bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhanced photocurrent in organic photodetectors by the tunneling effect of a hafnium oxide thin film as an electron blocking layer
Authors: Ji Chan Hyuk , Lee Ji Young , Kim Kee Tae , Oh Se Young
Published: September 2019

To achieve high detectivity of organic photodetectors (OPDs), we investigated hafnium oxide (HfO2) as an electron blocking layer in an attempt to obtain a low leakage current and high photocurrent by the tunneling effect.
KOtBu-promoted oxidative dimerizations of 2-methylquinolines to 2-alkenyl bisquinolines with molecular oxygen
Authors: Wang Zhen , Zhang Jinjin , Shi Jianxue , Wang Huiqiao
Published: September 2019

KOtBu-promoted oxidative dimerizations of 2-methylquinolines with molecular oxygen as the oxidant have been developed for the first time.
Rutin-modified silver nanoparticles as a chromogenic probe for the selective detection of Fe3+in aqueous medium
Authors: Coutinho Mayra S. , Latocheski Eloah , Neri Jannyely M. , Neves Ana C. O. , Domingos Josiel B. , Cavalcanti Lívia N. , Gasparotto Luiz H. S. , Moraes Edgar P. , Menezes Fabrício G.
Published: September 2019

The use of rutin-modified silver nanoparticles for selective detection and sensitive quantification of Fe3+in aqueous solution is described.
Interaction of single- and double-stranded DNA with multilayer MXene by fluorescence spectroscopy and molecular dynamics simulations
Authors: Manzanares-Palenzuela C. Lorena , Pourrahimi Amir M. , Gonzalez-Julian J. , Sofer Zdenek , Pykal Martin , Otyepka Michal , Pumera Martin
Published: September 2019

MXenes show differential affinity towards single- and double-stranded DNA, with unique kinetics and potential for fluorescent biosensing.
Synergistic catalysis on Fe–Nx sites and Fe nanoparticles for efficient synthesis of quinolines and quinazolinones via oxidative coupling of amines and aldehydes
Authors: Ma Zhiming , Song Tao , Yuan Youzhu , Yang Yong
Published: September 2019

A heterogeneous nanocomposite of Fe–Fe3C nanoparticles and Fe–Nx sites on N-doped porous carbon allows for efficient synthesis of quinolines and quinazolinones via oxidative coupling of amines and aldehydes in aq. solution using H2O2 as the oxidant.
Exciplex emissions derived from exceptionally long-distance donor and acceptor molecules
Authors: Pu Yong-Jin , Koyama Yuki , Otsuki Daisuke , Kim Minjun , Chubachi Hiroya , Seino Yuki , Enomoto Kazushi , Aizawa Naoya
Published: September 2019

We report exceptionally long-distance coupled exciplex emissions between electron-donor and electron-acceptor molecules even with a 70 nm-thick spacer layer.
Molecular tunability of surface-functionalized metal nanocrystals for selective electrochemical CO2 reduction
Authors: Pankhurst James R. , Guntern Yannick T. , Mensi Mounir , Buonsanti Raffaella
Published: September 2019

Disubstituted imidazolium compounds are used as ligands to promote the CO2RR at the surface of Ag nanocrystal catalysts. Catalyst performance is fine-tuned at the molecular scale through systematic variation of the imidazolium substituents.
Current progress of Pt and Pt-based electrocatalysts used for fuel cells
Authors: Ren Xuefeng , Lv Qianyuan , Liu Lifen , Liu Bihe , Wang Yiran , Liu Anmin , Wu Gang
Published: September 2019

Due to the growing demand for energy and impending environmental issues, fuel cells have attracted significant attention as an alternative to conventional energy technologies.
Unlocking the potential of BECCS with indigenous sources of biomass at a national scale
Authors: Zhang Di , Bui Mai , Fajardy Mathilde , Patrizio Piera , Kraxner Florian , Dowell Niall Mac
Published: September 2019

Secondary sources of biomass (forest residue, crop residue, MSW and waste wood) will play an important role in improving the negative emissions potential of BECCS by reducing carbon emissions along the biomass supply chain.
Hexaazatriphenylene-based polymer cathode for fast and stable lithium-, sodium- and potassium-ion batteries
Authors: Kapaev Roman R. , Zhidkov Ivan S. , Kurmaev Ernst Z. , Stevenson Keith J. , Troshin Pavel A.
Published: September 2019

An organic polymer was shown to be a universal cathode for fast and stable Li-, Na- and K-ion batteries.
A carbon nanotube-confined iron modified cathode with prominent stability and activity for heterogeneous electro-Fenton reactions
Authors: Su Pei , Zhou Minghua , Ren Gengbo , Lu Xiaoye , Du Xuedong , Song Ge
Published: September 2019

We demonstrate the importance of confinement catalysis in selectively controlling the position and valence of iron on CNTs, which could effectively increase heterogeneous electro-Fenton activity and decrease iron leaching to improve cathode stability.
Unique chemistries of metal-nitrate precursors to form metal-oxide thin films from solution: materials for electronic and energy applications
Authors: Cochran Elizabeth A. , Woods Keenan N. , Johnson Darren W. , Page Catherine J. , Boettcher Shannon W.
Published: September 2019

Unique chemistries of metal-nitrate precursors that enable the preparation of high-quality, high-performance metal-oxide thin films by solution deposition are reviewed.
Clarifying the controversial catalytic active sites of Co3O4 for the oxygen evolution reaction
Authors: Xu Yong , Zhang Fengchu , Sheng Tian , Ye Tao , Yi Ding , Yang Yijun , Liu Shoujie , Wang Xi , Yao Jiannian
Published: September 2019

Controversial results still exist about the activities of tetrahedral (Co2+) and octahedral (Co3+) sites in Co3O4 toward the OER. Theoretical and experimental data confirm that octahedral sites are responsible for the OER, using model catalysts.
Dendrite-free lithium–metal batteries at high rate realized using a composite solid electrolyte with an ester–PO4 complex and stable interphase
Authors: Zhang Zhaoshuai , Zhang Long , Liu Yanyan , Yang Tingting , Wang Zhiwen , Yan Xinlin , Yu Chuang
Published: September 2019

PO43−–ester interactions realize dendrite-free Li deposition in PCL–LAGP, evidenced by galvanostatic cycling and in situ TEM observations. The corresponding battery achieves high coulombic efficiency ∼100% and a rate capability ≥10C.
Understanding the effects of chemical reactions at the cathode–electrolyte interface in sulfide based all-solid-state batteries
Authors: Jung Sung-Kyun , Gwon Hyeokjo , Lee Seok-Soo , Kim Hyunseok , Lee Jae Cheol , Chung Jae Gwan , Park Seong Yong , Aihara Yuichi , Im Dongmin
Published: September 2019

Driven by a paradigm shift from conventional liquid-based systems to all-solid-state batteries (ASSBs), the chemo-mechanical behavior of the solid–solid interface is of growing importance for understanding the intricate interfacial phenomena of ASSBs.
An intercalation pseudocapacitance-driven perovskite NaNbO3 anode with superior kinetics and stability for advanced lithium-based dual-ion batteries
Authors: Yan Tong , Ding Rui , Ying Danfeng , Huang Yongfa , Huang Yuxi , Tan Caini , Sun Xiujuan , Gao Ping , Liu Enhui
Published: September 2019

A perovskite NaNbO3 anode with a pseudocapacitive intercalation mechanism exhibits superior kinetics and stability for advanced lithium-based dual-ion batteries.
A blade-coated highly efficient thick active layer for non-fullerene organic solar cells
Authors: Zhang Lin , Zhao Heng , Lin Baojun , Yuan Jian , Xu Xianbin , Wu Jingnan , Zhou Ke , Guo Xia , Zhang Maojie , Ma Wei
Published: September 2019

Highly efficient large-area thick-film organic solar cells were fabricated by blade-coating with finely controlling the molecular packing.
Chiral EDT-TTF precursors with one stereogenic centre: substituent size modulation of the conducting properties in the (R-EDT-TTF)2PF6 (R = Me or Et) series
Authors: Mroweh Nabil , Auban-Senzier Pascale , Vanthuyne Nicolas , Canadell Enric , Avarvari Narcis
Published: September 2019

The first enantiopure monoalkylated EDT-TTF derivatives provided mixed-valence chiral radical cation salts showing metallic or semiconducting character.
Engineering carbon quantum dots for enhancing the broadband photoresponse in a silicon process-line compatible photodetector
Authors: Sarkar K. , Devi Pooja , Lata A. , Ghosh R. , Kumar Praveen
Published: September 2019

Realization of heterojunction based broadband photodetectors (ultraviolet to near-infrared) compatible with existing silicon process technology has great promise for advanced optoelectronic applications.
Helicobacter pylori helicase loader protein Hp0897 shows unique functions of N- and C-terminal regions
Authors: Kumar Ajay , Saha Abhik , Verma Vijay K. , Dhar Suman Kumar
Published: September 2019

Helicase loaders are required for the loading of helicases at the vicinity of replication origins. In Helicobacter pylori, Hp0897 has been shown to be a potential helicase loader for replicative helicase (HpDnaB) although it does not show any sequence homology with conventional DnaC like helicase loader proteins. Therefore, it is important to investigate the in vivo role of Hp0897 and structure-function analysis with respect to domain mapping of Hp0897 and HpDnaB. Although HporiC is divided into oriC1 and oriC2, the latter has been assigned as functional origin based on loading of initiator protein HpDnaA. Using chromatin immunoprecipitation (ChIP) experiment, we show preferential binding of Hp0897 at oriC2 over oriC1 like HpDnaA highlighting its helicase loader function in vivo. Furthermore, we generated series of deletion mutants for HpDnaB and Hp0897 that enabled us to map the domains of interaction between these two proteins. Interestingly, the C-terminal domain of Hp0897 (Hp0897CTD) shows stronger interaction with HpDnaB over the N-terminal region of Hp0897 (Hp0897NTD). Similar to the full-length protein, Hp0897CTD also stimulates the DNA binding activity of HpDnaB. Furthermore, overexpression of Hp0897 full-length protein in H. pylori leads to an elongated cell phenotype. While the overexpression of Hp0897CTD does not show a phenotype of cell elongation, overexpression of Hp0897NTD shows extensive cell elongation. These results highlight the possible role of Hp0897CTD in helicase loading and Hp0897NTD's unique function linked to cell division that make Hp0897 as a potential drug target against H. pylori.
Biochemical characterization of phosphoenolpyruvate carboxykinases from Arabidopsis thaliana
Authors: Rojas Bruno E. , Hartman Matías D. , Figueroa Carlos M. , Leaden Laura , Podestá Florencio E. , Iglesias Alberto A.
Published: September 2019

ATP-dependent phosphoenolpyruvate carboxykinases (PEPCKs, EC 4.1.1.49) from C4 and CAM plants have been widely studied due to their crucial role in photosynthetic CO2 fixation. However, our knowledge on the structural, kinetic and regulatory properties of the enzymes from C3 species is still limited. In this work, we report the recombinant production and biochemical characterization of two PEPCKs identified in Arabidopsis thaliana: AthPEPCK1 and AthPEPCK2. We found that both enzymes exhibited high affinity for oxaloacetate and ATP, reinforcing their role as decarboxylases. We employed a high-throughput screening for putative allosteric regulators using differential scanning fluorometry and confirmed their effect on enzyme activity by performing enzyme kinetics. AthPEPCK1 and AthPEPCK2 are allosterically modulated by key intermediates of plant metabolism, namely succinate, fumarate, citrate and α-ketoglutarate. Interestingly, malate activated and glucose 6-phosphate inhibited AthPEPCK1 but had no effect on AthPEPCK2. Overall, our results demonstrate that the enzymes involved in the critical metabolic node constituted by phosphoenolpyruvate are targets of fine allosteric regulation.
Predictors of Comfort Level in Speech-Language Pathologists Working With Students With Attention-Deficit/Hyperactivity Disorder
Authors: Roitsch Jane , Phalen Lisa , Watson Silvana M. R.
Published: September 2019

Purpose

Students with attention-deficit/hyperactivity disorder (ADHD) often demonstrate language deficits requiring speech-language pathologist (SLP) interventions. With the number of students diagnosed with ADHD on the rise, SLPs are being called upon increasingly to address the needs of these students. Ensuring SLPs are comfortable treating students with ADHD is of growing importance. To date, there is limited evidence examining what factors may predict how comfortable SLPs are working with students with ADHD. This study investigated the relationships between variables to better predict comfort levels of school SLPs in their management of students with ADHD.

Method

A total of 86 school SLPs from the American Speech-Language-Hearing Association's Special Interest Groups 1 (Language, Learning and Education) and 16 (School-Based Issues) whose clinical caseloads included students diagnosed with ADHD participated in an anonymous, online survey to determine the relationship between various factors and SLPs' comfort level when working with students with ADHD.

Results

Correlations revealed feeling adequately trained predicted SLPs' comfort level in working with students with ADHD. SLPs who either received coursework that included content regarding ADHD in school or sought out professional development reported feeling adequately trained. Regression analyses revealed feeling adequately trained and having a reasonable caseload as significant predictors of SLPs' comfort level.

Conclusions

Not all SLPs were comfortable working with students with ADHD. Many sought courses to increase their level of comfort, and many did not feel adequately trained. Results suggest the need for SLPs to have more preparation about managing ADHD prior to beginning their professional clinical careers.
Optimal control theory and advanced optimality conditions for a diffuse interface model of tumor growth
Authors: Ebenbeck Matthias , Knopf Patrik
Published: September 2019

We investigate a distributed optimal control problem for a diffuse interface model for tumor growth. The model consists of a Cahn–Hilliard type equation for the phase field variable, a reaction diffusion equation for the nutrient concentration and a Brinkman type equation for the velocity field. These PDEs are endowed with homogeneous Neumann boundary conditions for the phase field variable, the chemical potential and the nutrient as well as a “no-friction” boundary condition for the velocity. The control represents a medication by cytotoxic drugs and enters the phase field equation. The aim is to minimize a cost functional of standard tracking type that is designed to track the phase field variable during the time evolution and at some fixed final time. We show that our model satisfies the basics for calculus of variations and we present first-order and second-order conditions for local optimality. Moreover, we present a globality condition for critical controls and we show that the optimal control is unique on small time intervals.
Study on Residual Stress Distribution of 7050 Aluminum Sheet with Groove after Laser Shock Peening
Authors: Du Yong , Ma Yu'e , Gou Lei , Guo Chao , Li Bo , LI Gang
Published: September 2019

In order to study the residual stress profile of 7050-T7451 aluminum sheet with groove after laser shock peening (LSP), the residual stress distribution was measured. It is shown that the residual stress decreases gradually from the center to the edge of groove; and then there is the minimum value at the edge of the groove bottom surface. By using ABAQUS software to establish three-dimensional finite element model for 7050 aluminum sheet with groove, and the load was applied by VDLOAD subroutine. The finite element analysis was performed and the analysis results were compared with the experimental measurements, in which the both the results agree with each other very well. And then the residual stress distribution of the sheet was analyzed after laser shock peening under different laser processing parameters. It is shown that the residual stress decreases firstly and then increases with the rise of laser power density from 0.84 GW/cm2 to 5.29 GW/cm2. And the residual stress obtains the minimum value -230 MPa at the laser power density of 3.06 GW/cm2. With the increasing of spot diameter from 4 mm to 6 mm, the residual stress increased from -214 MPa to -30 MPa. With the increasing of laser pulse width from 10 ns to 40 ns, the residual stress decreased from -21 MPa to -288 MPa; and the depth of the compressive residual stress increased too. For all simulations under different LSP parameters, the minimum surface residual stress achieved at the bottom surface of the groove as well.
Influence of Geometric Error of Rollers on Rotational Accuracy of Cylindrical Roller Bearings
Authors: Yu Yongjian , Chen Guoding , Li Jishun , Xue Yujun
Published: September 2019

As the rotation of roller bearings is carried out under geometrical constraint of the inner ring, outer ring and multiple rollers, the motion error of the bearing should also be resulted from geometric errors of bearing parts. Therefore, it is crucial to establish the relationship between geometric errors of bearing components and motion error of assembled bearing, which contributes to improve rotational accuracy of assembled bearing in the design and machining of the bearing. For this purpose, considering roundness error and dimension error of the inner raceway, the outer raceway and rollers, a prediction method for rotational accuracy of cylindrical roller bearings is proposed, and the correctness of the proposed prediction method is verified by experimental results. The influences of roller's geometric error distribution, roller's roundness error and the number of rollers on the runout value of inner ring are investigated. The results show that, the roller arrangement with different geometric errors has a significant impact on rotational accuracy of cylindrical roller bearings. The rotational accuracy could be improved remarkably when multiple rollers with different dimension error are distributed alternately according to the size error. Even-order roundness error of rollers has a significant effect on the rotational accuracy, and the decrease level depends on the orders of roundness errors of bearing parts and the number of rollers. But odd-order roundness error of rollers has almost no effect on the rotational accuracy. The rotational accuracy of assembled bearing would be significantly improved or decreased when even order harmonic of rollers and the number of rollers satisfy specific relationships. The greater the order of roundness error of the rollers, the more severe the influence of the roller number on rotational accuracy of assembled bearing. The rotational accuracy can not be always improved with the increase of the number of rollers.
Detailed mechanisms of hydrogen charging and hydrogen stress cracking of steel in liquid ammonia storage
Authors: Crolet J.-L.
Published: September 2019

When the unprecedented environmental cracking of steel in liquid ammonia was collectively studied, its undisputable “anodic character” was taken as the signature of astress corrosion crackingmechanism, which is effectively the case in aqueous corrosion. Conversely, when the metallurgical precautions proved to be the same as in sour service, this strongly suggested ahydrogen stress crackingmechanism. In aqueous corrosion, however, this can only occur by cathodic hydrogen charging at low potential, and for 50 years, this basic contradiction could never be overcome. Actually, it occurs that the liquid ammonia solvent (NH3) is 50% richer in hydrogen than the water solvent (OH2), so that hydrogen gas can also be produced by a partial oxidisation into ½ N2 + H2. This therefore induces a theoretical possibility of an “anodic” hydrogen charging, or more exactly a protonic cathodic reaction only running at high potential on passive iron in oxygen contaminated ammonia. And once the detrimental potential is achieved through appropriate combinations of oxygen and water traces, the charging process becomes an autonomous oxidation-reduction at the steel surface NH3 → ½ N2 + H2 + (H+ + e−)steel. In Part II (Jean-Louis Crolet,Matériaux & Techniques107, 402, 2019), this new assumption will be successfully confronted to all the factual data from both field and laboratory experience.
Influence de la distribution en taille (broyat de noyaux d’olive) sur les propriétés de la brique
Authors: Djadouf Samia , Chelouah Nasser , Tahakourt Abdelkader
Published: September 2019

Ce travail évalue l’effet de la granulométrie du broyat de noyaux d’olive (BNO) sur les propriétés de la brique de terre cuite. Les noyaux d’olive concassés sont tamisés pour séparer les différents diamètres (1,5, 1, 0,5 et 0,25 mm). Nous avons confectionné quatre séries d’échantillons contenant 5, 10, 15 et 20 % de BNO dans la masse d’argile pour les essais. Les matières premières argile et BNO ont été caractérisées aux moyens d’analyses chimique et minéralogique, analyse thermique gravimétrique TG-DTG. Les propriétés physico-mécanique et thermique des éprouvettes cuites à 1000 °C, telles que, la porosité, l’absorption d’eau, la résistance à la compression, et la conductivité thermique ont été évaluées. Cette étude présente des résultats intéressants pour augmenter le pouvoir d’isolation des briques. Nous avons œuvré sur l’optimisation du diamètre de l’ajout, en travaillant sur la réduction des ponts thermiques et la diminution des transferts de chaleur dans les cavités produites par la consumation du BNO. Nous avons constaté que pour des diamètres plus petits de l’ajout; la conductivité thermique est de moindre avec des résistances à la compression avérées.
Calcifying odontogenic cyst: a report of two clinical cases
Authors: Lagarde Xavier , Sturque Julie , Fenelon Mathilde , Marteau Jean Marie , Fricain Jean Christophe , Catros Sylvain
Published: September 2019

Introduction: Cystic maxillary lesions are common. In 1962, Gorlin described a rare cystic form termed the calcifying odontogenic cyst (COC) or Gorlin's cyst. Two cases of this form were treated at Bordeaux University Hospital. Observation: The first case was a 17-year-old patient with mandibular odontoma, which had developed over the previous 6 months. Excision was performed under local anesthesia, and the diagnosis of COC was made following pathological analysis. A 6-month follow-up was planned. The second case was a 62-year-old patient with a post-extraction mandibular lesion, which had been evolving for 1 year. Enucleation under local anesthesia led to the diagnosis of COC. No recurrence was observed after 5 years of follow-up. Discussion: COCs are rare lesions affecting mainly the anterior aspect of the mandible. COCs are usually discovered in unforeseen circumstances, and they can be observed as a clinically painless and well-defined oral deformation. Radiological examination often reveals radiolucent and uniloculated lesions, sometimes associated with radiopaque lesions. Pathological analyses are required for final diagnosis. Management is based on complete excision, more or less associated with marsupialization, and requires an annual clinical radiographic monitoring over the next 5 years. Conclusion: COC are rare lesions, usually asymptomatic, whose treatment is based on complete excision. Clinical and radiological follow-up is necessary until complete reossification is achieved.
Inclusions evolution during the LF refining process of 439 ultra-pure ferritic stainless steel
Authors: Chen Xingrun , Cheng Guoguang , Hou Yuyang , Li Jingyu
Published: September 2019

The morphology, composition, size, and number of inclusions in 439 ultra-pure ferritic stainless steel samples were analyzed using an automatic scanning electron microscope combined with an energy-dispersive X-ray spectrometer. In addition, the appropriate contents of titanium, aluminum, and calcium were analyzed through the coupling of thermodynamics calculation and experimental results. CaO-Al2O3-MgO inclusions existed in the 439 steel before Ti additions in the ladle furnace (LF) refining process. After Ti addition in the LF refining process, the inclusions were transformed into CaO-Al2O3-MgO-TiOx inclusions. The evolution of these inclusions was consistent with thermodynamic calculation, which indicated that when the Al, Ca, and Ti contents were within a reasonable range, Ca treatment could significantly modify the aluminate and spinel to form CaO-Al2O3-MgO liquid inclusions. In addition, the compositions of inclusions after the addition of titanium were mostly located in the Al2O3-TiOx stable phase. The collision of the CaO-Al2O3-MgO liquid inclusions and Al2O3-TiOx inclusions resulted in the modification of the CaO-Al2O3-MgO-TiOx inclusions. The compositions of most inclusions were located in the liquid zone. The control range of the aluminum, calcium, and titanium contents was obtained: logAl% ≥ 1.481logTi% − 0.7166, Ca% ≥ 34.926(Al%)3 − 3.3056(Al%)2 + 0.1112(Al%) − 0.0003.
Comparison of internal and external threads pitch diameter measurement by using conventional methods and CMM’s
Authors: Yüksel İ. Ahmet , Kılınç T. Oytun , Sönmez K. Berk , Ön Aktan Sinem
Published: September 2019

Threads are very frequent and critical connection methods of components to build final products as per desired technical requirements. As it is used for very wide numbers of applications and industries, tolerances and thread structure differ as per requirements of applied areas. After theoretical decision of threaded parts, one hard task is to manufacture this thread as required. Correct flank angle, pitch diameter, pitch, height, major/minor diameters shall be obtained to receive desired mechanical connection properties. So as a result of all importance of threaded connection, it is also important to control thread properties. In this study it is aimed to show that as a result of significant development on sensor and probing technology, Coordinate Measuring Machines (CMMs) are good alternatives of conventional methods by considering accuracy, time requirement, setup requirements, and ease of application. In order to evaluate competence of regular bridge type CMMs regarding simple pitch diameter measurement, results of pitch diameter from symmetric thread with 30º flank angles will be taken by 1D length measurement device and bridge type CMM to compare. Comparison of conventional methods and CMM’s result shows that CMMs also provide accurate and precise results and can be used for calibration of gages as an alternative method with a number of advantages which are shown by this study.
Investigation in optimisation of accuracy with non-contact systems by influencing variable processes
Authors: Matharu Ranveer S. , Sadler Wayne , Gashi Bekim V. , Toman Trevor
Published: September 2019

The use of 3D scanning systems is becoming increasingly popular and an essential tool for manufacturers for inspection and measurement. With such systems being utilised on the manufacturing shop floor due to their portability and ease of use, it is no doubt that such systems are designed to address a variety of users whom, with minimal training can operate the equipment. Due to continuing demands of high-quality products there is the need for manufacturers of 3D scanning systems to develop technologies that deliver fast and accurate information. However, one of the key challenges lies not in the training of people to use the equipment, but to develop engineers who can produce traceable, accurate and precise results with a declared statement of confidence quantifying the quality of the measurement. This statement of the quality of the output results relies on employing a set of workflow actions that involve planning, capture, processing and analysis, and finally output. This paper sets out to show how the results from a set of workflow actions from different categories of 3D scanning devices affects the quality of output.
Traceability Features of the Electric Power Unit in Ukraine
Authors: Velychko Oleh , Karpenko Stanislav
Published: September 2019

The paper describes some aspects concerning the realization of the electric power unit traceability in Ukraine in the CIPM MRA understanding through participation in Key and Supplementary Comparisons of national standards and in the ILAC MRA understanding through participation in inter-laboratory comparisons. The authors have demonstrated comparative analysis of EURAMET.EM-K5.1, COOMET.EM-S2, COOMET.EM-K5 comparisons results and practically realized the procedure for realisation traceability of the electric power unit in Ukraine.
Proficiency testing for calibration of multimeter
Authors: SUGLIANO Nathalie
Published: September 2019

In 2018 and 2019, CT2M organize an inter-laboratory comparison of multimeter calibration in which 27 Europeans laboratories participated. Among them were calibration laboratories (accredited or not) but also laboratories performing themselves the calibrations of their multimeter. The principle of this inter-laboratory comparison is to circulate a multimeter from one laboratory to another in order to compare the calibration results (including correction and calibration uncertainty). The processing of the results is carried out according to the ISO 13528 statistical principles and in compliance with the requirements of ISO 17043. A final report in 2019 will indicate to the participants all the results in anonymous way and the performance scores to evaluate the ability of laboratories to carry out this calibration. This article will present the organization of this inter-laboratory comparison as well as the results obtained.
The TiFOON Project – Time and Frequency Over Optical Networks
Authors: Kronjaeger Jochen
Published: September 2019

The unprecedented accuracy of modern optical clocks has spurred the development of matching frequency comparison techniques, with optical frequency transfer over fibre emerging as the method of choice. However, the generation and dissemination of the international reference time scale, as well as many applications outside metrology, require reliable and economically sustainable time transfer in addition to frequency transfer capabilities. To address these needs, a new EMPIR-funded project TiFOON – Time and Frequency Over Optical Networks - has been set up with the aim of advancing fibre-based frequency transfer capabilities in Europe towards a universal tool for time and frequency metrology and other demanding applications.
Risk calculations for conformity assessment in practice
Authors: Allard Alexandre , Fischer Nicolas , Smith Ian , Harris Peter , Pendrill Leslie
Published: September 2019

In 2012, the Joint Committee for Guides in Metrology (JCGM) published novel guidance on the consideration of measurement uncertainty for decision-making in conformity assessment (JCGM 106:2012). The two situations of making a wrong decision are considered: the risk of accepting a non-conforming item, denoted as the customer risk, and the risk of rejecting a conforming item, denoted as the producer risk. In 2017, the revision of ISO 17025 obliged calibration and testing laboratories to “document the decision rule employed, taking into account the level of risk (such as false accept and false reject and statistical assumptions) associated with the decision rule employed, and apply the decision rule” in the context of the decision made about the conformity of an item. However, JCGM 106:2012 can in some cases be perceived as quite difficult to apply for non-statisticians as it mainly relies on calculations involving probability distributions. In order to facilitate uptake of the methodology of JCGM 106:2012, EURAMET is funding the project EMPIR 17SIP05 “CASoft” (2018 – 2020), involving the National Measurement Institutes from France, Sweden and the UK. The objective is to make the methodology accessible to organisations involved in decision-making in conformity assessment: calibration and testing laboratories, industrialists and regulation authorities. Where the customer or producer are concerned, there are two kinds of risks arising from measurement uncertainty: specific risk which concerns the risk of an incorrect decision for a particular item and global risk which is the risk of an incorrect decision for any item chosen at random. Both kinds of risk may involve prior information, taken into account through a so-called prior probability distribution, introducing the concept of a Bayesian evaluation of the risks. If a calibration and testing laboratory performing the measurement has difficulty accessing prior information, it is likely that the industrialist in control of production processes will have some idea of the quality of the items produced. In this paper, the two problems of estimating the specific and global risks are addressed. The consideration of prior information is also discussed through a practical example as well as the use of software implementing the methodology, which will be made publically available at the end of the project.
Role of measurement uncertainty in conformity assessment
Authors: Puydarrieux Stéphane , Pou Jean Michel , Leblond Laurent , Fischer Nicolas , Allard Alexandre , Feinberg Max , El Guennouni Driss
Published: September 2019

Conformity assessment, focused on risks quantification, evolved from being binary to being probabilistic. In fact, new methods described by the standard ISO CEI guide 98-4 [1] and FD X 07-039 [2] show how measurement uncertainty is integrated in the conformity assessment (FD X 07-039 : “Role of measurement uncertainty in conformity assessment – implementation of NF ISO/IEC Guide 98-4 – illustration through industrial case studies”). In such a probabilistic framework, the conformity assessment relies on two quantities: the measurement with its related uncertainty and the measurand prior knowledge. Both quantities are combined statistically to determine measurand posterior knowledge, and to quantify a global or specific risks either for the producer or the consumer. The standard also defines how integrating those two quantities improves the reliability of decisions based on measurements. This work will first present a clarification of the probabilistic approach described by the FD X07-039. Then, the measurand prior knowledge use will be explained. Finally, future metrology applications caused by such an approach will be listed.
The influence of Gas Type on a Thermal Mass Flowmeter Calibration Results
Authors: ABBAS Oras , Mouchel Fabrice
Published: September 2019

The Thermal Mass Flowmeters (TMFMs) have been used for more than twenty years in the industry for various uses, including sweeping, gas injection, and welding. Their operational behaviors are still not well understood by operators. TMFMs, could be used with multiple process gases, and sometimes, highly toxic gases and they are generally calibrated with nitrogen or air. In the case of using a surrogate gas for calibration, a correction factor (k-factor) is required to estimate the flow of the process gas. Most of the time, these correction factors are indicated in the manufacturer’s instructions manual. In the field of metrology, k-factor plays a significant role in calibration results. Therefore, it is important to understand the influence of gas type used in calibration on the results if the process gas is employed or a surrogate gas with the recommended k-factor. The aim of this paper therefore is to discuss and evaluate the impact of using manufacturers k-factor in place of the actual process gas during calibration. The tests results presented within this article are considered concerning within the field of metrology.
Experimental and numerical investigations on the shape and roughness of cylindrical critical flow venturi nozzles (CFVN)
Authors: Lambert Marc Antoine , Maury Rémy , Valière Jean-Christophe , Foucault Eric , Lehnasch Guillaume
Published: September 2019

This paper describes a part of a research project aimed at reducing the uncertainty of the determination of the CFVN discharge coefficient. In the current state of the work, there are two parallel studies: an experimental and a numerical. Experiments have been carried out to determine the impact of roughness on the CD and to demonstrate the need for dimension parameters, such as diameter and roughness coefficient characterisation. Numerical simulations are used in the same CFVN geometry with a smooth surface to determine the main parameters which can influence the numerical prediction of the discharge coefficient and the flow behaviour. The results show that an increase of roughness may lead to a significant decrease of the discharge coefficient, particularly in the high Reynolds number range.
Methods for dynamic calibration and augmentation of digital acceleration MEMS sensors.
Authors: Seeger Benedikt , Bruns Thomas , Eichstädt Sascha
Published: September 2019

We present a method for data acquisition and calibration of digital accelerometers which is being developed within the EMPIR Met4FoF project based on STM32 microcontrollers. Unlike analog sensors, some MEMS sensors with digital interface generate the sample clock themselves. For a dynamic calibration the exact knowledge of the sample times is essential. Therefore, an interrupt controlled data acquisition based on hardware timers with absolute time stamping was implemented. These routines are generic and can be used both for sensors that perform the measurements automatically, or for sensors whose data acquisition is requested by a hardware or software interrupt. The synchronization of the hardware timer with the absolute time is done via GNS time services or another PPS time source. The data is transferred from the microcontroller via ethernet to a host PC, which is to provide an OPC-UA interface and thus enables simple integration of the sensor system into larger measuring systems, like existing calibration setups. In addition to the acquisition of raw data for sensor calibrations, the system consisting of microcontroller and driver on the host system is also intended to provide dynamic measurement uncertainties. In addition, information about the calibration and the status of the sensor should be available on the system. The calibration data should be stored inform of a signed xml file on the microcontroller. In addition to this static information, the system should also record dynamic information about the status of the sensor, such as operating time, exceeding of measuring ranges, min and max temperature during operation.
New optical power sensors using pyrolytic graphite
Authors: Silvestri Zaccaria , Pinot Patrick
Published: September 2019

A new method for measurements of laser power, using pyrolytic carbon (PyC) levitation as torsional magnetic spring, to detect the moment of force provided by radiation pressure of laser beam is currently developed at the LCM LNE-Cnam. This new power-meter could measure laser power in the range from 300 mW to 100 W with an objective to reach a relative uncertainty of about 1%. Relative to a first experimental setup, the new configuration presented in this paper has been improved taking the main disturbing sources into account. The traceability to SI units of the measurement provided by this new power-meter is presented and discussed.
Autonomous vehicles for remote sensing use – Opportunities and challenges for Drone
Authors: LAURONT Jean-Louis , GUILHOT Michel , HARNOIS Pascal , STRAHAN Gary
Published: September 2019

-Emergence of autonomous robotics and vehicles thanks to sensors, embedded processors and communication progress open new horizon for making remote sensing measurement without exposing human to unecessary risks. The collection of regular data in various environement (outdoor or indoor) allow more efficient predictive and preventive maintenance of assets that are difficult to access. Autonomous vehicle operating on ground, in the air or on water can shape a new future for science, industry and environnement. The optical and photonic industries offer now a wide range of compact sensor solutions using different wavelength not only to permit autoguidance of vehicles but also to complete the range of sensor already used for gathering various physical values with the advantage of non-contact. The application are numerous and encompass amongst other thermography, gas detection, hyperspectral imaging, security which can be extremely helpful for carrying day to day tasks for first responder, EHS officers, governmental regulatory organization, scientists…Routine checks can be thus envisaged that will save money by preventing or lessening risks or failure, better protecting environment and people, capitalizing on larger databases making use of AI. INNOVIDEA through its diverse industrial innovative partners will illustrate several example of use with drone (UAV/UAS/RPAS)
Determination of the coefficient of expansion of a carbon tube and its assembly for thermal compensation of metrological structures
Authors: EL ASMAI Salma , HENNEBELLE François , COOREVITS Thierry , FONTAINE Jean-François
Published: September 2019

Composite materials are increasingly used in 3D metrology devices. Their use is justified by their interesting mechanical properties including their low density and good rigidity but especially their low coefficient of thermal expansion. In fact, in order to improve production efficiency, companies nowadays integrate more and more control equipment directly in situ. These are then subject to thermal variations. The use of composite materials is an interesting approach. However, in some cases, the lack of knowledge of their coefficient of thermal expansion and their behavior might increase measurement uncertainties. The objective is to study the thermal behavior of a carbon tube alone and the same tube with aluminium fixing elements at its extremities, in order to determine the coefficients of expansion of the carbon alone and to quantify the influence of the fixation with aluminium elements. This experiment makes it possible to directly compensate the dimensional variations of the metrological structure depending on the temperature variations and thus to limit measurement uncertainties. The thermal expansion coefficients of the carbon tube and its assembly are determined by measuring relative variations in height with a ZERODUR® reference bar. The whole is positioned in a climatic chamber. *
Development of a Primary Dynamic Calibration Method for Pressure Sensors
Authors: Platte Thomas
Published: September 2019

An increasing research activity in the field of dynamic calibration of pressure transducers can be recognized at some national metrology institutes. As an example the EMPIR project “development of measurement and calibration techniques for dynamic pressures and temperatures” can be named. Despite that efforts, no national reference standard for dynamic pressure calibration is available up to now. This makes the measurement of high fluctuating pressure signals difficult and unprecise. These dynamic pressure signals appears in aerospace applications, blast test and almost every fluidic circuit which employs discontinuous discharge elements. To address that topic the authors developed a sine calibration apparatus to measure the frequency response of pressure transducers with sufficient amplitudes up to 1.2 MPa. Due to the construction of the pressure generator frequencies up to 10 kHz can be reached. Furthermore a calibration technique was developed to calculate the pressure inside a chamber primarily. The fundamental idea is to calculate the pressure based on the displacement of a piston in a pistonphone device. To do so the author had to analyses the thermodynamic conditions inside the fluid filled chamber. The paper shows that the fundamental approach was confirmed by measurements.
Improvement of INRiM static expansion system as vacuum primary standard between 10-4 Pa and 1000 Pa.
Authors: Astrua Milena , Mari Domenico , Pasqualin Stefano
Published: September 2019

The INRiM static expansion system has been recently modified in order to improve its performance and extend the working range down to 5.10-4 Pa. A new characterization of the system has been performed and a preliminary estimate of the uncertainty has been evaluated.
Improvement of dynamic pressure standard for calibration of dynamic pressure transducers
Authors: Durgut Yasin , Ganioglu Okhan , Aydemir Bulent , Turk Ahmet , Yilmaz Recep , Hamarat Abdullah , Bagci Eyup
Published: September 2019

In dynamic pressure measurement phenomena, dynamic pressure calibration of the measurement chain including a pressure sensor, signal conditioning amplifier and data acquisition part is required. A drop mass dynamic calibration machine which is used for the dynamic calibration in hydraulic media was designed and developed. This study presents a research study and measurement results on the dynamic calibration of pressure transducers by using the newly developed machine.
Micro-grinding temperature prediction considering the effects of crystallographic orientation
Authors: Zhao Man , Ji Xia , Liang Steven Y.
Published: September 2019

Tensile stress and thermal damage resulting from thermal loading will reduce the anti-fraying and anti-fatigue of workpieces, which is undesirable for micro-grinding, so it is imperative to control the rise of temperature. This investigation aims to propose a physical-based model to predict the temperature with the process parameters, wheel properties and material microstructure taken into account. In the calculation of heat generated in the micro-grinding zone, the triangular heat-flux distribution is adopted. The reported energy partition model is also utilized to calculate the heat converted into the workpiece. In addition, the Taylor factor model is used to estimate the effects of crystallographic orientation (CO) and its orientation distribution function (ODF) on the workpiece temperature by affecting the flow stress and grinding forces in micro-grinding. Finally, the physical model is verified by performing micro-grinding experiments using the orthogonal method. The result proves that the prediction matches well with the experimental values. Besides, the single-factorial experiments are conducted with the result showing that the model with the consideration of the variation of Taylor factor improves the accuracy of the temperature prediction.
Optimizing the buckling characteristics and weight of functionally graded circular plates using the multi-objective Pareto archived simulated annealing algorithm (PASA)
Authors: Farhatnia Fatemeh , Ali Eftekhari S. , Pakzad Alireza , Oveissi Soheil
Published: September 2019

In this study for the first time, weight and critical buckling load in two kinds of functionally graded (FG) circular plates, namely, aluminum–alumina of (Al/Al2O3) and aluminum–zirconia (Al/ZnO2), are optimized using multi-objective Pareto archived simulated annealing algorithm (PASA). Material properties are assumed to vary with the power law in terms of the volume fractions of the constituent in two forms of symmetric and asymmetric with respect to the middle surface. The plate is subjected to uniform radial load and is considered for two boundary conditions, namely, simply supported and clamped edges. Aim at obtaining the Pareto archive is to achieve simultaneously the maximum buckling and the minimum weight concerning with proposed constraints. The parameters include the radius, thickness and volume fraction that the certain range is intended individually. The constraints are presented in form of the ratio of thickness to radius in category of the thin plates as well as the critical buckling stress being in the elastic range. Proposed simulated annealing algorithm is coded in MATLAB to obtain optimal non-dominated solution.
Collaborative training of far infrared and visible models for human detection
Authors: Blondel Paul , Potelle Alex , Pégard Claude , Lozano Rogelio
Published: September 2019

This paper is about the collaborative training of a far infrared and a visible spectrum human detector; the idea is to use the strengths of one detector to fill the weaknesses of the other detector and vice versa. At first infrared and visible human detectors are pre-trained using initial training datasets. Then, the detectors are used to collect as many detections as possible. The validity of each detection is tested using a low-level criteria based on an objectness measure. New training data are generated in a coupled way based on these detections and thus reinforce both the infrared and the visible human detectors in the same time. In this paper, we showed that this semi-supervised approach can significantly improve the performance of the detectors. This approach is a good solution to generate infrared training data, this kind of data being rarely available in the community.