bluuebunny/crossref_metadata_2025 huggingface dataset:
A model for high-mass microquasar jets under the influence of a strong stellar wind
Authors: Molina E. , del Palacio S. , Bosch-Ramon V.
Published: August 2019

Context. High-mass microquasars (HMMQs) are systems from which relativistic jets are launched. At the scales of several times the binary system size, the jets are expected to follow a helical path caused by the interaction with a strong stellar wind and orbital motion. Such a trajectory has its influence on the non-thermal emission of the jets, which also depends strongly on the observing angle due to Doppler boosting effects.

Aims. We explore how the expected non-thermal emission of HMMQ jets at small scales is affected by the impact of the stellar wind and the orbital motion on the jet propagation.

Methods. We studied the broadband non-thermal emission, from radio to gamma rays, produced in HMMQ jets up to a distance of several orbital separations, taking into account a realistic jet trajectory, different model parameters, and orbital modulation. The jet trajectory is computed by considering momentum transfer with the stellar wind. Electrons are injected at the position where a recollimation shock in the jets is expected due to the wind impact. Their distribution along the jet path is obtained assuming local acceleration at the recollimation shock, and cooling via adiabatic, synchrotron, and inverse Compton processes. The synchrotron and inverse Compton emission is calculated taking into account synchrotron self-absorption within the jet, free-free absorption with the stellar wind, and absorption by stellar photons via pair production.

Results. The spectrum is totally dominated by the jet over the counter-jet due to Doppler boosting. Broadband emission from microwaves to gamma rays is predicted, with radio emission being totally absorbed. This emission is rather concentrated in the regions close to the binary system and features strong orbital modulation at high energies. Asymmetric light curves are obtained owing to the helical trajectory of the jets.

Conclusions. The presence of helical shaped jets could be inferred from asymmetries in the light curves, which become noticeable only for large jet Lorentz factors and low magnetic fields. Model parameters could be constrained if accurate phase-resolved light curves from GeV to TeV energies were available. The predictions for the synchrotron and the inverse Compton radiation are quite sensitive of the parameters determining the wind-jet interaction structure.
Digging into the ancestral stocks of Jurassic lineages: ostracods (Crustacea) from Carnian (Late Triassic) sponge mounds from the Maantang Formation (South China)
Authors: Forel Marie-Béatrice , Thuy Ben , Wisshak Max
Published: August 2019

Microbial-sponge reef mounds of the Carnian, Late Triassic, Maantang Formation crop out along the northwestern margin of the Sichuan Basin in South China. Samples from three mounds have been investigated and their ostracod assemblages are here described for the first time. Thirty-three species are present, distributed into 19 genera, including five newly described species:Carinobairdiacabralaen. sp.,Hiatobairdia senegasin. sp.,Hiatobairdiazhengshuyingin. sp.,Hungarella gommeriin. sp,Pontocyprella goussardin. sp. While most of the encountered genera are already known from the Carnian stage worldwide, the Maantang assemblages are precursors in providing the oldest occurrences of the family Schulerideidae, typical of the Middle and Late Jurassic of Europe, and of the genusCarinobairdia, which was until now restricted to the Norian-Rhaetian interval. These records demonstrate the underestimated importance of the easternmost Tethys in the early Mesozoic evolution of marine ostracods. Some important Jurassic European taxa might have originated on the eastern margin of the Tethys during the Carnian, migrated to the western Tethys later during the Late Triassic and diversified there up to the record known for the European Jurassic. Microbioerosion trace fossil analysis of associated brachiopod shells revealedOrthogonum giganteumas the sole identifiable ichnotaxon and represents the first record of this ichnospecies in Triassic strata. The complete absence of microborings produced by phototrophic trace makers points towards aphotic depths for the deposition of the Maantang Formation, providing independent evidence suggesting that typical shallow water ostracods (Carinobairdia, Schulerideidae) radiated in relatively deep settings.
Wine consumption in China: profiling the 21st century Chinese wine consumer
Authors: García-Cortijo María Carmen , Villanueva Emiliano C. , Castillo-Valero Juan Sebastián , Li Yuanbo
Published: August 2019

This article determines the factors that influence Chinese wine consumption and, thus, contribute to define an average Chinese wine consumer profile for the years 2000 to 2014. The article proposes a model that explains the variations in the consumption of wine in China, because of traditional factors of the theory of demand (price of wine, income, and price of a substitute good), and sociodemographic factors (age, gender, marital status, level of education, geographical area, and tourism activities). The article reveals that an increased income, a married marital status, living in an urban area, and tourism activities, significantly and positively contributed to the increase of wine consumption in China. In addition, the article demonstrates that wine is not a substitute of beer in China, and that it is hard to associate an increase of wine consumption with the gender and the educational level of the average Chinese. In contrast, age negatively and significantly influenced the wine consumption in China, meaning that wine consumers are becoming younger.
Durability of self-healing concrete
Authors: De Belie Nele , Van Belleghem Bjorn , Erşan Yusuf Çağatay , Van Tittelboom Kim
Published: August 2019

Application of self-healing concrete reduces the need for expensive maintenance and repair actions. However, the durability of self-healing concrete has only been scarcely investigated. Here, recent results are presented regarding the resistance of self-healing concrete to chloride ingress. For self-healing concrete with macro-encapsulated polyurethane, chloride profiles and electron probe microanalysis indicated that this mechanism was efficient to reduce the chloride penetration into the crack and from the crack into the concrete matrix [1]. Furthermore, the corrosion behaviour of reinforced concrete specimens subjected to cyclic exposure with a NaCl solution was studied [2]. The electrochemical measurements indicated that autonomous crack healing could significantly reduce the corrosion in the propagation stage. No visual damage could be detected on the rebars after 44 weeks of exposure. On the contrary, cracked specimens without integrated self-healing mechanism, reached a state of active corrosion after 10 weeks of exposure and after 26 weeks clear pitting damage was observed on the rebars. While self-healing by encapsulated polyurethane is complete after one day, bacteria-based products take several weeks to heal a 300 µm crack. Bacterial granules containing denitrifying cultures released nitrite as an intermediate metabolic product which protected the reinforcement during the crack healing process [3].
The role of shrinkage reducing admixtures and supplementary cementitious materials in volume stability and strength development
Authors: Papayianni Ioanna , Kesikidou Fotini , Alt Philip Henes
Published: August 2019

Shrinkage is one of the main reasons for mortar and concrete failures like curling, crack formation and de-bonding. It is a complex phenomenon due to many factors involved, such as the type and amount of cement, water to binder ratio, binder to aggregates ratio and the type and granulometry of the aggregates, relative humidity, air temperature and the temperature of concrete. To reduce this phenomenon, Shrinkage Reducing Admixtures (SRAs) have been studied over the last 30 years. On the other hand, investigation in the field of Supplementary Cementitious Materials (SCMs) has indicated that their use in concrete may improve its volume stability depending on their percentage and the type of the material. In this paper, the addition of a Shrinkage Reducing Admixture and Supplementary Cementitious Materials like ladle furnace slag, calcareous fly ash and limestone filler, were investigated. Their influence, separately and in combination, in volume stability and strength development of cement mortars was identified. Capillary absorption and open porosity were also determined.
How concrete removal techniques affect the bonding between concrete and repair mortar
Authors: Yazdi Mohammad Ali , Dejager Elien , Debraekeleer Mats , Gruyaert Elke , Van Tittelboom Kim , De Belie Nele
Published: August 2019

Many bonding failures between the substrate and repair mortar are attributed to too aggressive removal of the contaminated concrete and incorrect use of repair materials. To this end, in this study the effect of concrete removal techniques on substrates of different compositions and, as a result, on the bonding with repair mortar has been investigated. Substrate surfaces of different concrete compositions, micro-concrete (MC) and crushed stone concrete (CC), were treated by using three commonly used techniques: grit blasting (GB), jack-hammering (JH), and hydrodemolition/water-jetting (WJ). Automated Laser Measurements (ALM), sand patch tests and surface tensile strength measurements were applied to characterize the substrate surface. According to the results, the co-lateral effects of removal techniques such as WJ are dependent on the concrete mix composition. Moreover, WJ- and JH- treated samples achieved a lower surface tensile strength and bond strength compared to GB-treated slabs.
Impressed current cathodic protection with embedded anodes – field trial on the Viaduc de Saint-Cloud in France
Authors: Bouteiller Véronique , Damien Guillaume , Boinski Frédéric , Schneider Julien , Michaux Christophe
Published: August 2019

This paper deals with the electrochemical repair of a road bridge, Viaduc de Saint-Cloud which was constructed in the 1970's in France. In 2011, a corrosion analysis was performed together with a durability study. It was demonstrated that the corrosion was induced by chloride ions coming from de-icing salts leaking from the deck. The induced corrosion was increased by the low cover depths resulting in a chloride penetration beyond the reinforcement depth. In order to evaluate the effectiveness and the reliability of Impressed Current Cathodic Protection (ICCP) with embedded anodes, a field trial was performed in 2012 on three span segments including one segment over pier (P2). The results of the ICCP design, the implementation and the monitoring are presented. It was found that two months were necessary before the cathodic protection would reach an equilibrium. Performance criteria as described in ISO 12696 dealing with cathodic protection passed on two segments but failed on the segment over pier. On the latter, where the congestion of reinforcement and prestressed tendons was higher, the anodic system needed some improvement. Finally, the results of the field trial allowed proposing a technical and an economic repair solution.
Zinc layer anode applied on reinforced concrete structures
Authors: Hallopeau Xavier , Moucadeau Eugène , Giorgini Roberto , Lesieutre Olivier , Meillier Arnaud , Annede-Villeau Camille
Published: August 2019

The application of zinc layer anode to reinforced concrete structure has been well known for many years. This galvanic cathodic protection system was specified being a corrosion control system for general steel in concrete as well as civil structures. A good way to determine the dimensioning elements of the galvanic protection system, is to carry out a pilot test being monitored in situ, and exposed under on site conditions including local concrete remediation or repair works. This paper presents an analysis of the current distribution and steel polarization data that have been collected from a car park project in the French Alps.
Residual protection on a wharf structure following application of impressed current cathodic protection
Authors: Bhuiyan Shamir , Law David , Nicholls Peter
Published: August 2019

Recent studies have suggested that residual protection is afforded to structures following the application of impressed current cathodic protection (ICCP), in some cases for significant periods of time, while others for periods of only a few days. This study reported the findings of the de-activation of a 20 year old ICCP system installed on a 50 year old structure. The ICCP was de-activated for 84 days and the steel potentials at locations on the front pile cap and front wall were monitored via the installed reference electrodes. An adjacent water anode system was also de-activated for 48 hours during the initial de-activation period to observe the impact on the steel potentials. The results showed that out of 42 reference electrodes, 17 achieved a 100 mv decay within 24 hours and 10 had more positive instant off potentials than -150 mV. Furthermore, all displayed a positive shift in potential following deactivation of the ICCP system for a period of time, indicative of residual protection, with 22 displaying this positive shift for the whole 94 days of the trial.
Cathodic protection of reinforcement in concrete – experience and development over 30 years
Authors: Polder Rob , Peelen Willy
Published: August 2019

This paper presents developments over 30 years in the field of cathodic protection of steel reinforcement in concrete in The Netherlands and elsewhere. From the late 1980s major developments have been: application to large numbers of precast elements corroding due to mixed-in chloride with drilled in titanium anodes and conductive coatings; analysis of working life of systems and components and end-of-life considerations; application to prestressed structures; new anode types including galvanic systems with associated life and design considerations; numerical modelling and preventative applications. Presently, CP has become a fully accepted method of securing safety and serviceability of buildings and infrastructure. Major successes and lessons learned will be presented. Technical and non-technical developments are highlighted and some recent innovative CP systems are discussed.
Monitoring and testing corrosion and responsive behaviour in galvanic systems.
Authors: Stone Christian , Glass Gareth , Roberts Adrian , Davison Nigel
Published: August 2019

Testing methods for corrosion prevention in structures have, historically, been based on the steel polarising from the protective current. Modern galvanic systems aim to protect the steel by restoring the protective alkaline environment, rather than through polarisation. Since 2012 standard guidelines allow for alternative testing to be used [1]. Scientific testing of galvanic systems will be discussed looking at the nature of constant potential galvanic systems and comparing them to the traditional constant current impressed systems, looking in particular at unique anode behaviours such as low median current during times of low corrosion risk and responsive behaviour during corrosion hazards. This work lays out a protocol for the evaluation and testing of existing galvanic corrosion protection (CP) systems in reinforced concrete through the lens of various real-world studies. Data taken from over a decade of monitored systems are used to support the protocol. Modern testing strategies such as 2-dimensional relative potential mapping and corrosion rate monitoring will measure the steel's corrosion. Galvanic currents rise and fall with corrosion risk providing protection while ensuring a long life to the design.
Results on the long-term performance and effectiveness of a galvanic CP system applied on a lightweight concrete bridge with prestressed steel as determined by depolarisation values and current densities
Authors: van den Hondel A.J. (Hans)
Published: August 2019

This paper gives insight in the research and investigations which were undertaken on a post tensioned light-weight concrete box girder bridge in the Netherlands. This project started in the first half of 2013 and measurements are still executed regularly. Due to long-term leakage of a longitudinal joint between 2 parts of the bridge, chlorides had penetrated into the concrete up to the level of the reinforcement and beyond, causing severe corrosion of the steel, spalling of the concrete cover and eventually causing danger for the shipping underneath the bridge due to falling lumps of concrete. To solve this problem, Galvanic Cathodic Protection (GCP) was applied in 2 stages. Firstly, in 2013, zinc based anode strips were applied on the soffit of 2 post tensioned lightweight bridge segments for the purpose of testing and monitoring. After obtaining good results from the test, in 2014/2015 the remaining 29 bridge segments were repaired and protected with the same GCP system as well. This paper reviews subsequent potential decay and current densities measurements, which have provided valuable information on GCP performance and throwing power. The results of anode performance at different locations and depths are reviewed. Concrete resistivity has shown a major influence on the effectiveness of the installed GCP system.
Hybrid fibre-reinforced geopolymer (HFRG) composites as an emerging material in retrofitting aging and seismically-deficient concrete and masonry structures
Authors: Guades Ernesto , Stang Henrik , Fisher Gregor , Schmidt Jacob
Published: August 2019

Fibre-reinforced polymer (FRP) systems have recently become popular in repairing concrete or masonry structures because of their inherent advantages. In spite of these benefits, FRPs have drawbacks having low fire resistance, poor environmental sustainability and incompatibilty with the substrate concrete. The effort to address these issues has led to the development of an emerging strain hardening cementitious (SHC) material using an inorganic polymer known as hybrid fibre-reinforced geopolymer (HFRG) composites. Compared with cement-based SHC composites, HFRG has better bond performance to concrete substrates, higher fire resistance, greater corrosion durability and helps to reduce CO2 emissions. This paper reviews the recent development of HFRG composites as an emerging repair material. Literature reveals that flowability of a fresh HFRG mixture decreases with increasing fibre content though still workable up to 2% fibre volume. Fibre synergy could result in 10–181% higher flexural toughness of geopolymer composites than when just using mono fibres. The application of HFRG composites to RC beams increased displacement ductility by to 263%. To date, there has been no reported field application of HFRG as a repair material though mono-fibre FRG has been field-applied as a strengthening material in large-diameter sewer RC pipes, RC culverts, RC sewerage manholes and dam surface improvement.
Experimental study regarding the influence of fibre to matrix compatibility on general performance of Fibre Engineered Cementitious Materials (FECM)
Authors: Mircea Anamaria , Mircea Călin , Szilágyi Henriette , Baeră Cornelia , Hegyi Andreea
Published: August 2019

Fibre Engineered Cementitious Materials (FECM) represent composites with similar overall performance as Engineered Cementitious Composites (ECC), namely developing strain hardening behaviour under loading, which generates the material capacity of high deformability. The pattern of multiple microcracks successively developed under increasing loading is proved to be the key of material self-consolidating potential and ability to support loads after the first crack occurrence. The matrix to fibre compatibility is considered to be one essential parameter controlling the multiple micro-cracking pattern (MC) and consequently, the strain hardening effect in the material. Factors like fibre type and reinforcement percent in the mixture represent sensitive variables, with major influence for matrix to fibre compatibility and overall performance of the composite. Cement based materials, whose compositional heterogeneity traditionally represents a lack in their regular usage, can be valorised and designed to produce the width controlled cracking typology, beneficial for material behaviour. This paper presents an experimental study on the fibre to matrix compatibility effect in the FECM design and producing process. Several types of dispersed reinforcing typologies for FECM development are experimentally tested and analysed. The results confirm the importance of matrix to fibre compatibility in enhancing superior material performance: physical, mechanical and even durability (Self-Healing potential evaluation).
Reinforced concrete corrosion prevention/reduction by hydrophobic impregnation
Authors: Donadio Michel , Bakalli Mirdash , Dan Zeno
Published: August 2019

The prevention of corrosion in reinforced concrete structures can be achieved by different means. The aim of this paper is to present the efficiency of corrosion prevention using silane hydrophobic impregnation, through laboratory investigations as well from long term field studies. The laboratory investigation was carried out in Zürich, is based on modified ASTM C109, where the product was applied on cracked concrete beams (before cracking and before corrosion initiation; after cracking and before corrosion initiation and finally after cracking and after corrosion initiation). The long term field studies were carried out over 12-years exposure to de-icing salts in a Swiss tunnel, and after 10 years exposure to a marine zone simulation in Japan. This paper will show that the use of a silane hydrophobic impregnation can be an effective way to reduce the risk of corrosion for concrete structures, including structures exposed to chlorides in a marine environment, or from the use of de-icing salts in winter time.
Performance of patch repairs on historic concrete structures: a preliminary assessment
Authors: Arato Gonçalves Ana Paula , Macdonald Susan , Marie-Victoire Élisabeth , Bouichou Myriam , Wood Chris
Published: August 2019

Carrying out patch repairs to historic concrete buildings and structures needs to be done carefully if their cultural value and significance is to be maintained. This often means repairs using custom designed materials and mixes for compatibility with the original concrete, and with great care paid to good workmanship. But with most repairs, commercial mixes are used which are not compatible with the host concrete but are justified because they adhere well, cure quickly and require limited skills to implement. A research collaboration has been established to test the performance of both approaches. The Performance Evaluation of Patch Repairs on Historic Concrete Structures (PEPS) began in 2018 and is a collaboration between the Getty Conservation Institute, Historic England and the Laboratoire de Recherche des Monuments Historiques. Its purpose is also to better understand key design and specification parameters and application methods. The research is based on assessing case studies in USA, England and France within a variety of climatic and environmental conditions, typologies and repair materials. This paper will present the methodology adopted to evaluate the repairs in the first phase. This will also include historical research on the specification and application of the repairs, preliminary field assessment and some testing.
The influence of SAPs on chloride ingress in cracked concrete
Authors: Van Mullem Tim , Caspeele Robby , De Belie Nele
Published: August 2019

Super Absorbent Polymers (SAPs) have proven to be effective as a self-healing agent for regaining the liquid tightness of cracked concrete. This is due to their large swelling capacity which allows them to (partially) block cracks which are in contact with water or moisture. Additionally, they are able to release this water when the climate becomes drier, thereby promoting the autogenous healing capacity of the concrete matrix. The effect SAPs have on chloride migration into cracked concrete is still unknown. The swelling capacity of the SAPs might partially block the crack, but this does not necessarily mean that the chloride ingress into the crack is lower. Especially, since the porosity of concrete with SAPs is slightly higher when additional water is added to compensate for the loss in workability. This paper compares the chloride ingress in cracked mortar with and without SAPs. The specimens were saturated in a chloride solution during 1 or 5 weeks after which the chloride ingress could be visualised using silver nitrate. The specimens which healed prior to chloride saturation had a significantly lower chloride ingress. The SAPs were able to delay the chloride ingress, as well as limit the influence of the crack on the chloride ingress.
Modelling the behaviour of concrete shear walls with BFRP reinforcement
Authors: Rahman Hamid , Donchev Ted , Petkova Diana
Published: August 2019

Corrosion of steel reinforcement in concrete structures is one of the main challenges for the construction industry. FRP reinforcement could be used as alternative to steel reinforcement providing several advantages, such as high resistance to corrosion, high tensile strength and opportunity for developing a more ductile mode of destruction. The last characteristic is extremely beneficial in the aspect of lateral load resisting systems including RC shear walls. The presented modelling results consist of preparing finite element models of reinforced concrete shear walls utilizing Ansys 19.2 - Solid65 element which is capable of both cracking and crushing. The results were verified with experimental medium-scale concrete shear walls reinforced with steel and BFRP bars. The models were loaded under cyclic lateral loading following a modified ATC (Applied Technology Council guidelines for seismic testing) 24 protocol. BFRP reinforced models developed similar ultimate capacity and significantly higher energy dissipation in comparison with steel reinforced models. The promising results could provide a momentum toward construction of shear walls using FRP reinforcement with the aims of improving durability and energy dissipation.
Durability of concretes prepared with crystalline admixtures
Authors: Sideris Kosmas K. , Chatzopoulos A. , Tassos Ch. , Manita P.
Published: August 2019

The objective of this work was to study the influence of crystalline admixtures on the durability of concrete. Four concrete mixtures – two reference concretes and two alternative mixtures-were produced during the first phase of the research. Influence of curing on the activation of the crystals was investigated on concrete slab specimens. The properties measured were the compressive strength and different durability indicators. The results revealed that crystalline admixtures enhanced the strength and the durability of the alternative mixtures.
Hybrid sandwich panels for building uses: focus on glass fibre reinforced polymer and mineral matrix interface.
Authors: Djama Khaled , Michel Laurent , Ferrier Emmanuel , Gabor Aron
Published: August 2019

Sandwich structures are being used increasingly in civil engineering because of their high strength, stiffness, and stiffness-to-density ratio. The studied sandwich structure was made of glass fibre reinforced polymer (GFRP) skins, and GFRP reinforced core. Two case studies are presented in this paper: a use as lightweight floor in building rehabilitation, and an application as façade panels. In both cases, the GFRP sandwich structure can be associated with a mineral matrix because of conventional construction methods and acoustic floor insulation in the first case, and because of architectural issues in the second. To design the hybrid sandwich panel and ensure monolithic mechanical behaviour, a finite element method (FEM) that predicts the interface failure was introduced. To implement the FE model by mechanical interface properties, pull-off and push-out tests were performed to assess the mode I and mode II stress limits. Four GFRP surface roughnesses and two configurations with chemical additions were tested. The three configurations that performed the best were tested by submitting the hybrid sandwich structure to three-point bending loading. The prediction of the interface failure by the FEM was assessed by comparison to the experimental data. Finally, full-scale panels were experimentally tested and designed for the named two uses cases thanks to the FE model.
Corrosion at low moisture content in both carbonated and chloride polluted concrete – Villa E-1027, a case study
Authors: Marie-Victoire Elisabeth , Bouichou Myriam
Published: August 2019

Corrosion in reinforced concrete is generally attributed to either carbonation or chloride presence in the vicinity of the bars. But in the field of cultural heritage, especially for the most ancient monuments, it is not rare to encounter both carbonated and chloride polluted concrete, inducing heavy corrosion, as was the case in the Villa E-1027 in Roquebrune-Cap-Martin, on the French Mediterranean seashore. The villa was designed by Eileen Gray and Jean Badovici between 1926 and 1929. Due to aggressive environmental conditions and a period of dereliction, the concrete of the villa was quite heavily decayed and a deep restoration was led between 2000 and 2006. But after a little more than 10 years, and despite active maintenance, the villa is again facing corrosion induced decay. Prior to the definition of a new restoration protocol, to better evaluate the corrosion activity, in 2017 a permanent monitoring of moisture and temperature both in the air and in the concrete was installed. In the meantime, a series of instant electrochemical measurements was performed from 2017 to 2018. A first analysis of the results of the monitoring and the non-destructive tests clearly evidences that probably due to the conjunction of the carbonation of the concrete and external active chloride pollution, corrosion can happen at quite low moisture content.
CAD-based Approach for Identification of UAVs
Authors: Grau Antoni , Bolea Yolanda , Sanfeliu Alberto
Published: August 2019

The paper presents an approach for the identification of the parameters of an Unmanned Aerial Vehicle (UAV), specifically a quadrotor using experiments in a CAD environment. A linearized control model is proposed to create a global model that operates in all operation range. Usually, in this type of systems a linear time invariant (LTI) controller is used, and then a lineal control model around each operating point is needed to the design of the controller. In this study, a linear control model suitable in each operating point is developed and identified. This serial of LTI control model can be combined and provides a global control model. Therefore, through this global control model can be designed a global controller suitable for all the operating range.
Comparative Analysis and Development Exploration of Threat Assessment Methods for Warship Air Defense
Authors: Yu Pingbo , Liu Gaofeng , Gong Li
Published: August 2019

Warship’s air defense target threat assessment is an uncertainty issue. This paper briefly states the basic process and types of threat assessment methods for warship air defense, using comparative research method, the mechanism and characteristics of the certainty/uncertainty assessment method for target threat assessment are compared. It also analyzes the application of fuzzy theory, neural network and genetic fuzzy tree in target threat assessment, which has certain reference value for the research of warship air defense target threat assessment.
A Novel Concept of Electromagnetic Pressure Sensor based on Impedance Variation for Pneumatic Applications
Authors: Alina Popescu-Cuta , Daniel Comeaga Constantin , Alexandru Dobre Alin
Published: August 2019

The core concept of the proposed sensor relies on the architecture of a new type of microscale electromagnetic actuator, previously developed and tested. Previous studies were focus on conceptual design, modelling and simulation and application as an actuator for static and dynamic purposes. Upon presenting the device functioning principle and design, the authors propose a new application of this device, as a detection element, due to its electrodynamic behavior that allows the correlation of displacements and deformations with the variation of the device coil inductance. This dependency could also be used as a feedback information, allowing a closed loop control without an aditional sensorial element. A series of numerical models have been developed and computed in order to test the sensorial properties of the device and to describe the functioning principle as a detection element. The models have been computed using two materials for the sensor’s mobile element, to test if the manufacturing costs can be lowered by using a material without magnetic properties and the conclusions of the studies have also been drawn. Once the sensor behavior and the structural materials have been concluded, a sensor model has been developed and studied using FEM. Further on, one of the sensor constructive parameters has been varied in relation to the desired measuring range and the future research directions have been drawn.
Optimization of generalized order-level inventory system under fully permissible delay in payment
Authors: Mondal Bappa , Garai Arindam , Roy Tapan Kumar
Published: August 2019

This article presents one generalized order-level inventory system with fully permissible delay in payment in various trade-credit intervals. Review of existing literature finds few EOQ models under simultaneous considerations of time-dependent generalized demand rate, time-dependent generalized rate of deterioration and time-dependent generalized backordering under fully permissible delay in payment. In those existing studies, the optimal inventory depletion time is independent of demand over the entire cycle. Here, present article frames one generalized order-level inventory system with fully permissible delay in payment across various trade-credit intervals. This finds that when the trade-credit period is longer than the inventory depletion time to settle the account, the optimal inventory depletion time is dependent of demand. Under this ambiance, one particular case having time-dependent ramp type demand rate, two variables time-dependent Weibull distribution rate of deterioration and time-dependent backordering rate with fully permissible delay in payment, finds that the optimal inventory depletion time varies inversely over demand in that period. Moreover, the proposed model shrinks to obtain many well-established EOQ models as the special cases to it. Next, a general algorithm determines the various optimal solutions corresponding to seven cases. The managerial insights extracted from sensitivity analysis of parameters include the suggestion to halt the promotional activities so as to foreshorten the demand in shortage period. Also, this analysis attests that the longer waiting period of retailers should be counterbalanced with various promotional activities and anticipated benefits.
Acetabular liner dissociation: A case report and review of the literature
Authors: Parkar Asif A.H. , Sukeik Mohamed , El-Bakoury Ahmed , Powell James
Published: August 2019

Dissociation of the polyethylene liner from the acetabular shell is a rare but catastrophic complication of total hip arthroplasty (THA). There have been reports of polyethylene liner dissociation (PLD) as well as ceramic liner dissociation (CLD) in the literature. Amongst the commonly used implants, liner dissociation has been reported with the Pinnacle (DePuy), Harris–Galante (Zimmer) and Trident (Stryker) acetabular components.

To the best of our knowledge, this is the first case report of PLD in an R3 (Smith & Nephew) acetabular component. This case report highlights the implant choice for treatment of the liner dissociation and the role of constrained implants in such cases.
Evaluation der intratherapeutischen Dosimetrie bei der 177Lu-HA-DOTATATE Therapie neuroendokriner Tumoren mittels SPECT, Ganzkörperszintigraphie und Gammasonde
Authors: Leonhäuser Britta , Happel Christian , Gröner Daniel , Bockisch Benjamin , Fiebich Martin , Hellwig Dirk , Grünwald Frank , Kranert Wolfgang Tilman
Published: August 2019

Ziel Bei der Behandlung somatostatinrezeptor-exprimierender neuroendokriner Tumoren hat sich in den letzten Jahren die Peptidrezeptor-Radionuklidtherapie (PRRT) mit 177Lu-HA-DOTATATE als neue Möglichkeit entwickelt. Da außer Tumor und Metastasen auch die Nieren Somatostatinrezeptoren besitzen, die Aktivität in diesen akkumuliert, sind sie als Risikoorgane einzustufen und sollten dosimetrisch evaluiert werden. Die Bestimmung der Nierenaktivität aus planaren Aufnahmen ist durch Überlagerung der Nieren mit anderen Organen ungenau und führt zu ihrer Dosisüberschätzung. Ziel dieser Studie war es, den Beitrag der Nieren in den konjugierten Sichten ohne SPECT/CT in der individuellen Nierendosimetrie zu berücksichtigen.

Material und Methoden Für die Bestimmung der Nierendosis wurde ein Algorithmus entwickelt, der mit EXCEL (Microsoft) umgesetzt wurde. Die Patientenmessdaten aus drei Modalitäten einer individuell kalibrierten Gammasonde, einem Ganzkörperszintigramm und drei SPECT-Akquisitionen zu verschiedenen Zeitpunkten wurden hierfür zusammengeführt. Die Methode wurde mit Daten von 85 Nieren von Patienten, die mit 177Lu-HA-DOTATATE behandelt worden waren, evaluiert. Die Nierenvolumina wurden mittels CT-Volumetrie gewonnen.

Ergebnisse Der entwickelte Algorithmus kombiniert die Daten aus drei Modalitäten: Gamma-Sonde, SPECT und Ganzkörperszintigraphie. Der Quotient aus den Ereignissen der Nieren-VOI und der Anzahl der Ereignisse in der Nieren-ROI des koronaren Summationsbildes ist der Beitrag der Niere im Summationsbild und repräsentiert somit über die Kalibrierung aus der Ganzkörperszintigraphie die Aktivität in der Niere. Da die Abbildungseigenschaften in den SPECT-Akquisitionen zu den verschiedenen Zeiten konstant sind, folgt aus dem Verlauf der Zählraten in den jeweiligen Nieren-VOIs auch der Aktivitätsverlauf in den Nieren. Daraus kann über einen monoexponentiellen Fit der Aktivitätsausscheidung unter Berücksichtigung der Akkumulationskinetik die Nierendosis bestimmt werden. Der mittlere Anteil in der Niere, bezogen auf deren Projektion im Summationsbild, wurde mit 49 % (17 %–78 %) und 45 % (18 %–75 %) für die linke bzw. rechte Niere berechnet. Die sich daraus ergebenden Nierendosen lagen zwischen 0,13 und 0,77 Gy/GBq (Mittelwerte 0,36 Gy/GBq und 0,39 Gy/GBq für die linke und die rechte Niere).

Schlussfolgerung Die vorgestellte Methode eignet sich, um mit Gammasonde und Szintigraphie/SPECT (auch ohne SPECT/CT), eine individuelle Nierendosimetrie durchzuführen.
Current Treatment Options in Acute Limb Ischemia
Authors: Fluck Friederika , Augustin Anne Marie , Bley Thorsten , Kickuth Ralph
Published: August 2019

Background Acute limb ischemia represents a clinical emergency with eventual limb loss and life-threatening consequences. It is characterized by a sudden decrease in limb perfusion. Acute ischemia is defined as a duration of symptoms for less than 14 days. Aging of the population increases the prevalence of acute limb ischemia. The two principal etiologies are arterial embolism and in situ thrombosis of an atherosclerotic artery. Immediate diagnosis, accurate assessment and urgent intervention when needed are crucial to save the limb and to prevent a major amputation. Delay in diagnosis and therapy may lead to irreversible ischemic damage.

Method To assess the current treatment options in acute limb ischemia, this review is based on a selective literature search in PubMed representing the current state of research.

Results and Conclusion Patients with acute limb ischemia should receive immediate anticoagulation. Treatment depends on the classification based on the degree of ischemia and limb viability. Especially acute (< 14 days symptom duration) Rutherford Categories IIa and IIb with marginally and immediately threatened limbs require definitive therapeutic intervention and are salvageable, if promptly revascularized. The current literature suggests that open surgical revascularization is more time effective then catheter-directed thrombolysis. However, with the advent of thrombolytic delivery systems and mechanical thrombectomy devices, treatment time can be minimized and successful utilization in patients with Category IIb (Rutherford Classification for Acute Limb Ischemia) has been reported with promising limb-salvage and survival rates. Large randomized studies are still missing, and guidelines suggest choosing the method of revascularization depending on anatomic location, etiology, and local practice patterns, with the time to restore the blood flow being an important factor to consider.

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Citation Format
Samarium Diiodide Catalyzed Radical Cascade Cyclizations that Construct Quaternary Stereocenters
Authors: Huang Huan-Ming , He Qiong , Procter David J.
Published: August 2019

SmI2-catalyzed radical cascade cyclizations were used to generate complex carbocyclic products bearing quaternary stereocenters with high selectivity. Bicyclic scaffolds containing four contiguous stereocenters and one quaternary stereocenter were obtained in excellent yields (up to 99%) and with high diastereocontrol by using 5 mol% of SmI2 at ambient temperature in the absence of co-reductants or additives. Mechanistic studies support a radical relay mechanism.
Goniometer for determination of the spectrally resolved scattering phase function of suspended particles
Authors: Nothelfer S. , Foschum F. , Kienle A.
Published: August 2019

An apparatus for direct determination of the spectral resolved scattering phase function of suspensions and emulsions is described. The system consists of a polychromatic xenon lamp as a light source and a spectrometer as a detector. Together with a stepper motor, the system enables spectrally and angularly resolved measurements in the range of 450 nm–950 nm and 10°–170°, respectively. A model for light propagation inside the cuvette in the regime of single scattering, which also takes the spectral dimension into account, was developed. A postprocessing algorithm applying the model and an extrapolation to the measured angular data allows a direct determination of the complete scattering phase function. By comparing measurements on polystyrene microspheres with Mie theory, the concept of the presented instrument was validated. Finally, the method was used to determine the scattering phase function of different types and brands of soybean oil emulsions such as Intralipid or Lipovenös. The measured scattering phase functions were then used to calculate the corresponding Legendre moments to an order of 20 and for wavelengths between 450 nm and 750 nm (available online), which besides the anisotropy factor also allow the determination of higher order factors such as gamma.
Enhanced thermoelectric figure of merit in Bi2Te3–CNT–PEDOT nanocomposite by introducing conducting interfaces in Bi2Te3 nanostructures
Authors: Kumar Sunil , Chaudhary Deepti , Khare Neeraj
Published: August 2019

Bi2Te3–CNT–PEDOT nanocomposites have been synthesized by mixing PEDOT:PSS with hydrothermally synthesized Bi2Te3–CNT nanocomposites. Introducing conducting interfaces by adding PEDOT in Bi2Te3–CNT boosts the charge carrier mobility, resulting in improved electrical conductivity and simultaneously lowering the lattice thermal conductivity by enhancing phonon scattering and thus resulting in two-fold enhancement of the figure of merit. The detailed mechanism behind the enhancement of charge carrier mobility is discussed by considering the role of conducting interfaces and strong coupling of CNTs and PEDOT conducting chains. The formation of a large number of interfaces in Bi2Te3–CNT–PEDOT nanocomposites acts as strong scattering centers and thermal barriers for long-wavelength phonons, which reduces the lattice thermal conductivity. The formation of interfaces between Bi2Te3 nanostructures and CNT–PEDOT conducting channels has been studied by Kelvin probe force microscopy which clearly showed a smaller interface potential barrier for the Bi2Te3–CNT–PEDOT nanocomposite.
Existence and multiplicity of positive solutions for fractional Laplacian systems with nonlinear coupling
Authors: Che Guofeng , Chen Haibo , Wu Tsung-fang
Published: August 2019

It is well known that a single nonlinear fractional Schrödinger equation with a potential V (x) may have a positive solution that is concentrated at the nondegenerate minimum point of V (x) when the positive parameter ε is sufficiently small [see G. Chen and Y. Zheng, Commun. Pure Appl. Anal. 13, 2359 (2014); J. Dávila et al., J. Differential Equations 256, 858 (2014); and M. M. Fall et al., Nonlinearity 28, 1937 (2015)]. In this work, we find multiple different positive solutions for a class of weakly coupled fractional Schrödinger systems with two potentials V1(x) and V2(x) that have some of the same minimum points; the positive solutions are concentrated at these minimum points. By using energy estimates, the Nehari manifold technique, and the Lusternik–Schnirelmann theory of critical points, we obtain some multiplicity results for a class of weakly coupled fractional Schrödinger systems. The existence and nonexistence of least energy positive solutions are also explored.
Heusler interfaces—Opportunities beyond spintronics?
Authors: Kawasaki Jason K.
Published: August 2019

Heusler compounds, in both cubic and hexagonal polymorphs, exhibit a remarkable range of electronic, magnetic, elastic, and topological properties, rivaling that of the transition metal oxides. To date, research on these quantum materials has focused primarily on bulk magnetic and thermoelectric properties or on applications in spintronics. More broadly, however, Heuslers provide a platform for discovery and manipulation of emergent properties at well-defined crystalline interfaces. Here, motivated by advances in the epitaxial growth of layered Heusler heterostructures, I present a vision for Heusler interfaces, focusing on the frontiers and challenges that lie beyond spintronics. The ability to grow these materials epitaxially on technologically important semiconductor substrates, such as GaAs, Ge, and Si, provides a direct path for their integration with modern electronics. Further advances will require new methods to control the stoichiometry and defects to “electronic grade” quality and to control the interface abruptness and ordering at the atomic scale.
Stackelberg game under asymmetric information in critical infrastructure system: From a complex network perspective
Authors: Zeng Chengyi , Ren Baoan , Li Menglin , Liu Hongfu , Chen Jing
Published: August 2019

Modern society is highly dependent on critical infrastructures. Since many infrastructures have network functions, it is necessary to study them from the perspective of network science. Game theory provides a suitable framework to model the confrontations in critical infrastructures. Previous models that combine network science with game theory only consider the condition of complete information. However, in the real world, complete information about the target network is not always available to the attacker. In this paper, we achieve active defense by revealing the disguised network to the attacker rather than changing the structure of the target network. We first introduce a false network generation method and investigate the transformation of the node degree in the created network. Furthermore, we propose a Stackelberg game under asymmetric information named the active deception game, in which the cost constraint is considered. Experiments based on the synthetic scale-free network indicate that disclosing false information to the attacker yields a higher equilibrium payoff than revealing complete information. We analyze the equilibrium strategies and show an interesting but counterintuitive finding that the attacker tends to choose high-degree nodes, but the defender prefers selecting low-degree nodes when the attacker does not have a global dominance strategy. Our work provides a new approach to the proactive defense of infrastructure networks using information asymmetry between attack and defense sides, which deserves further study.