1” Y2H assay that involved appropriate positive and negative controls. TMEM237 was found to be highly expressed in human native intestine and in human intestinal epithelial cell lines; further, confocal images showed colocalization of the protein with hRFVT-3. The interaction between TMEM237 with hRFVT-3 in human intestinal epithelial HuTu-80 cells was established by coimmunoprecipitation. Expressing TMEM237 in HuTu-80 cells led to a significant induction in RF uptake, while its knockdown (with the use of gene-specific siRNA) led to a significant reduction in uptake. Transfecting TMEM237 into HuTu-80 cells also led to a marked enhancement in hRFVT-3 protein stability (reflected by an increase in the protein half-life). Interestingly, the level of expression of TMEM237 was found to be markedly reduced following treatment with TNF-α (a proinflammatory cytokine that inhibits intestinal RF uptake), while its expression was significantly upregulated following treatment with butyrate (an inducer of intestinal RF uptake). These findings identify TMEM237 as an interactor with the intestinal hRFVT-3 and show that the interaction has physiological/biological significance.