bluuebunny/crossref_metadata_2025 huggingface dataset:
Traffic accident analysis based on C4.5 algorithm in WEKA
Authors: Li Jiajia , He Jie , Liu Ziyang , Zhang Hao , Zhang Chen
Published: March 2019

At present, China is in a period of steady development of highways. At the same time, traffic safety issues are becoming increasingly serious. Data mining technology is an effective method for analysing traffic accidents. In-depth information mining of traffic accident data is conducive to accident prevention and traffic safety management. Based on the data of Wenli highway traffic accidents from 2006 to 2013, this study selected factors including time factor, linear factor and driver characteristics as research indicators, and established the decision tree using C4.5 algorithm in WEKA to explore the impact of various factors on the accident. According to the degree of contribution of each variable to the classification effect of the model, various modes affecting the type of the accident are obtained and the overall prediction accuracy is about 80%.
The method of forming probing signals of georadars on the basis of direct digital synthesizers for geodynamic monitoring
Authors: Grecheneva A V , Dorofeev N V , Kuzichkin O R , Surzhik D I , Romanov R V
Published: March 2019

The features of the formation of probing signals based on direct digital synthesizers for geodynamic monitoring of medias using georadar probing are considered in the article. The basic requirements for the formers of probing signals and the shortcomings of known technical solutions are shown. To eliminate them, as a former of probing signals of georadars was suggested to use direct digital synthesizers with improved spectral characteristics, achieved by introducing circuit of an automatic compensation of phase distortion with a control device in the form of a phase-locked loop. With this construction, the device contains a combination of autocompensation and filter methods of improving the spectral characteristics of the output signal of the synthesizer. To analyze the effectiveness of the proposed solutions, were obtained the necessary mathematical relationships describing the functioning of the device under research and implemented its schematic simulation, which showed the possibility of improving the spectral characteristics of the proposed former of probing signals by 10-15 dB.
Research on Wind Vibration Performance of Chinese Early Traditional Timber Structure –A case study of the Main hall of Tianning Temple
Authors: Chun Qing , Han Yidan , Jin Hui , Lin Yijie
Published: March 2019

In order to study the wind vibration performance of Chinese early traditional timber structure, the main hall of Tianning Temple in Jinhua of Zhejiang province was taken as an example. Firstly, based on the precise geometric information acquired by 3D laser scanning, the calculation model of the main hall was built by the finite element software of SAP2000, and its dynamic characteristics were analyzed. Then, the time history curves of fluctuating wind speed and fluctuating wind pressure based on AR model was generated by the software of MATLAB. The generated wind pressure was applied to the FEM model and analyzed. The results show that the top ten natural frequencies of this structureare among 3.617 Hz～18.672 Hz. The wind vibration response of this structure is mainly influenced by the top four natural modes. The wind vibration coefficients obtained by the time history analysis of wind pressure are 1.1~1.5 times of the wind vibration coefficients calculated according to the Chinese current load code. These results can provide a reference for analysis of wind vibration performance of Chinese early traditional timber structure.
Experimental study on the web crippling behaviour of pultruded GFRP channel sections using DIC
Authors: Zhang Li-Teng , Wu Chao
Published: March 2019

The use of pultruded glass fibre reinforced polymer has gained wide acceptance in civil engineering due to their excellent physical and mechanical characteristics, like low weight, high strength and durability in harsh environment. However, duo to the pultrusion process, pultruded GFRP sections are orthotropic and face a critical issuse of web crippling. This paper presents an experimental study on the web crippling behavior of pultruded GFRP channel sections under transverse bearing load. A total of twenty specimens were tested under two loading conditions, namely end-two-flanges (ETF) and interior-two-flanges (ITF). Five different bearing plates with length ranging from 20 mm to 200 mm were chosen to apply the transverse concentrated loading. It is observed taht all specimens initially cracked at the web-falnge junction. The experimental result also confirmed that both the web crippling capacities and stiffness increased with the increase of the bearing length. And the web crippling capacities are improved when the bearing plates are moved from the end to the middle of the specimen. The strain distributions at the web-flange junction obtained by DIC indicated that both the materials underneath the bearing plates and that near the bearing plates engaged in carrying the transverse bearing load.
Comparison of Bonding Performance Between Plywood and Laminated Veneer Lumber Induced by High Voltage Electrostatic Field.
Authors: He Qian , Zhan Tianyi , Zhang Haiyang , Ju Zehui , Hong Lu , Brosse Nicolas , Lu Xiaoning
Published: March 2019

High voltage electrostatic field (HVEF) was applied in order to improve wood surface characteristics, bonding and mechanical properties of wood composites. Masson pine (Pinus massoniana Lamp.) plywood and laminated veneer lumber (LVL) were selected in this study. Surface characteristics were conducted by the electron spin resonance (ESR) and X-ray photoelectron spectra (XPS). Bonding interphase and mechanical properties were investigated by fluorescence microscopy and vertical density profile (VDP), bonding strength, wood failure ratio, MOE and MOR. The results indicated that more increments were obtained in free radicals, O/C ratios and C2-C4 components. This is because electrons broke more wood chemical groups and new ions occurred among wood surface under HVEF. Significantly decreased PF adhesive penetration depth (PD) and increased density at bonding interphase was achieved in HVEF treated composites. More decrease of PD and increment of density were observed in plywood than that of LVL. This was attributed to cross linked wood fibers among bonding interphase in plywood. Mechanical properties of bonding strength, wood failure ratio, MOE and MOR were significantly increased under HVEF treatment both for two composites. Higher bonding strength, MOE and MOR were obtained in plywood and their increments were as 98.53%, 33.33%, 18.55% and 12.72%.
Study of SMA-dowelled timber connection reinforced by densified veneer wood under cyclic loading
Authors: Huang Haoyu , Chang Wen-Shao , Chen Ke
Published: March 2019

This study explores the dynamic behaviours of shape memory alloy (SMA)-dowelled timber connection with densified veneer wood (DVW) reinforcement, so as to provide resilience to the timber structure. The performance of the SMA bar under cyclic bending is firstly studied, and it is found that it has superior self-centring effect and large ductility compared with that of the steel. By testing the SMA-dowelled timber connections and the conventional steel-dowelled timber connections under cyclic loading at various displacement levels, it is shown that SMA can provide better self-centring effect and larger ductility to the connection. The DVW reinforcement can enhance the self-centring and improve the strength. However, the energy dissipation capacity of the SMA-dowelled timber connection is lower than that of the steel-dowelled connection because of the smaller hysteresis area of the SMA. In the further study, the effect of the temperature control on SMA should be investigated to improve the damping capacity of the SMA-dowelled timber connection.
A Statistics-Based Study on Wood Presentation of Modern Wood Building Facades
Authors: Xu Hongpeng , Li Jing , Li MengXuan , Wu Jianmei
Published: March 2019

Wood presentation of modern wood building facades relating to the expression of the essential characteristics of architecture, utilization efficiency of wood and acceptance of architectural image,etc. However, relevant studies are obviously insufficient. This paper makes a statistical analysis of outstanding wood structure space cases which be selected, tries to reveal the expression rule of major timber application variables of wood coverage, materials collocation, wood form and wood color under the limitation of the main influencing factors of building function, building form and building scale.The purpose of this study is to explore the wood presentation rule of modern wood building Facades under the influence of building factors.
Embedment Strength of Cross-Laminated Timber for Smooth Dowel-type Fasteners
Authors: Dong Weiqun , Li Qiao , Zhang Hao , Wang Zhiqiang , Zhou Jianhui , Gong Meng
Published: March 2019

Embedment strength is a significant property in the dowel type connection in timber structure, i.e. cross-laminated timber (CLT). The CLT design properties are different from those of sawn timber (ST) and glued-laminated timber (GLT) because of the orthogonal structure, which may particularly have influence on the design of connections. The layup feature, i.e. the thickness ratio of transverse layer (TRTL) was considered as an effective factor on CLT embedment strength in this study, except for other factors, i.e. wood density, smooth dowel diameter, and loading angle. Approximate 660 embedment tests were performed according to ASTM D5764 half-hole test method. A few of existing design models for CLT embedment strength were evaluated using experimental data. It was found that different factors had different effect tendency and each factor had statistically significant impact on CLT embedment strength. The embedment strength and failure modes of CLT were obviously different from those of GLT due to the existence of transverse layer in CLT. The existing design equations should be improved. Based on the test results, a new design equation was proposed which had better prediction.
Experimental Study on Uniaxial Compression of Bamboo Nodes Using 3D Scanning Technique
Authors: Meng Xinmiao , Sun Han , Cao Yuyang , Feng Peng
Published: March 2019

Bamboo is a kind of ecological building material for its physical and mechanical characteristics, such as fast growth, high yield, high strength, high toughness and good environmental performance. However, there are few studies on the influence of bamboo node structure about the mechanical properties of bamboo, and it is difficult to accurately determine the cross-section area of the bamboo node. In this paper, the three-dimensional scanner was combined with the reverse modeling technology to accurately obtain the cross-sectional area of the bamboo node. The bamboo node was subjected to axial compression test. Based on the experimental results, it was confirmed that the compressive strength of the bamboo node increased from the bottom to the top. The experimental results also showed that the difference in the degree of cracks has an effect on the bamboo break mode. Bamboo nodes with severe cracks and uneven distribution on the surface had the largest degree of expansion at the original deep cracks or the original surface through cracks. Bamboo nodes with slight cracks and even distribution or without cracks on the surface were uniformly expanding at the lower part when they were broken.
Experimental Study on Uniaxial Compression of Bamboo Poles with Different Reinforcements
Authors: Meng Xinmiao , Cao Yuyang , Sun Han , Feng Peng
Published: March 2019

The natural round bamboo is a kind of ecological building material with many excellent physical and mechanical characteristics, such as fast growth, high strength and good environmental performance. However, the natural round bamboos were barely used for its worse durability and easiness to crack compared other bamboo productions after secondary operation. In order to improve the safety and durability of the round bamboo structure, the axial compression test of the GFRP (glass fiber-reinforced polymer) and/or mortar reinforcing cracked bamboo was conducted. The 20 cm tall round bamboo column specimens were divided into five categories: the first without cracks and reinforcement, the second with cracks but without reinforcement, the third with cracks and full GFRP reinforcement, the forth with cracks and fulfil of cement motrar, and the last with cracks and reinforced using both GFRP and cement mortar. The bearing capacity and the failure modes were observed and studied. It was found that the composite reinforcement of GFRP and mortar could significantly increase the bearing capacity of the cracked round bamboos, and avoid brittle failure through improving the ductility of the specimens.
Two-dimensional Modelling of Thermal Responses of GFRP Profiles Exposed to ISO-834 Fire
Authors: Ding Teng , Wang Lu , Liu Weiqing
Published: March 2019

In the past three decades, one-dimensional (1-D) thermal model was usually used to estimate the thermal responses of glass fiber-reinforced polymer (GFRP) materials and structures. However, the temperature gradient and mechanical degradation of whole cross sections cannot be accurately evaluated. To address this issue, a two-dimensional (2-D) thermo-mechanical model was developed predict the thermal and mechanical responses of rectangular GFRP tubes subjected to one-side ISO-834 fire exposure in this paper. The 2-D governing heat transfer equations with thermal boundary conditions, discretized by alternating direction implicit (ADI) method, were solved by Gauss-Seidel iterative approach. Then the temperature-dependent mechanical responses were obtained by considering the elastic modulus degradation from glass transition and decomposition of resin. The temperatures of available experimental results can be reasonably predicted. This model can also be extended to simulate the thermo-mechanical responses of beams and columns subjected to multi-side fire loading, which may occur in real fire scenarios.
Shear Test of Variable Depth RC Beams with Inflection Point
Authors: Zheng Kaiqi , Kuwornu Michael , Liu Zhao
Published: March 2019

Variable depth continuous box girder bridges are widely used recently. However, the influence mechanism of the inflection point and variable depth on the shear behaviour of this type bridge has not been fully understood. In this paper, reinforced concrete (RC) beams with constant depth and variable depth were designed as constrained beams to create the inflection point. Firstly, a theoretical uncoupling theory for shear and flexural deformation of variable depth beam was derived. Then, the after cracking shear deformations and the ultimate failure loads were measured. Further, preliminary reveal of the influence mechanism of inflection point on the shear capacity was attempted. Finally, the development of after-cracking shear strain and the degradation of shear stiffness were studied. The formation of first critical diagonal cracks and yielding of stirrup are the turning points of shear stiffness. Increasing stirrup ratio provides more apparent enhancement for residual shear stiffness, which means more effective inhibition on shear deformation.
A study on image-processing based identification of aspect ratio of coarse aggregate
Authors: Li Tianhua , Bai Wenying , Zhang Kejia , Pan Zichao
Published: March 2019

The mesoscopic simulation of behaviours of cementitious materials under different conditions has become a hot topic in academic research, as it provides more details to the mechanism study and structural design. To conduct a mesoscopic simulation, the meso-scale model of cementitious materials must be built. To ensure the precision of the aggregate shape in the simulated meso-scale model, key shape parameters of real aggregates should be identified. In this paper, an image-processing based method is proposed to detect the aspect ratio of a polygonal aggregate. The procedure and used algorithms are demonstrated in detail. As an application, totally about 1000 coarse aggregates from the Xinjiang, China are selected to identify the aspect ratio. It is found that the aspect ratio of coarse aggregates is a random variable following the Generalized Extreme Value (GEV) distribution. The published data by using the X-ray technique is also adopted as a comparison, and the results are almost the same as each other, which indicates that the aggregate source does not have an obvious effect on the probabilistic characteristics of the aspect ratio.
Study on Vertical Dynamic Characteristics of Composite Sleeper Ballasted Track in Tunnels
Authors: ZHAO Zhenhang , SHEN Yuting , YAN Xue , SU Qiankun
Published: March 2019

In order to study the vertical dynamic characteristics of the composite sleeper ballasted track in tunnels, this paper establishes a dynamic model based on the finite element method, and compares the dynamic response of vehicle, wheel and rail systems, track systems and backfill layer with the type-III concrete sleeper. The research results show that the composite sleeper ballasted tracks’ acceleration of the car body and the wheel-rail force are smaller than that of the type-III sleeper. It can meet the safety of the train and passenger comfort. Because the composite sleeper has good elasticity, The rail displacement and acceleration, the sleeper displacement and acceleration of the composite sleeper are slightly larger than the type-III sleeper ballasted track, but the effect is not great. The composite sleeper has good elasticity and large damping, so that the acceleration of the track bed and the backfill layer is less than that of the type-III sleeper ballasted track. This shows that the composite sleeper has vibration damping characteristics for the track bed and the backfill layer.
Optimization method and application research of dewatering design for complicated foundation pits
Authors: Liu Zhengyong , Li Biao
Published: March 2019

The groundwater control system of complex deep foundation pit engineering is designed based on experience and analysis of items such as dewatering, anti-inrushing, water-recharging, etc. Three-dimensional numerical simulation methods are used to optimize the design. By repeatedly adjusting the design items and simulating the working system, a safer, more reasonable and economical design scheme can be confirmed by comparing the analysed results.
Effect of Wood Fiber on the Strength of Calcareous Sand Rapidly Seeped by Colloidal Silica
Authors: Jin Weifeng , Chen Rongzhong , Wang Xin , Cheng Zehai
Published: March 2019

Silica nano-particles are suspended in the colloidal silica and can be induced to gradually gel after the PH value changes. Thus colloidal silica can be utilized to rapidly seep through loose calcareous sand, and the silicon gel is gradually formed to bond sand particles. However, based on observation by scanning electron microscope(SEM), there are a lot of microcracks in the silica gel, which reduces the strength of the sand-gel composite. Therefore, in order to suppress crack growth, wood fibers are dispersed in the colloidal silica which still can seep through calcareous sand. 18 silicon-gel stabilized sand samples were prepared for tri-axial tests, where the concentration of colloidal silica is 20%, and wood fiber concentrations are 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, respectively. The results show that:(1) there exists an optimum ratio of wood fiber to colloidal silica, that is, as the concentration of wood fiber increases, the strength represented by the peak value of deviator stress rises first and then falls; (2) there are opposite trends between the two strength parameters, internal friction angle and cohesion, that is, when the wood fiber concentration is 0.04%, the cohesion reaches the maximum value and the internal friction angle reaches the minimum value; (3) The photos by SEM show that, there are wood fibers on the inner wall of the crack in the silica gel, which may reduce the extent of crack propagation and contribute to the strength of stabilized sand samples.
Acquisition method of asphalt pavement texture information based on the CPR Technology
Authors: Jiaying Chen , Binshuang Zheng , Xi Chen , Runmin Zhao , Xiaoming Huang
Published: March 2019

In order to obtain the asphalt pavement texture information in real time and accurately monitor the anti-skid performance of the road pavement, an automatic close range photogrammetry system (ACPR system) was proposed and built based on the circle arranged three cameras close range photogrammetry (CPR) technology to obtain the asphalt pavement surface texture. Automatic image acquisition and 3D reconstruction were achieved by the ACPR system. Sand patch method and laser scanning method (ZGScan) were used to collect the on-site comparison test of the asphalt pavement texture. Mean texture depth (MTD) and root mean square roughness (RSMR) were chosen as the statistical indicators of road surface texture. The results show that the texture data obtained by ACPR system has relatively high accuracy and efficiency, and the recognition accuracy is close to 0.02mm. The ACPR system improves the efficiency and accuracy of traditional close range photogrammetry and provides real-time and effective road surface anti-skid information for subsequent safety braking of autonomous vehicle.
Study on Resource Management for Prefabricated Concrete Building Based on BIM Technology
Authors: Ning XU , Guangbin Wang
Published: March 2019

A comparative analysis of resource management elements between PC (Prefabricated Concrete) structure and traditional cast-in-place structure was carried out firstly. Based on BIM (Building Information Modeling) technology, the resource management elements such as labour, materials and machinery for PC building were analyzed detailedly. It was shown that the dynamic and rational allocation of labour in the narrow work plan for PC building can be realized by the labour deployment method proposed in this paper; the adjustment time of the inclined bracing system for PC building can be reduced to a large extent by the this turnover method proposed in this paper; and the problem of arrangement and selection of tower crane for PC building can be solved by the analysis method of tower crane proposed in this paper.
Präkonzeptionelle Prävention
Authors: Trendelenburg Valérie , Korsten-Reck Ulrike , Dudenhausen Joachim W.
Published: March 2019

Das Thema präkonzeptionelle Übergewichtsprävention ist aktuell sowohl national
als auch international von hoher gesundheitspolitischer Bedeutung. So stellt die
präkonzeptionelle Beratung und Versorgung eine der 6 Empfehlungen des 2016
publizierten Aktionsplans „Ending Childhood Obesity (ECHO)“ der
Weltgesundheitsorganisation (WHO) dar, um Adipositas im Kindesalter zu vermeiden
und zu bekämpfen 1.
Richtig essen in der Stillzeit
Authors: Stasche Marlein
Published: March 2019

Eine der ersten und intensivsten Erfahrungen zwischen Mutter und Kind ist die
Stillzeit. Körperliche Nähe und Muttermilch sind das Beste für beide und in den
ersten 4–6 Monaten sollte idealerweise ausschließlich gestillt werden.
Synthesis of 2-Fluoroacetoacetic Acid and 4-Fluoro-3-hydroxy­butyric Acid
Authors: Mattingly Stephanie , Wuest Frank , Schirrmacher Ralf
Published: March 2019

The butyric acid scaffold is the base structure of several human metabolites that serve diverse and prominent biochemical roles including as oxidative sources of cellular energy and as substrates for biosynthesis. Derivatization of metabolites through incorporation of fluorine often alters bioactivity and can facilitate detection and analysis by nuclear magnetic resonance or positron emission tomography depending upon the fluorine isotope employed. We describe the synthesis of two new fluorinated butyric acids (and three related esters) that are derivatives of the metabolites acetoacetic acid and 3-hydroxybutyric acid. 4-Fluoro-3-hydroxybutyric acid is prepared from epoxy ester precursors via ring opening by triethylamine trihydrofluoride. 2-Fluoroacetoacetic acid is prepared by electrophilic fluorination of an acid-labile β-keto ester. The gradual pH-dependent decarboxylation of 2-fluoroacetoacetic acid is investigated by 19F NMR spectroscopy.
Effect of Treatment of Mild Gestational Diabetes on Long-Term Maternal Outcomes
Authors: Casey Brian M. , Rice Madeline Murguia , Landon Mark B. , Varner Michael W. , Reddy Uma M. , Wapner Ronald J. , Rouse Dwight J. , Biggio Joseph R. , Thorp John M. , Chien Edward K. , Saade George R. , Peaceman Alan M. , Blackwell Sean C. , Van Dorsten J. Peter ,   for the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units (MFMU) Network
Published: March 2019

Objective The main purpose of this article is to evaluate whether identification and treatment of women with mild gestational diabetes mellitus (GDM) during pregnancy affects subsequent maternal body mass index (BMI), anthropometry, metabolic syndrome, and risk of diabetes.

Study Design This is a follow-up study of women who participated in a randomized controlled treatment trial for mild GDM. Women were enrolled between 5 and 10 years after their index pregnancy. Participants underwent blood pressure, height, weight, and anthropometric measurements by trained nursing personnel using a standardized approach. A nurse-assisted questionnaire regarding screening and treatment of diabetes or hypercholesterolemia, diet, and physical activity was completed. Laboratory evaluation included fasting serum glucose, fasting insulin, oral glucose tolerance test, and a lipid panel. Subsequent diabetes, metabolic syndrome, obesity, and adiposity in those diagnosed with mild GDM and randomized to nutritional counseling and medical therapy (treated) were compared with those who underwent routine pregnancy management (untreated). Multivariable analyses were performed adjusting for race/ethnicity and years between randomization and follow-up visit.

Results Four-hundred fifty-seven women with mild GDM during the index pregnancy were included in this analysis (243 treated; 214 untreated) and evaluated at a median 7 years after their index pregnancy. Baseline and follow-up characteristics were similar between treatment groups. Frequency of diabetes (9.2 vs. 8.5%, p =0.80), metabolic syndrome (32.2 vs. 34.3%, p =0.63), as well as adjusted mean values of homeostasis model assessment for insulin resistance (2.5 vs. 2.3, p =0.11) and BMI (29.4 vs. 29.1 kg/m2, p =0.67) were also not different.

Conclusion Identification and treatment of women with mild GDM during pregnancy had no discernible impact on subsequent diabetes, metabolic syndrome, or obesity 7 years after delivery.
Efficient real-time estimation for DFIG—Performance and reliability enhancement of grid/micro-grid connected energy conversion systems
Authors: Djoudi Abdelhak , Bacha Seddik , Iman-Eini Hossein
Published: March 2019

This paper deals with an efficient real-time estimation (ERES) method for Doubly Fed Induction Generator (DFIG) parameters like resistances and inductances. The developed estimation technique is a sensorless method and is robust regarding measurement noises. Moreover, it estimates the rotating speed and the fluxes and their dynamics. The proposed estimation technique can easily serve to enhance the performances and the robustness of the related controllers. This technique can be employed for grid/micro-grid connected generation systems like DFIG-based Wind Energy Conversion Systems (WECSs) or other Energy Conversion Systems (ENCSs). The new approach is developed based on a DFIG state-space model and the recursive least squares algorithm. Simulations verify the viability of the proposed approach for a 1.5 MW DFIG-based WECS in the presence of measurement noises and parameter variations. A comparative study is also provided to show the superiority of the ERES-based adaptive sensorless sliding mode control approach compared to the classical one. It is observed that the motor drive ensures driving with a reduced number of sensors, lower tracking errors, and lower number of voltage fluctuations in the rotor.
Magnetostrictive vibrational power generator for battery-free IoT application
Authors: Ueno Toshiyuki
Published: March 2019

This study proposes a novel vibrational power generator based on magnetostrictive material (Fe–Ga alloy) for battery-free Internet of Things (IoT) applications. The device consists of a U-shaped magnetic frame with one leg forming a unimorph comprising a bonded Fe–Ga alloy plate and magnetic material, with a coil wound over the unimorph and a permanent magnet placed between the two legs of the frame. Via magnetically saturating the part of the frame at the point where the Fe–Ga plate is bonded, an electromotive force is generated in the coil by vibrations according to the change in the magnetic flux of the Fe–Ga alloy as generated by the inverse magnetostrictive effect. The device is simple in structure, highly robust, and affords an ease of assembling that is suitable for mass production. We also evaluate a prototype device (device weight of 4 g) using an Fe–Ga plate with dimensions of 4 × 0.5 × 16 mm. With a weight of 1.7 g attached to the device, an open-circuit voltage of 4 V at an oscillation frequency of 88.7 Hz and acceleration of 6.0 m/s2 yields an effective power of 2.0 mW. With a weight of 10.2 g, an effective power of 0.39 mW is generated at a frequency of 28.4 Hz and acceleration of 0.73 m/s2. After 100 million repeated oscillations at 420 Hz and 78.4 m/s2, the resonant frequency and voltage remain unchanged. The device performance is sufficient to replace the button cell used in wireless modules. Further, in order to examine the device feasibility, I investigate two applications related to short-distance (sending ON signals) and long-distance (sending data of temperature and vibration frequency) wireless sensors driven by the proposed device.
Production of nanocrystalline soft magnetic powders with high Bs by an improved rapid-cooling water-atomization process
Authors: Yoshida K. , Takahashi T. , Kuwata H.
Published: March 2019

A powder of Fe83.3Si4B8P4Cu0.7 composition with D50 of 4.2 μm was prepared by the modified water atomization system named “HPWA/YK”. The obtained powder had a mostly amorphous single phase. The powder was classified to several particle sizes and the difference of enthalpy between the as-quenched state and an after-primary-crystallization state was measured by DSC. As a result, it was found that the HPWA/YK system has better cooling capability than the conventional water atomizing method and the spinning water atomizing method. In conclusion, we consider that the HPWA/YK system contributes to mass production of nanocrystalline soft magnetic powders with high saturation magnetic flux density which require enormously rapid quenching.
Characterization of magnetic properties of nanocrystalline alloys under rotational magnetization
Authors: Chen Long , Ben Tong , Zhao Hanyu , Fang Chunhua , Wang Youhua
Published: March 2019

Due to lacking the measurement results of magnetic properties under rotational magnetization, the application of nanocrystalline alloys for high-power system energy conservation has been limited. In this paper, a high-frequency rotational magnetic property testing system is first introduced. Base on the testing system, the rotating loci of the vector magnetic flux density B and the vector magnetic field strength H are measured. Finally, the rotational core loss and anisotropy of nanocrystalline alloys are discussed and analyzed.
Behavior of Raman modes in InPBi alloys under hydrostatic pressure
Authors: Zheng Changcheng , Wang Xiaohu , Ning Jiqiang , Ding Kun , Sun Baoquan , Wang Shumin , Xu Shijie
Published: March 2019

Raman spectra of InPBi alloys with bismuth amount 0.3%-2.0% were measured under hydrostatic pressure in diamond anvil cell up to ∼4 GPa at room temperature. Two bismuth related Raman modes were identified and their evolutions under pressure were studied. The linear pressure coefficients of these two modes are determined to be 1.292 and 2.169 cm-1/GPa, respectively. The different behaviors of these two modes under pressure suggest that they may have distinct origins. InP related Raman modes were also investigated including two InP related modes caused by Bi doping.
Mapping of exciton–exciton annihilation in a molecular dimer via fifth-order femtosecond two-dimensional spectroscopy
Authors: Süß J. , Wehner J. , Dostál J. , Brixner T. , Engel V.
Published: March 2019

We present a theoretical study on exciton–exciton annihilation (EEA) in a molecular dimer. This process is monitored using a fifth-order coherent two-dimensional (2D) spectroscopy as was recently proposed by Dostál et al. [Nat. Commun. 9, 2466 (2018)]. Using an electronic three-level system for each monomer, we analyze the different paths which contribute to the 2D spectrum. The spectrum is determined by two entangled relaxation processes, namely, the EEA and the direct relaxation of higher lying excited states. It is shown that the change of the spectrum as a function of a pulse delay can be linked directly to the presence of the EEA process.
Engineered acoustic mismatch for anchor loss control in contour mode resonators
Authors: Lozzi Andrea , De Pastina Annalisa , Yen Ernest Ting-Ta , Villanueva Luis Guillermo
Published: March 2019

Improving the quality factor (Q) of electromechanical resonators is of paramount importance for different applications, ranging from RF filtering to sensing. In this paper, we present a modified fabrication process flow for contour mode resonators to simultaneously obtain the (i) Q insensitive to the Si undercut geometry and (ii) in-phase reflectors for anchor loss control and Q optimization. To assess the potential of the reflector, we vary its distance from the resonator's anchor. This results in a periodic trend of Q when the distance between the anchor and the reflector changes. Further confirmation of the trend is obtained via a finite element (FE) model. Interestingly, when in the FE model, the step between consecutive reflectors is decreased by a factor of 6× with respect to the experimental step, we observe a fast modulation of Q, superimposed onto that seen experimentally. The origin of this fast modulation is likely the coexistence of waves with different wavelengths traveling through the released region. Our results show that the profile of the region undergoing Si undercutting (released area) can be easily set by design. Furthermore, engineering the introduced acoustic mismatch provides unprecedented control of anchor loss.
Rutile GeO2: An ultrawide-band-gap semiconductor with ambipolar doping
Authors: Chae S. , Lee J. , Mengle K. A. , Heron J. T. , Kioupakis E.
Published: March 2019

Ultra-wide-band-gap (UWBG) semiconductors have tremendous potential to advance electronic devices as device performance improves superlinearly with the increasing gap. Ambipolar doping, however, has been a major challenge for UWBG materials as dopant ionization energy and charge compensation generally increase with the increasing bandgap and significantly limit the semiconductor devices that can currently be realized. Using hybrid density functional theory, we demonstrate rutile germanium oxide (r-GeO2) to be an alternative UWBG (4.68 eV) material that can be ambipolarly doped. We identify SbGe, AsGe, and FO as possible donors with low ionization energies and propose growth conditions to avoid charge compensation by deep acceptors such as VGe and NO. On the other hand, acceptors such as AlGe have relatively large ionization energies (0.45 eV) due to the formation of localized hole polarons and are likely to be passivated by VO, Gei, and self-interstitials. Yet, we find that the co-incorporation of AlGe with interstitial H can increase the solubility limit of Al and enable hole conduction in the impurity band. Our results show that r-GeO2 is a promising UWBG semiconductor that can overcome current doping challenges and enable the next generation of power electronics devices.
Dynamics of mutual harmonic synchronization between two coupled glow discharge plasma systems
Authors: Chaubey Neeraj , Mukherjee S. , Sen A.
Published: March 2019

The dynamics of harmonic synchronization between the anode glow oscillations of two mutually coupled glow discharge plasma systems are studied. The individual systems are operated in the regime where the frequencies of the anode glow oscillations increase linearly with an increase in the discharge voltage. In the experiments, the discharge voltage of one of the systems is kept fixed and that of the other increased progressively. A host of mutual synchronization phenomena is observed which includes a Devil's staircase progression of harmonic synchronization and frequency pulling and chaotic states. A systematic delineation of these experimental observations is presented, and some theoretical understanding is provided by the numerical simulation results of two coupled Van der Pol type equations.
Electronic properties of monoclinic (InxGa1-x)2O3 alloys by first-principle
Authors: Liu Xiaoli , Tan Chee-Keong
Published: March 2019

We report on the electronic properties of β-(InxGa1-x)2O3 alloys with different In-content up to 18.75% using density functional theory (DFT) calculations. The effect of In-content on the band structures as well as the crystal structures of β-(InxGa1-x)2O3 alloys is presented and discussed. Our analysis shows that β-(InxGa1-x)2O3 alloys exhibits indirect gap property, with the band gap reducing from 4.817 eV to 4.422 eV when the In-content increases up to 18.75%. The bandgap energy corresponds to the wavelength region extending from 255 to 280 nm, which implies the possibility for β-(InxGa1-x)2O3 alloys to be applied in the deep UV photodetectors. The electron and heavy hole effective masses are also obtained for the first time based on the band edge dispersions of the β-(InxGa1-x)2O3 materials. Additionally, the effect of band parameters on the impact ionization processes using β-(InxGa1-x)2O3 materials are analyzed. Our new insight regarding the electronic properties indicate the potential of β-(InxGa1-x)2O3 alloys in deep ultraviolet photodetector applications.
Electrocyclic Ring-Opening of 6,6-Dichlorobicyclo[3.1.0]-hexanes and Trapping of the Resulting π-Allyl Cations by C-1 Tethered Hydroxyamine Derivatives: Formation of 2-Oxa-1-azaspiro[4.5]decan-3-ones
Authors: Mikusek Jiri , Ward Jas S. , Banwell Martin G.
Published: March 2019

The C-1 substituted 6,6-dichlorobicyclo[3.1.0]hexanes 1a–c have been prepared and shown to undergo electrocyclic ring-opening to give the corresponding π-allyl cations 2 that cyclise to afford the spirocyclic products 3b–d, each of which has been subjected to single-crystal X-ray analysis.
Estimating average single-neuron visual receptive field sizes by fMRI
Authors: Keliris Georgios A. , Li Qinglin , Papanikolaou Amalia , Logothetis Nikos K. , Smirnakis Stelios M.
Published: March 2019

The noninvasive estimation of neuronal receptive field (RF) properties in vivo allows a detailed understanding of brain organization as well as its plasticity by longitudinal following of potential changes. Visual RFs measured invasively by electrophysiology in animal models have traditionally provided a great extent of our current knowledge about the visual brain and its disorders. Voxel-based estimates of population RF (pRF) by functional magnetic resonance imaging (fMRI) in humans revolutionized the field and have been used extensively in numerous studies. However, current methods cannot estimate single-neuron RF sizes as they reflect large populations of neurons with individual RF scatter. Here, we introduce an approach to estimate RF size using spatial frequency selectivity to checkerboard patterns. This method allowed us to obtain noninvasive, average single-neuron RF estimates over a large portion of human early visual cortex. These estimates were significantly smaller compared with prior pRF methods. Furthermore, fMRI and electrophysiology experiments in nonhuman primates demonstrated an exceptionally good match, validating the approach.
EZH1/2 function mostly within canonical PRC2 and exhibit proliferation-dependent redundancy that shapes mutational signatures in cancer
Authors: Wassef Michel , Luscan Armelle , Aflaki Setareh , Zielinski Dina , Jansen Pascal W. T. C. , Baymaz H. Irem , Battistella Aude , Kersouani Carole , Servant Nicolas , Wallace Margaret R. , Romero Pierre , Kosmider Olivier , Just Pierre-Alexandre , Hivelin Mikaël , Jacques Sébastien , Vincent-Salomon Anne , Vermeulen Michiel , Vidaud Michel , Pasmant Eric , Margueron Raphaël
Published: March 2019

Genetic mutations affecting chromatin modifiers are widespread in cancers. In malignant peripheral nerve sheath tumors (MPNSTs), Polycomb repressive complex 2 (PRC2), which plays a crucial role in gene silencing, is inactivated through recurrent mutations in core subunits embryonic ectoderm development (EED) and suppressor of zeste 12 homolog (SUZ12), but mutations in PRC2’s main catalytic subunit enhancer of zeste homolog 2 (EZH2) have never been found. This is in contrast to myeloid and lymphoid malignancies, which harbor frequent loss-of-function mutations in EZH2. Here, we investigated whether the absence of EZH2 mutations in MPNST is due to a PRC2-independent (i.e., noncanonical) function of the enzyme or to redundancy with EZH1. We show that, in the absence of SUZ12, EZH2 remains bound to EED but loses its interaction with all other core and accessory PRC2 subunits. Through genetic and pharmacological analyses, we unambiguously establish that EZH2 is functionally inert in this context, thereby excluding a PRC2-independent function. Instead, we show that EZH1 and EZH2 are functionally redundant in the slowly proliferating MPNST precursors. We provide evidence that the compensatory function of EZH1 is alleviated upon higher proliferation. This work reveals how context-dependent redundancies can shape tumor-type specific mutation patterns in chromatin regulators.
Reaction intermediates during operando electrocatalysis identified from full solvent quantum mechanics molecular dynamics
Authors: Cheng Tao , Fortunelli Alessandro , Goddard William A.
Published: March 2019

Significance

The gap preventing a direct comparison between experiment and atomic simulation still exists due to the unrealistic consideration of the operando experimental condition in commonly used quantum mechanics (QM). In this work, we advanced the QM-based simulation of the electrode–electrolyte interface with explicit consideration of solvent and applied voltage to produce reactive trajectories as input for a two-phase thermodynamics model in generating vibrational density of states that can be directly compared with the reported experimental spectroscopy. After resolving the signals, we successfully distinguished the reactive intermediates in a carbon dioxide reduction reaction, which provides an atomic-scale understanding of this important reaction.
Diverse fate of ubiquitin chain moieties: The proximal is degraded with the target, and the distal protects the proximal from removal and recycles
Authors: Sun Hao , Mali Sachitanand M. , Singh Sumeet K. , Meledin Roman , Brik Ashraf , Kwon Yong Tae , Kravtsova-Ivantsiv Yelena , Bercovich Beatrice , Ciechanover Aaron
Published: March 2019

Significance

The canonical targeting signal for degrading proteins by the ubiquitin (Ub) system—a chain composed of multiple Ub moieties—has remained a mystery. The structure of the proteasome, the enzyme that recognizes the signal and degrades the target substrate cannot explain why such a long chain is needed. To better understand this problem, we synthesized α-globin to which chains with different number of Ubs were attached. In long adducts, the proximal Ub remains on the substrate, likely securing its attachment to the proteasome, and is degraded with it. The distal Ub protects the proximal from removal by deubiquitinating enzymes and is then removed and recycled. In short adducts, the Ub moieties are rapidly removed, and the substrate remains stable.
Genomic plasticity associated with antimicrobial resistance in
Vibrio cholerae
Authors: Verma Jyoti , Bag Satyabrata , Saha Bipasa , Kumar Pawan , Ghosh Tarini Shankar , Dayal Mayanka , Senapati Tarosi , Mehra Seema , Dey Prasanta , Desigamani Anbumani , Kumar Dhirendra , Rana Preety , Kumar Bhoj , Maiti Tushar K. , Sharma Naresh C. , Bhadra Rupak K. , Mutreja Ankur , Nair G. Balakrish , Ramamurthy Thandavarayan , Das Bhabatosh
Published: March 2019

The Bay of Bengal is known as the epicenter for seeding several devastating cholera outbreaks across the globe.
Vibrio cholerae
, the etiological agent of cholera, has extraordinary competency to acquire exogenous DNA by horizontal gene transfer (HGT) and adapt them into its genome for structuring metabolic processes, developing drug resistance, and colonizing the human intestine. Antimicrobial resistance (AMR) in
V. cholerae
has become a global concern. However, little is known about the identity of the resistance traits, source of AMR genes, acquisition process, and stability of the genetic elements linked with resistance genes in
V. cholerae
. Here we present details of AMR profiles of 443
V. cholerae
strains isolated from the stool samples of diarrheal patients from two regions of India. We sequenced the whole genome of multidrug-resistant (MDR) and extensively drug-resistant (XDR)
V. cholerae
to identify AMR genes and genomic elements that harbor the resistance traits. Our genomic findings were further confirmed by proteome analysis. We also engineered the genome of
V. cholerae
to monitor the importance of the autonomously replicating plasmid and core genome in the resistance profile. Our findings provided insights into the genomes of recent cholera isolates and identified several acquired traits including plasmids, transposons, integrative conjugative elements (ICEs), pathogenicity islands (PIs), prophages, and gene cassettes that confer fitness to the pathogen. The knowledge generated from this study would help in better understanding of
V. cholerae
evolution and management of cholera disease by providing clinical guidance on preferred treatment regimens.
A corpus for signed language interpreting research
Authors: Wehrmeyer Ella
Published: March 2019

Because of the visual nature of signed language, the compilation of a signed language interpreting corpus along
the lines of spoken-language interpreting corpora has been viewed as extremely challenging, if not impossible. This study offers a
unique contribution in the construction of a lemmatized, annotated text-based corpus of signed language media interpretations,
which allows analysis of interesting features using readily-available concordance software. In this article, characteristics of
original (not interpreted) signed language corpora are explored in terms of metadata conventions, transcription and annotation, in
order to provide a framework for an interpreting corpus. Within this framework, the decisions and steps taken in the construction
of the interpreting corpus are discussed and explained.