bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Analysis of Mathematical Models for Turbofan Engine Weight Estimation
Authors: Kuz’michev Venedikt , Krupenich Ilia , Filinov Evgeny , Ostapyuk Yaroslav
Published: October 2018

Accurate mathematical models for turbofan engine weight estimation are necessary requirement for optimization of the working process parameters at the initial design stage. Open-access publications provide necessary information on eight models that may be used at this design stage. Information on 77 modern turbofan engines was gathered using the available sources: publications, official websites, reference books etc. Data gaps were filled using the mathematical model identification. Gathered data cover wide range of working process parameters, thrust levels and air flow rates and was used to assess the accuracy of the abovementioned weight models. Only four models (Torenbeek, Svoboda, Raymer, Kuz’michev) provide adequate accuracy. Kuz’michev model uses the highest number of input parameters and provide the most precise results, although it must be noted that no correlation between the number of input parameters and accuracy was determined in general.
Analytical and Experimental Studies of Rapid Cloth Drying for Technological Innovation
Authors: Chailoet Atcharaporn , Kliniam Tanapon , Muangpisan Ranet , Kiatkungwankai Peerawich , Leephakpreeda Thananchai
Published: October 2018

This paper presents analytical and experimental studies of a rapid cloth drying process. The mathematical models are developed from mass diffusion of wet clothes under hot and dry air conditions There are three critical factors: air temperature, air humidity, and the mass transport coefficient. Experiments of outdoor cloth drying are investigated as a benchmark. It is found drying duration is about 2-3 hours for satisfactory drying states under sunny weather. To reduce drying period, the mass transport coefficient is the highest sensitive factor while it can be adjusted by air speed through clothes. Experimental results of a rapid cloth drying heat pump show that the drying period can be reduced to 12 minutes with COP of 5.4. This understanding is able to strengthen development of rapid cloth drying for technological innovation.
Micro Electromagnetic Actuator - Static Behavior
Authors: Comeaga Constantin Daniel , Ovezea Dragos , Ilie Cristinel
Published: October 2018

The article presents a comparative study regarding the design and experimental results for a miniature electromagnetic actuator with a modified design comparing with the classical type, including a mobile array of micro-magnets and a fixed coil in two configurations (planar spiral multi-layered and cylindrical). Previous work on design, modeling and simulation of this type of actuator indicated the optimum design and conducted to dimensions and material parameters. Different types of actuators were produced and experimentally tested, showing good results but also some drawbacks. Three of these design solutions are presented together with the static voltage-deflection and electrical impedances curves, experimentally derived. The results confirmed the feasibility of two actuating solution, showing good linearity and possibility to control the position at h accuracy and indicated improving directions.
Trajectory Planning of a 6D Robot based on Meta Heuristic Algorithms
Authors: Wichapong Kritsada , Pholdee Nantiwat , Bureerat Sujin , Radpukdee Thana
Published: October 2018

In this work, several established meta-heuristics (MHs) were employed for solving 6-DOF robot trajectory planning. A fourth order polynomial function is used to represent a motion path of the robot from initial to final points while an optimisation problem is posed to minimise travelling time subject to velocity, acceleration and jerk constraints. The design variables are joint velocities and accelerations at intermediate positions, and moving time from the initial position to the intermediate position and from the intermediate position to the final position. Several MHs are used to solve the trajectory optimisation problem of robot manipulators while their performances are investigated. Based on this study, the best MH for robot trajectory planning is found while the results obtained from such a method are set as the baseline for further study of robot trajectory planning optimisation.
Research on Convolutional Neural Network Model for Sonar IMAGE Segmentation
Authors: Jiao Shengxi , Zhao Chunyu , Xin Ye
Published: October 2018

The speckle noise of sonar images affects the human interpretation and automatic recognition of images seriously. It is important and difficult to realize the precision segmentation of sonar image with speckle noise in the field of image processing. Full convolution neural network (FCN) has the advantage of accepting arbitrary size image and preserving spatial information of original input image. In this paper, the image features are obtained by autonomic learning of convolutional neural network, the original learning rules based on the mean square error loss function is improved. Taking the pixel as the processing unit, the segmentation method based on FCN model with relative loss function(FCN-RLF) for small submarine sonar image is proposed, sonar image pixel-level segmentation is achievied. Experimental results show that the improved algorithm can improve the segmentation accuracy and keep the edge and detail of sonar image better. The proposed model has better ability to reject sonar image speckle noise.
Design for Supplier Performance Assessment Model of Information Technology Service Provider in Small Medium Enterprises in Indonesia
Authors: Kusrini Elisa , Usman Alfanugrah Hi
Published: October 2018

This study aims to design a supplier performance assessment model for information technology services provider in small medium enterprises (SME) in Indonesia. Supplier performance assessment is important to improve supplier performance and maintain long-term relationships between SME (buyer) and their suppliers. This supplier Assessment models are developed based on the review literature and interviews with procurement staff in SMEs. Performance assessment criteria are identified and tested for validity by providing a questionnaire to procurement section in SMEs. In order to obtain importance weight of each criteria toward performance score, a questionnaire to weighed the criteria are distributed to procurement staff and analyzed the answers using the Analytical Hierarchy Process (AHP) method. The final performance score is calculated based on the standardized value of each criteria multiplied by its weight. Based on the implementation of this model in SMEs, it is known that the proposed model is suitable to assess the supplier’s performance and greatly help the SMEs in managing the performance of their suppliers.
Non-linear Analysis of Vibrating Flip-flow Screens
Authors: Gong Sanpeng , Wang Xinwen , Oberst Sebastian
Published: October 2018

Vibrating flip-flow screens provide an effective solution for the screening of highly viscous or fine materials. Apart from other factors, the vibration characteristics of the main and floating screen frames are largely responsible for the flip-flow screen’s sifting performance and its processing capacity. In this paper, the vibration characteristics of a vibrating flip-flow screen with linear and nonlinear springs are compared. Analytical results highlight that increasing the relative amplitude and avoiding undesirable resonances of the main and the floating screen frames can be realised to improve the screen’s performance. The materials on the screen panel have less an effect on the vibration characteristics of the vibrating flip-flow screen with nonlinear springs than using linear springs. Other design parameters which influence the performance of vibrating flip-flow screens are discussed.
Characteristic of materials for the 3D printed building constructions by additive printing
Authors: Pacewicz Katarzyna , Sobotka Anna , Gołek Łukasz
Published: October 2018

Three dimensional printing is a promising new technology to erect construction objects. Around the world in every moment a new prototypes constructions are made by using this method. Three dimensional printing is taken into account as technology which can be used to print constructions in automated way on the Moon or Mars. The raw materials, which can be used with three dimensional printing have to fulfil basic requirements for those which are used in construction. That means that components of printing mortars are made from ingredients easily accessible in area nearby construction site and can be reusable. The cost of printing building objects due to that requirements is comparable to costs of traditional building, which are currently available. However additive techniques of printing needs a dedicated mortars for printer supplying. Characteristic for such mortars is: setting time, compressive strength, followability in the printing system, shape stability of every printed layer, controlling the hydration rate to ensure bonding with the subsequent layer, reusable capabilities, easily accessible raw materials, cost of such mixtures shouldn’t be too high in order to keep 3D printing competitive for traditional ways of building, mortar components should be recyclable and printing process should not influence negatively on an environment and people. All properties of printing mortars are determined by the device for additive application method. In this paper review of available materials used for three dimensional printing technology at construction site is presented. Presented materials were analysed in terms of requirements for building materials technology. Due to the lack of detailed information’s in available literature, regarding to the properties of raw materials, the results of this analysis may be used in the designing of new concrete mixtures for the use in three-dimensional printing technology for construction.
Application of Axiomatic Design for Agile Product Development
Authors: Puik Erik , Ceglarek Dareks
Published: October 2018

Agile, and iterative, development methods for new product development are gaining in popularity under product engineers; where it initially was just applied for software development, now larger adoption takes place for product development in general. The design rules of agile development are somewhat conflicting with the guidelines of Axiomatic Design. In this paper, it is investigated why this is the case, what can be done about it, and how can the strengths of agile development be combined with Axiomatic Design to optimise methods for product design. It is shown that the methods are indeed advising on different and conflicting strategies, however, by attenuating the agile design rules in the early stage of design, and doing the same for AD in the later stage of design, best of both worlds can be combined.
The Complexity of Mapping Customer Needs... (and the Myth of a Unanimous Customer)
Authors: Vossebeld Danielle M. , Foley Joseph T. , Puik Erik
Published: October 2018

Axiomatic Design and Complexity Theory as described by Suh focus heavily on the coupling often found in functional requirements. This is so fundamental to the analysis of the design that it is the core of the Axiom of Independence which examines the coupling between functional requirements due to chosen design parameters. That said, the mapping between customer needs and functional requirements is often overlooked. In this paper we consider coupling, found due to this mapping, as a possible source of complexity in terms of a user interface to a designed product. We also re-examine the methodology of how customer needs are generated and translated into the other domains to understand how they can give further insight into the customer mindset. Based on this analysis, we believe customer domain complexity should always be examined in design that includes end-user interaction.
Reengineering of the ore preparation production process in the context of “Almalyk MMC” JSC
Authors: Naumova Margarita , Basyrov Ilnur , Aliev Khakim
Published: October 2018

The review of ore crushing and grinding processes at the mining-and-processing enterprise is presented. An alternative to the standard technology of crushing ore in cone crushers is proposed after a comparative analysis of ore grinding processes.
Impact of metal removal features in the reverse zones on shaping of the machined surface in the process of cylindrical grinding with traverse feed
Authors: Pereverzev Pavel , Akintseva Aleksandra , Alsigar Masar
Published: October 2018

This paper presents a model of the formation process of surface zones of external cylindrical grinding with traverse feed at a computer numerical control machine (CNC). This article, have investigated modelling features of the grinding process in reverse zones. On the basis of the model of grinding surface formation a detailed step by step calculations of the current values of the actual radial feed and radius dimension in different areas of a treated surface is presented. The model allows maintaining calculations with presence of the initial radial runout of the workpiece for estimated automatic cycle of radial and axial feeds changing and other technological parameters.
Approaches to nonlinear theory creation for machine tools geometric accuracy
Authors: Anikeeva Olesya , Ivakhnenko Alexander , Erenkov Oleg
Published: October 2018

The justification of the nonlinear theory creation in machines geometrical accuracy field is given in the work. The problems accountings of which don’t allow providing the consecutive linearization method adequacy at geometrical accuracy calculating of metal-cutting machines are considered. The potential sources of not linearities at calculating of metal-cutting systems accuracy and the sources of the nonlinear members appearance are revealed. At the same time the nonlinear members are considering the machines geometrical errors at a shaping function variation. The full variation of shaping function is defined and the accuracy nonlinear model of the lathe is constructed on the function basis. The directions of further researches in the field of the machines geometrical accuracy nonlinear theory are presented.
Determination of maximum working capacity of retrofittable cutters on the basis of physical-mechanical features of tool hard alloys
Authors: Artamonov Evgeniy V. , Tveryakov Andrey M. , Shtin Anton S.
Published: October 2018

This research is dedicated to the determination of maximum working capacity temperature of tool hard alloy cutters during a processing of parts by means of cutting made of hard-to-cut materials including assessment of possibility of using of tools made in Russian Federation without loss of the processing efficiency.
Formation of the surface roughness during grinding with flap wheels after shot peening
Authors: Starodubtseva Darya , Le Tri Vinh , Koltsov Vladimir
Published: October 2018

Shot peening is widely used in forming long panels and sheaths. Due to impact by shot on the processed surface, a specific microgeometry is formed, the characteristic feature of this microgeometry are the numerous dimples as the traces of shot impact with different diameters and depths. A presence of these dimples causes deterioration of the surface roughness parameters. Therefore, after shot peening the mandatory requirement is the implementation of surface grinding with flap wheels for partial removal of the dimples. The size of the assigned allowance for grinding depends on the quality requirements of the part surface. At the same time, the depths of the remaining dimples are determined by the part surface roughness requirements. After grinding, the new surface microgeometry is formed, as a combination of micro-roughness from previous types of processing and the remained dimples in result of shot peening. In this work the microgeometry formation of surface layer of the samples after shot peen forming and subsequent grinding with flap wheels was analysed. The parameters of surface roughness were measured by the method of three-dimensional optical scanning. In the measurement result, the mathematical model of the surface micro-profile formation was formulated, the analytical dependences of the position of the center plane and the arithmetic mean deviation of profile were obtained.
Comparing the efficiency of flowsheets for hot die forging on crank presses
Authors: Telegin Igor , Shumilova Tatyana
Published: October 2018

The process of manufacturing a part as a semi-finished product (a forging) using hot die forging with further machining can be performed on various types of press forging equipment following several flowsheet variants. The task of selecting the best (most effective) variant is not always obvious. The paper considers the methods of the comparative estimation of the efficiency of several variants of manufacturing a forging of the same part on the basis of the following groups of indicators: metal consumption and forging force.
Investigation of parts assembly error, taking into account the deviation of the shape of their surfaces
Authors: Bolotov Mikhail , Grachev Iliya , Kudashov Evgeny
Published: October 2018

In this article, we study the errors in the assembly of parts, taking into account the deviation of the shape of their surfaces. The developed computer model of the assembly of the engine low-pressure turbine rotor is designed to predict the values of the assembly parameters, such as radial and face run-out. The forecasting of the above assembly parameters is carried out based on the data of actual dimensions and shape of the surfaces of parts assembled as an assembly unit. The analysis of study results made it possible to obtain a conclusion about the qualitative influence of geometrical errors of the assembled parts on the error of the assembly parameters.
The nature of the change of the surface temperature of the workpiece during hot rolling of pipe steel
Authors: Nekit Vladimir , Platov Sergey , Krasnov Maksim
Published: October 2018

The article is devoted the experimental studies of deformation and temperature parameters of rolling the pipe steel on the rolling mill 5000 PJSC “MMK”. Knowledge of the regularities of the change in the surface temperature of work piece during hot rolling under the conditions of thermo mechanical deformation processes is of great theoretical and practical importance. The temperature conditions determine the energy and force parameters of rolling, as well as the mechanical properties and microstructure of the finished products. The experimental rolling was carried out in two stages: roughing at 6 passes at a temperature of 1050-900 ° C and finishing at 18-20 passes at a temperature below the start of the phase transformation of 900 ° C. The finishing rolling has been carried out in a two-phase region at the stage of polymorphic transformation in the steel. Significant differences in the nature of temperature changes at different stages of rolling are revealed.
Experimental method of calculation to estimate the thickness of lubricating film in the friction unit depending on oil absorption of contacting surfaces
Authors: Terentyev Dmitriy , Ogarkov Nikolay , Platov Sergey
Published: October 2018

The article presents the investigation of the thickness of lubricating film between contacting surfaces in heavy loaded friction units, taking into account oil absorption of rough layers. Oil absorption index depends on the kind of mechanical treatment of the surfaces and makes it possible to determine necessary characteristics of the used lubricant at the design stage of a friction unit.
Adjustment of specialized technological equipment when machining small diameter internal threads with deforming cutting taps
Authors: Novikov Pavel
Published: October 2018

The article provides options for threading process diagnostics. For the previously proposed method of diagnostics, an algorithm for adjusting the machine, equipped with a pneumatic drive and a diagnostic module was developed. The interrelation between the technological system characteristics and the device for diagnostic signal recording was shown. As a result, it is possible to provide maximum productivity of the technological operation without the loss of processing quality.
Research of reliability and efficiency of technological processes of mechanical assembly production on the basis of the common semi-Markov model
Authors: Rapatskiy Yuri , Zamorenov Mikhail , Kopp Vadim , Obzherin Yuri , Gusev Vladimir , Lipka Victoria
Published: October 2018

In the article a common semi-Markov mathematical model is considered that allows one to investigate the productivity and reliability of various technological processes of mechanical assembly production. The proposed model allows to study, inter alia, technological processes of manufacturing parts with screw and assemblies of threaded connections. Mathematical apparatus of the research is the theory of semi-Markov processes with a common phase space, which operates with a common kind of random variables distribution functions. If the considering process in the system is a subsystem located on a higher level of hierarchy, the hierarchical model for compatibility with each other levels as output simulation parameters required distribution functions. In the proposed model, based on the decision of the Markov renewal equations depend not only on the torque characteristics, but also the distribution function of time per unit of output service according to different kinds of undervalued failures.
Wave resistance to the movement of objects along the rocket track guides
Authors: Erofeev Vladimir , Lissenkova Elena , Malkhanov Alexey
Published: October 2018

The work is devoted to the study of resistance to the motion of concentrated mechanical systems along the rocket track guides, which arises as a result of the wave character of deformation of the guides. The analysis of the dependence of the wave resistance on the speed of the load is carried out.
Detecting changes simulation of the technological objects’ information states
Authors: Skatkov Aleksandr , Bryukhovetskiy Aleksey , Moiseev Dmitriy , Litvinova Raisa
Published: October 2018

The purpose of the production processes’ states simulation has two constituents. The first is to ensure the effective operation of technological facilities. The second is to improve the quality and competitiveness of the produced products. The proposed new scientific approach aims to develop the known statistical methods in the following direction. They are to be adopted for monitoring accuracy and stability of production processes: real-time processing of large amount of current data, large volumes of a priori information used for decision-making, adjusting the parameters of the monitoring system, critical technological conditions detection. It can prevent great economic damage or even catastrophic consequences.
Influence of hard alloys CEDG modes on the size of dissolved layer
Authors: Medvedeva Olga , Arkhipov Pavel , Yanyushkin Alexander
Published: October 2018

Correctly assigned technological modes of processing define the accuracy of forming, optimum mechanical and electrochemical speed of the processed material removal, quality and durability of the cutting tool as well as provide the self-sharpening conditions for the grinding wheel. The purpose of this work is to increase the efficiency of hard alloys combined electric diamond grinding (CEDG) by establishing a dependence between the amount of material removed by mechanical cutting and the depth of the layer dissolved by electrolytic processes. Achieving the stated goal allows to solve the problem of defects occurrence on the processed surface and to minimize economic expenses for machine-building production processing. The article presents the results of mathematical calculations of the parameters influence on the size of the dissolved surface layer, as well as the current dependent removal rate for hard alloys. We determine qualitative and quantitative characteristics of the hard alloy dissolved layer dependence on the mechanical and electrical parameters of CEDG, such as the depth of grinding and anode current density, and demonstrate their analytical dependence.
Computation method of geometry die of stretch forming press
Authors: Bormotin Konstantin , Aung Win
Published: October 2018

Mathematical models and numerical methods for solving inverse problems of shell forming by means of stretching on a die have been developed. The algorithms implemented in MSC.Marc allow to calculate the required punch shape. The results of simulation of the stretching technology are presented.
The rolls calibration development and caliber drawings preparation with the computer software for the bent profiles production and straight-through pipes formation for laser welding
Authors: Savina Lyudmila , Savin Valeriy , Osadchy Valentin
Published: October 2018

A computer program has been created for selecting the profiling route, calculating the rolls for the manufacture of bent symmetrical and asymmetric profiles of virtually any real configurations with the issuance of a complete set of drawings. The algorithm of the program is based on the mathematical model of the strip profiling process, which allows geometric and energy-strength parameters calculation. To create an algorithm for designing roll calibrations to produce curved profiles, a unified description of the shape of the profile was proposed. The left and right halves of the cross section of the profile are treated as separate sets of alternating straight sections and rounds. The configuration of each of them for one and the other profile half is entered separately, starting from the middle. For each point of conjugation (the beginning and end of the section), the coordinates, the rounding radius and the rotation angle are specified (or calculated in the future). The accepted profile shape description makes it possible to compile a general algorithm for calculating the roll calibrations of virtually any profiles, and not to develop an algorithm for each profile or group of profiles.
Study of the sealing elements impact on air flow distribution in a seed vessel of seeding mechanism
Authors: Popov Anton Yu. , Muratov Denis K.
Published: October 2018

The quality of the pneumatic seeding mechanism operation is defined by a variety of factors, including aerodynamic characteristic quantities. But aerodynamics of seeding systems is poorly studied. Therefore studying of the air flow distribution in a seeding mechanism seed vessel is considered to be a current issue. Overpressure seeding mechanism with a seed vessel compulsory sealing is approved as the object of the studying. The aim of the studying is to define the impact of the sealing elements shape on the air flow distribution in a seed vessel by various seeding mechanism operating modes. The building-up of the air flow distribution model is carried out at the software environment Solidworks Flow Simulation with allowance for a seeding wheel rotation. The aerodynamic model building-up technique is given. The graphic charts of airflow velocity change in an upper part of the seed vessel are made. The designed overpressure seeding mechanism aerodynamic model is analyzed.
Gesundheitskompetenz – Health Literacy
Authors: Bitzer Eva Maria , Sørensen Kristine
Published: October 2018

Dieser Beitrag gibt eine Einführung in Definition und aktuelle theoretische/konzeptuelle Modelle der Gesundheitskompetenz sowie ihre Reichweite und Bedeutung für eine moderne gesundheitliche Versorgung. Wir beleuchten Methoden der Messung von individueller Gesundheitskompetenz – und erläutern, warum es sich lohnt, sich mit Gesundheitskompetenz zu beschäftigen. Des Weiteren stellen wir Strategien und Techniken vor, mit denen Einrichtungen der gesundheitlichen Versorgung die Gesundheitskompetenz ihrer Nutzerinnen und Nutzer angemessen berücksichtigen können und geben einen Überblick über aktuelle nationale und internationale politische Initiativen zum Thema Gesundheitskompetenz.
Teilaspekte der Anwendung auch nach jahrzehntelanger praktischer Nutzung ungeklärt
Authors: Lechner Raimund
Published: October 2018

Der ursprüngliche Lake-Louise-Score (LLS) wurde auf dem „International Hypoxia Symposium“ in Lake Louise 1991 erarbeitet und 1993 reevaluiert. Er besteht aus den 5 Symptomkomplexen Kopfschmerzen, gastrointestinale Symptome, Müdigkeit/Erschöpfung, Benommenheit/Schwindel und Schlafqualität. Jedem Symptomkomplex kann eine Ausprägung von 0 (Normalbefund/keine Probleme) bis 3 (maximale Beschwerden) zugeordnet werden. Ab einer Punktzahl von 3 sind die Kriterien für die akute Bergkrankheit (Acute Mountain Sickness, AMS) erfüllt.
Imidazole-Fused Enediynes by Selective C5–C4 Alkynylations of 4,5-Dibromoimidazoles
Authors: Bellina Fabio , Lessi Marco , Panattoni Alessandro , Guglielmero Luca , Minei Pierpaolo
Published: October 2018

An efficient synthesis of symmetrical 1,2-disubstituted 4,5-dialkynylimidazoles by Sonogashira alkynylation of the corresponding 4,5-dibromo derivatives was developed. Moreover, through a careful tuning of the palladium ligand, unsymmetrical 1,2-disusbtituted 4,5-dialkynylimidazoles were also prepared through a regioselective C5 alkynylation of 4,5-dibromoimidazoles, followed by a second alkynylation involving the 4-bromo derivatives so obtained. This interesting class of imidazole-fused enediynes is also able to give thermal Bergman cycloaromatization (BC), as proved by DSC experiments.
Protodepalladation as a Strategic Elementary Step in Catalysis
Authors: Engle Keary , O’Duill Miriam
Published: October 2018

Protodepalladation is the redox-neutral conversion of a C–Pd(II) bond into a C–H bond via reaction with a Brønsted acid. It is the microscopic reverse of Pd(II)-mediated C–H cleavage. In the context of catalytic reaction development, protodepalladation offers a means of converting organopalladium(II) intermediates into organic products without a change in oxidation state at the metal center. Hence, when integrated into catalytic cycles, it can be a uniquely enabling elementary step. The goal of this review is to provide an overview of protodepalladation, including exploration of different reaction types, discussion of literature examples, and analysis of mechanistic features. Our hope is that this review will stimulate other researchers in the field to pursue new applications of this underexploited step in catalysis.

1 Introduction

2 Mechanistic Considerations

3 Examples of Synthetically Enabling Protodepalladation Reactions

3.1 Alkenylpalladium Species

3.2 Arylpalladium Species

3.3 Palladium Enolates

3.4 Alkylpalladium Species

4 Conclusion
Comparison of Birth Outcomes by Gestational Diabetes Screening Criteria
Authors: Davis Esa , Scifres Christina , Abebe Kaleab , Costacou Tina , Comer Diane , Catalano Patrick , Simhan Hyagriv , Freiberg Matthew , Day Nancy
Published: October 2018

Objectives This study is to examine the association between different diagnostic criteria for gestational diabetes mellitus (GDM) and adverse birth outcomes.

Study Design A retrospective cohort study of 5,937 women with a singleton pregnancy was conducted, who completed GDM screening between 24 to 32 weeks gestational age. Four nonoverlapping groups of women defined as: 1) Normal: glucose challenge test (GCT) <130 mg/dL, 2) elevated GCT + normal oral glucose tolerance test (OGTT): abnormal 1 hour GCT + normal 3 hour OGTT, 3) GDM/International Association of Diabetes in Pregnancy Study Group (IADPSG): abnormal 3 hour OGTT by the IADPSG criteria, and 4) GDM/Carpenter-Coustan (CC): diagnosis per CC criteria. We used logistic regression to examine the association between GDM group classification and main outcome of macrosomia and secondary birth outcomes.

Results Prevalences were GDM/CC 4.6%, GDM/IADPSG 3.0, and 7.6% overall. GDM/IADPSG group was associated with increased macrosomia (adj OR [odd ratio] 1.87; 95% CI [confidence interval]: 1.08–3.25; p = 0.02), while GDM/CC group was associated with increased preterm birth (adj OR 1.75; 95% CI: 1.05–2.80; p = 0.03).

Conclusion Little difference in birth outcomes was found between the two criteria, GDM/CC and GDM/IADPSG. Randomized controlled trials are needed to clarify the risks and benefits of these screening paradigms before their incorporation into clinical practice.
The First Dorsal Metacarpal Artery Flap Family: A Review
Authors: Couceiro Jose , de Prado Marta , Menendez Guillermo , Manteiga Zaira
Published: October 2018

Deep soft tissue injuries around the thumb can severely hinder hand function if not treated correctly. Many different surgical options have been described for the treatment of these serious lesions, including microsurgical flaps, such as toe to hand flaps, local flaps, and distant pedicled flaps. The first dorsal metacarpal artery family of flaps belongs to this last category. These flaps can be performed in different ways, as a racquet, as an island flap, and as a bilobed flap including the second metacarpal artery, among others.

The aim of the following article is to review the basic concepts involved in the use of these flaps in reconstructive hand surgery.
Elastic-plastic analysis of the crack surface vicinity under a pair of anti-plane forces applied at an arbitrary point on the crack surface
Authors: Huang Feng , Yi Zhijian , Yang Qingguo , Ma Yinhua , He Xiaobing , Zhao Chaohua , Gu Jianyi , Li Ya
Published: October 2018

An elastic-plastic analysis of the mode III crack surface vicinity was performed in an infinitely wide elastic-perfectly plastic plate, in which a pair of anti-plane forces applied at an arbitrary point on the crack surface. The crack line analysis method was used without the traditional small-scale yield condition. The plastic zone length, the plastic zone shape, and the elastic-plastic stress field in the vicinity of the crack surface were obtained analytically. Moreover, the plastic zone lengths in the vicinity of the crack surface and crack line were compared, and it was found that under a pair of anti-plane forces applied at an arbitrary point on the crack surface, the plastic zone length in the vicinity of the crack surface reached its maximum faster than that in the vicinity of the crack line under the same conditions, which indicates the stress state near the crack surface region is more detrimental than that near the crack line region. The variation of plastic zone length with the load position was also studied, and it was shown that when the point forces were closer to the crack tip, the plastic zone length was smaller and the stress state of the crack was more disadvantageous.
Quantification of probabilistic ignition thresholds of polymer-bonded explosives with microstructure defects
Authors: Wei Yaochi , Kim Seokpum , Horie Yasuyuki , Zhou Min
Published: October 2018

Microscopic defects such as voids and cracks in an energetic material significantly influence its shock sensitivity. So far, there is a lack of systematic and quantitative study of the effects of cracks both experimentally and computationally, although significant work has been done on voids. We present an approach for quantifying the effects of intragranular and interfacial cracks in polymer-bonded explosives (PBXs) via mesoscale simulations that explicitly account for such defects. Using this approach, the ignition thresholds corresponding to any given level of ignition probability and, conversely, the ignition probability corresponding to any loading condition (i.e., ignition probability maps) are predicted for PBX 9404 containing different levels of initial grain cracking or interfacial debonding. James relations are utilized to express the predicted thresholds and ignition probabilities. It is found that defects lower the ignition thresholds and cause the material to be more sensitive. This effect of defects on shock sensitivity diminishes as the shock load intensity increases. Furthermore, the sensitivity differences are rooted in energy dissipation and the consequent hotspot development. The spatial preference in hotspot distribution is studied and quantified using a parameter called the defect preference ratio (rpref). Analyses reveal that defects play an important role in the development of hotspots and thus have a strong influence on the ignition thresholds. The findings are in qualitative agreement with reported trends in experiments.
Room temperature ferromagnetic resonance in hetero-epitaxial BTO − BFO/LSMO magnetoelectric composite
Authors: Madon Benjamin , Kang Han Byul , Kang Min Gyu , Maurya Deepam , Magill Brenden A. , Alves Marcos J. P. , Wegrowe Jean-Eric , Drouhin Henri-Jean , Priya Shashank , Khodaparast Giti A.
Published: October 2018

We synthesized epitaxial BTO-BFO heterostructure with decreased leakage and simultaneously improved the multiferroic properties. This study provides new direction for ferromagnetic resonance studies, in high quality BTO-BFO films grown on LSMO. We observed small Gilbert damping (α=0.004) and the absence of large inhomogeneous broadening, in a film with 80 nm thickness of BTO-BFO on LSMO (110). This fact offers opportunities for employing this material system for spin transfer in multifunctional materials where controlling magnetization by a flow of spin angular momentum, or spin current, is crucial toward developing nanoscale spin-based memory and devices. Magnetic insulators, such as BTO-BFO on LSMO, are potentially excellent candidates for pure spin current without the existence of charge current.
Integrated plasma facing component calorimetry for measurement of shot integrated deposited energy in the NSTX-U
Authors: Gray T. K. , Allen N. , Reinke M. L. , Smalley G. , Youchison D. L. , Ellis R. , Jaworski M. A. , Looby T. , Mardenfeld M. , Wolfe D. E.
Published: October 2018

The upgrade to the National Spherical Torus eXperiment (NSTX-U) [J. Menard et al., Nucl. Fusion 52, 083015 (2012)] increases the injected neutral beam power up to 12 MW and the plasma current up to Ip = 2 MA for plasma durations up to 5 s. The graphite plasma facing components have been re-designed to handle greater heat and energy fluxes than were seen in NSTX using a castellated design. We present the experimental testing and validation of a castellated graphite target, similar to the prototype tile design, instrumented with thermocouples at various depths in the castellation. During testing, incident heat flux is provided by a programmed electron beam system and surface temperatures are measured via infrared thermography directly viewing the target surface. It was found that the thermocouple response scaled linearly with the measured surface temperature rise regardless of thermocouple depth in the castellation. A sensitivity of 14.3 °C/kJ of deposited energy was found when treating individual castellations as a semi-infinite solid.
Consolidating multiple femtosecond lasers in coupled curved plasma capillaries
Authors: Zigler A. , Botton M. , Ferber Y. , Johansson G. , Pollak O. , Dekel E. , Filippi F. , Anania M. P. , Bisesto F. , Pompili R. , Ferrario M.
Published: October 2018

The ability to guide high-energy femtosecond scale lasers while augmenting their energy is crucial in future laser based TeV particle accelerators where the laser energy depletion is the major setback. We propose, analyze, and experimentally demonstrate consolidating multiple femtosecond pulse lasers in coupled curved capillaries. We demonstrate a proof of principle scheme of coupled curved capillaries where two femtosecond laser pulses are combined. Furthermore, we show simulations that demonstrate that high-intensity short pulse lasers can be guided within a small curvature radius capillary.
Structure factors for tunneling ionization rates of molecules: General grid-based methodology and convergence studies
Authors: Dnestryan Andrey I. , Tolstikhin Oleg I. , Madsen Lars Bojer , Jensen Frank
Published: October 2018

We present a general methodology for evaluating structure factors defining the orientation dependence of tunneling ionization rates of molecules, which is a key process in strong-field physics. The method is implemented at the Hartree-Fock level of electronic structure theory and is based on an integral-equation approach to the weak-field asymptotic theory of tunneling ionization, which expresses the structure factor in terms of an integral involving the ionizing orbital and a known analytical function. The evaluation of the required integrals is done by three-dimensional quadrature which allows calculations using conventional quantum chemistry software packages. This extends the applications of the weak-field asymptotic theory to polyatomic molecules of almost arbitrary size. The method is tested by comparison with previous results and illustrated by calculating structure factors for the two degenerate highest occupied molecular orbitals (HOMOs) of benzene and for the HOMO and HOMO-1 of naphthalene.
Tutorial: Time-domain thermoreflectance (TDTR) for thermal property characterization of bulk and thin film materials
Authors: Jiang Puqing , Qian Xin , Yang Ronggui
Published: October 2018

Measuring thermal properties of materials is not only of fundamental importance in understanding the transport processes of energy carriers (electrons and phonons in solids) but also of practical interest in developing novel materials with desired thermal properties for applications in energy conversion and storage, electronics, and photonic systems. Over the past two decades, ultrafast laser-based time-domain thermoreflectance (TDTR) has emerged and evolved as a reliable, powerful, and versatile technique to measure the thermal properties of a wide range of bulk and thin film materials and their interfaces. This tutorial discusses the basics as well as the recent advances of the TDTR technique and its applications in the thermal characterization of a variety of materials. The tutorial begins with the fundamentals of the TDTR technique, serving as a guideline for understanding the basic principles of this technique. Several variations of the TDTR technique that function similarly as the standard TDTR but with their own unique features are introduced, followed by introducing different advanced TDTR configurations that were developed to meet different measurement conditions. This tutorial closes with a summary that discusses the current limitations and proposes some directions for future development.
Measurement of the Overhauser field in a two-dimensional electron system at weak magnetic fields
Authors: Qian Xuan , Ji Yang
Published: October 2018

Optically induced polarization of electron spins has been able to generate nuclear polarization via dynamic nuclear polarization (DNP), and control of this nuclear spin polarization has extensive application potentiality in spin-based quantum information processing and quantum computation. Here, we report optically induced DNP measurements in a two-dimensional electron gas embedded in a GaAs/AlGaAs heterostructure. We are able to obtain the Overhauser field Bn and show that it is proportional to the external magnetic field Bext when the latter is weak. We also show that the proportionality coefficient k between Bn and Bext can be manipulated by varying the intensity and helicity of the pump light.
Uniaxial-deformation behavior of ice Ih as described by the TIP4P/Ice and mW water models
Authors: Santos-Flórez Pedro Antonio , Ruestes Carlos J. , de Koning Maurice
Published: October 2018

Using molecular dynamics simulations, we assess the uniaxial deformation response of ice Ih as described by two popular water models, namely, the all-atom TIP4P/Ice potential and the coarse-grained mW model. In particular, we investigate the response to both tensile and compressive uniaxial deformations along the [0001] and [01¯10] crystallographic directions for a series of different temperatures. We classify the respective failure mechanisms and assess their sensitivity to strain rate and cell size. While the TIP4P/Ice model fails by either brittle cleavage under tension at low temperatures or large-scale amorphization/melting, the mW potential behaves in a much more ductile manner, displaying numerous cases in which stress relief involves the nucleation and subsequent activity of lattice dislocations. Indeed, the fact that mW behaves in such a malleable manner even at strain rates that are substantially higher than those applied in typical experiments indicates that the mW description of ice Ih is excessively ductile. One possible contribution to this enhanced malleability is the absence of explicit protons in the mW model, disregarding the fundamental asymmetry of the hydrogen bond that plays an important role in the nucleation and motion of lattice dislocations in ice Ih.
Printing wet-on-wet: Attraction and repulsion of drops on a viscous film
Authors: Hack M. A. , Costalonga M. , Segers T. , Karpitschka S. , Wijshoff H. , Snoeijer J. H.
Published: October 2018

Wet-on-wet printing is frequently used in inkjet printing for graphical and industrial applications, where substrates can be coated with a thin liquid film prior to ink drop deposition. Two drops placed close together are expected to interact via deformations of the thin viscous film, but the nature of these capillary interactions is unknown. Here, we show that the interaction can be attractive or repulsive depending on the distance separating the two drops. The distance at which the interaction changes from attraction to repulsion is found to depend on the thickness of the film and increases over time. We reveal the origin of the non-monotonic interactions, which lies in the appearance of a visco-capillary wave on the thin film induced by the drops. Using the thin-film equation, we identify the scaling law for the spreading of the waves and demonstrate that this governs the range over which the interaction is observed.
Impact of induced magnetic field on free convective flow of kerosene/water based single and multiwalled carbon nanotubes
Authors: Kamran A. , Hussain S. , Sagheer M.
Published: October 2018

Mathematical analysis of single and multi-walled carbon nanotubes along with two different base fluids, water and kerosene oil, subjected to a strong magnetic field with induced magnetic field effects, has been carried out. The dimensionless equations describing the fluid motion, energy, angular momentum and the induced magnetic field of nanofluid have been solved numerically by the Keller box method. Heat transfer analysis reveals that a greater volume fraction of single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes (MWCNT) is responsible in enhancing the heat transfer rate as compared to the convectional fluid either its water or kerosene oil. In all the cases discussed through the graphs, it is seen that the heat transfer rate is greater in kerosene oil based nanofluid as compared with the water based nanofluid. It is found the greatest in the case of SWCNT-kerosene oil nanofluid and the least in the case of MWCNT-water.
NiAl as a potential material for liner- and barrier-free interconnect in ultrasmall technology node
Authors: Chen Linghan , Ando Daisuke , Sutou Yuji , Gall Daniel , Koike Junichi
Published: October 2018

Because of aggressive downscaling of the dimensions of future semiconductor devices, they will suffer from increased line resistivity and resistance-capacitance delay. In this work, NiAl thin films are investigated as a potential liner- and barrier-free interconnect material. The results show that NiAl has strong adhesion, does not undergo interdiffusion with SiO2, and has a favorable resistivity size effect. These features suggest that NiAl is a good candidate for replacing Cu as a liner- and barrier-free interconnect for linewidths below 7 nm.