bluuebunny/crossref_metadata_2025 huggingface dataset:
Graduate Student Difficulties on Electrostatics Topics -- Conductors and Insulators
Authors: Liu Qiaoyi
Published: April 2020

A lack of conceptual understanding of electrostatics principles, especially in the context of conductors and insulators, has been observed among a large number of introductory physics students as well as upper-level physics students. This work aims to explore graduate students’ misconceptions on these topics, particularly on how charges are distributed on conductors and insulators in various scenarios. Four first-year physics graduate students were selected to participate in think aloud interviews, where they were given a set of questions related to basic concepts of conductors and insulators, and asked to explain their thought processes as detailed as possible. The result of the four interviews are categorized by the test questions, which discusses the misconceptions that were demonstrated throughout the interviews, along with the interviewees’ reasoning behind these misconceptions. Despite that the interviewees have taken the introductory and advanced electricity and magnetism courses, a number of misconceptions still prevail in their conceptual understanding related to conductors and insulators. One possible explanation is the discontinuity between their knowledge of mathematical formulation and physical understanding of the concept, thus it is recommended that instructors should enforce students to review the advanced theory in the context of physical situations.
Influence of the Reform of College Entrance Examination on High School Physics Curriculum in Shanghai
Authors: Chen Yunlin , Zhu Guangtian
Published: April 2020

A new round of the reform of college entrance examination is in progress in China, which would inevitably influence high school curriculum, especially physics. According to our statistics, the proportion of students choosing physics as a selective subject decreased significantly after the reform of college entrance examination was carried out. We conducted a study in Shanghai, one of the pilot areas of the reform, to investigate the impact of the new reform policy of college entrance examination on high school physics curriculum with interviews and FCI tests, thus to provide references for the future reform. We found that compared with the conditions before the reform, the high school students from Shanghai learned less about physics and physics teachers has less time to teach and communicate with students. What is more, college freshmen from Shanghai fell behind those who came from other areas in FCI performance before and even after a term of formal instruction.
The dilemma and the improvement path of the proposition situation of science in Chinese college entrance examination
Authors: Gong Wenhui , Xing Hongjun
Published: April 2020

As the reform of the examination enrollment system and the examination content in China evolve, although we have witnessed some progress in the quality of science college entrance examination proposition, some challenges and problems persist, mainly in: inadequate diversity of situation, insufficient presentation of the situation and contempt for the scientific nature of situation. In view of the above issues in the compilation of proposition situation, the following improvements are proposed: select situation scientifically, present situation effectively, and explore whether the situation follows the nature of science.
Konsensus Pendidikan Islam di Nusantara (Studi Integrasi IMTAQ dan IPTEK dalam Pendidikan Islam)
Authors: Rachman Lutfi
Published: April 2020

Ajaran agama Islam yang lurus dan sarat  akan nilai- nilai keimanan serta moral, merupakan jaminan satu- satunya sekaligus benteng yang kokoh untuk keselamatan negara dan kebahagiaan manusia. Dimana di dalamnya terdapat pendidikan yang berlandaskan pada Ketuhanan yang mengajarkan pada keadilan dan menuju pada kebenaran serta membawa kita pada jalan yang lurus dan diridhai Allah SWT. Pendidikan dalam Islam merupakan  sebuah   rangkaian   proses pemberdayaan manusia menuju taklif (kedewasaan),   baik  secara  akal, mental maupun  moral, untuk  menjalankan  fungsi  kemanusiaan  yang diemban sebagai  seorang  hamba dihadapan Khaliqnya dan  sebagai "pemelihara" (khalifah) di bumi. Maka sebuah lembaga pendidikan Islam akan dapat diterima dan berkembang dengan baik serta mampu memberikan andil dalam mencerdaskan kehidupan berbangsa dan bernegara jika menghadirkan sebuah masa depan pendidikan Islam yang menjajikan
Analisis Dampak Motivasi Pengguna Media Sosial Terhadap Perubahan Perilaku
Authors: Raharjo Novianto Puji
Published: April 2020

Pengaruh motivasi pengguna media sosial terhadap perubahan perilaku Kehadiran media sosial yang ada saat ini memiliki hal tersendiri dalam kehidupan bermasyarakat. Dengan media sosial membuat dunia menjadi sangat sempit, itu karena kita membiarkan media sosial berkomunikasi dengan siapapun, dimanapun terhubung ke jaringan global Internet. Tidak hanya memudahkan proses komunikasi, namun keberadaan media sosial pada kondisi sekarang memberikan kemudahan selain sekedar berkomunikasi, hal yang terlihat saat ini adalah penggunaan media sosial sebagai alat penyederhanaan proses bisnis lintas batas lebih mudah. Atau juga bisa digunakan untuk melakukan propaganda tertentu media sosial. Jadi jika media sosial yang digunakan akan menjadi pisau bermata dua, sementara motivasinya untuk hal positif itu akan bagus, tapi kalau itu negatif maka hasilnya akan merugikan kehidupan di masyarakat.
Analisis Keputusan Pembelian Secara Online Pada Situs Toserba Pesantren.blogspot.com
Authors: Rofiuddin Mohammad
Published: April 2020

Toserbapesantren.blogspot.com merupakan salah satu blog/ website yang menjual alat musik tradisional Islami. Meskipun usia blog/website tersebut baru setahun lebih beberapa bulan, berdasarkan hasil wawancara kepada pemilik usaha omset yang dihasilkan mampu tembus di angka rata-rata 40 sampai dengan 70 Jt/bulan. Namun menurut data penjualan 5 bulan terakhir omset menurun cukup tinggi. Dalam penelitian ini bertujuan untuk mengetahui dan menganalisis :  1). Untuk analisis bagaimana dan seberapa besar pengaruh kepercayaan terhadap keputusan pembelian secara online, 2). Untuk analisis bagaimana dan seberapa besar pengaruh kemudahan terhadap keputusan pembelian secara online, 3). Untuk analisis bagaimana dan seberapa besar pengaruh kualitas informasi terhadap keputusan pembelian secara online. Sampel dalam penelitian ini adalah konsumen toko online Toserba Pesantren yang berjumlah 41 orang responden. Teknik pengambilan sampel yang digunakan dalam penelitian ini adalah non probability sampling. Teknik analisis data pada penelitian ini menggunakan Partial Least Square (PLS) dengan bantuan software Smart PLS 2.0 M3. Hasil penelitian Menyimpulkan bahwa (1) Kepercayaan memberi kontribusi untuk meningkatkan Keputusan Pembelian. (2) Kemudahan memberi kontribusi untuk meningkatkan  Keputusan Pembelian. (3) Kualitas Informasi tidak memberi kontribusi terhadap Keputusan Pembelian
ANDROCENTRISMO, A CONSTRUÇÃO DA DOMINAÇÃO CULTURAL MASCULINA
Authors: Ribeiro Soares Nascimento Dulcilene
Published: April 2020

Os discursos acadêmicos atualmente estão deveras voltados no sentido da desconstrução e superação dos preconceitos e  iscriminações produzidos ao longo da história pela sociedade .Em meio a tantos temas que pulsam pela revisão histórica está o  ndrocentrismo em toda sua extensão e alcance na sociedade pressionado pelo crescente debate em torno da temática dos gêneros e principalmente no sentido de conscientizar as gerações vindouras para a erradicação dos “centrismos” que dividem e desagregam os  alores humanos.
Progressive Visual Field Loss Associated With Optic Disc Drusen Over 25 Years
Authors: Emfietzoglou Ioannis , Grigoropoulos Vlassis , Vergados Ioannis , Nikolaidis Pandelis , Halkiadakis Ioannis , Theodossiadis George P. , Theodossiadis Panagiotis
Published: April 2020

The authors describe a case with optic nerve head drusen and normal intraocular pressure that was followed up for 25 years. The patient had kinetic perimetry annually until 1997 and static automated perimetry thereafter. From 2002 on, optical coherence tomography scans were also performed but did not permit accurate nerve fiber layer thickness measurement due to peripapillary extension of the optic nerve head drusen. Comparison of visual fields over 25 years reveal a gradual deterioration and demonstrate the value of this diagnostic tool in the study of the disease, especially in cases where nerve fiber layer loss cannot be precisely assessed by optical coherence tomography.
Genetic Predictors of Knee Pain in Persons With Mild to Moderate Osteoarthritis
Authors: Schutte Debra L. , Mukhopadhyay N. , Holwerda Teri , Sluka Kathleen , Rakel Barbara , Govil Manika
Published: April 2020

The purpose of this study was to examine genetic variability and knee pain in persons with osteoarthritis (OA). Seventy-five participants with medial compartment knee OA were recruited from a large Midwestern tertiary care center. Participants exhibited a mean age of 56.3 years; females comprised 61% of the sample. Measures of pain included subjective pain intensity at rest and with movement, cutaneous mechanical sensation and pain testing, heat pain threshold, and pressure pain threshold. Seventy-four participants were genotyped for 25 genetic variants across 15 candidate genes for central or peripheral pain pathways. Analysis suggests a role for four genes (
EDNRA
,
COMT
,
BDRKB1
, and
IL1B
) in several components of pain in persons with knee OA. The results from this study will help guide the development and evaluation of tailored strategies to decrease pain, improve function, and prevent the development of new chronic pain syndromes in older adults experiencing OA. [
Research in Gerontological Nursing, 13
(4), 191–202.]
Internet Programming to Reduce Loneliness and Social Isolation in Aging
Authors: Mullins Lindsay B. , Skemp Lisa , Reed David , Emerson Myra
Published: April 2020

Loneliness and social isolation in older adults carry mortality risks similar to cigarette smoking. The study aim was to use a Culturally Informed Healthy Aging (CIHA) assessment process in Housing and Urban Development (HUD) communities of older adults (
N
= 262). Through the CIHA assessment process, older adults identified pertinent health problems and the study team developed a health intervention, an Internet Information Station (IIS). The IIS pilot study included computer lesson participation (
n
= 261), written feedback (
n
= 42), and the revised University of California, Los Angeles (R-UCLA) Loneliness Scale (
n
= 11). Increased confidence with technology and connectedness were reported, and a significant difference in “There is no one I can turn to” was observed (IIS compared to non-IIS). The IIS remains an active site for interaction 1-year post intervention. These pilot results supplement the research on older adult engagement in problem identification, intervention design, and outcomes measurement.

Target:

Older adults living in HUD communities.

Intervention Description:

Through CIHA assessment, health problems were identified, and the IIS was developed and implemented.

Mechanisms of Action:

Lessons were developed (e.g., computer basics, connecting with technology, open forum) and evaluated. Pre and post lesson, the R-UCLA Loneliness Scale measured social isolation and loneliness.

Outcomes:

Older adults were engaged in problem identification, program development, and implementation. Feelings of connectedness improved; however, program evaluation with the R-UCLA scale was difficult to obtain.

[
Research in Gerontological Nursing, 13
(5), 233–242.]
Nanostructural Characterization of Nitrogen-Doped Graphene/ Titanium Dioxide (B)/ Silicon Composite Prepared by Dispersion Method
Authors: Yodying Waewwow , Autthawong Thanapat , Chimupala Yothin , Sarakonsri Thapanee
Published: April 2020

In this study, nitrogen-doped graphene (NrGO)/ titanium dioxide (B) (TiO2(B))/ silicon composites were synthesized by dispersion method. Weight ratios of NrGO:TiO2(B):Si were varied as 9:1:0, 8:2:0, 7:1:2 and 6:2:2. NrGO was prepared from graphite by the Modified Hummers method, followed by heat treatment under nitrogen atmosphere and N-added by annealing with melamine. TiO2(B) was prepared by hydrothermal method and its phase was confirmed by X-Ray powder diffraction pattern (XRD), transmission electron microscopy (TEM) and electron diffraction pattern. Silicon was synthesized from bamboo leaves by combustion followed by magnesiothermic reduction process. The results from XRD could confirm components of the composites and the unchanged phase of TiO2(B). From scanning electron microscopy (SEM) images of the composites, together with energy dispersive spectroscopy (EDS) data, silicon particles were distributed on the surface of NrGO, and TiO2(B) nanorods which are between 0.5-5 µm in length were distributed on the surface and spaces between layers of NrGO, and NrGO/TiO2 8:2 had the most thoroughly distribution of particles.
Common dermatological conditions in the HIV patient
Authors: Motswaledi H. M.
Published: April 2020

The introduction of antiretroviral medication has changed the epidemiology, morbidity and mortality of HIV disease. Nevertheless, cutaneous disorders due to HIV infection remain a major problem in HIV-infected patients. These disorders are mainly infections, inflammatory and neoplastic in origin. Some of these disorders occur at normal CD4 cell counts, while others occur typically at low CD4 cell counts. Clinicians should be aware of various presentations of these disorders and their treatment as they can impact negatively on patient’s quality of life
Smoking and Vaping: is there a difference?
Authors: Moutlana H. J.
Published: April 2020

No abstract available.
An Efficient Path Planning Methodology Based on the Starting Region Selection
Authors: Chen Xin , Qin Zhaobo , Fan Jingjing , Zhou Huajian , Chen Liang
Published: April 2020

Automated parking is an efficient way to solve parking difficulties and path planning is of great concern for parking maneuvers [1]. Meanwhile, the starting region of path planning greatly affects the parking process and efficiency. The present research of the starting region are mostly determined based on a single algorithm, which limits the flexibility and efficiency of planning feasible paths. This paper, taking parallel parking and vertical parking for example, proposes a method to calculate the starting region and select the most suitable path planning algorithm for parking, which can improve the parking efficiency and reduce the complexity. The collision situations of each path planning algorithm are analyzed under collision-free conditions based on parallel and vertical parking. The starting region for each algorithm can then be calculated under collision-free conditions. After that, applicable starting regions for parking can be obtained, and each of those regions corresponds to a parking path planning algorithm. However, there always exists overlapped starting regions, which can be applied to multiple parking path planning algorithms. In order to select the most suitable algorithm to plan the parking path, the priority order of algorithms is decided based on the preference criterion function. The collision-free parking path can be generated following the priority order. Based on the modified B-spline curves, a continuous-curvature path is presented. The simulation results based on MATLAB/Simulink and PreScan show that the methodology can smoothly judge the feasibility of automated parking in vehicle’s current position and plan the most suitable parking path. The proposed methodology can calculate the starting region of automated parking rapidly and plan more efficient parking path compared with other methods.
Guidelines for SUV Bodywork Design Focused on Aerodynamic Drag Reduction Using the Generic AeroSUV Model
Authors: Barrera David , Guzman Arturo
Published: April 2020

SUV Aerodynamics has received increased attention as the stake this segments holds in the automotive market keeps growing year after year, as well as its direct impact on fuel economy. Understanding the key physics in order to accomplish both fuel efficient and aesthetic products is paramount, which indeed gave origin to a major initiative to foster collaborative aerodynamic research across academia and industry, the so-called DrivAer model. In addition to this sedan-based model, a new dedicated SUV generic model, called AeroSUV [1], has been introduced in 2019, also intended to provide a common framework for aerodynamic research for both experimental work and numerical simulation validation. The present paper provides an area of common ground for SUV bodywork design focused on aerodynamic drag reduction by investigating both Estate and Fast back configurations of the generic AeroSUV model. Modified bodywork geometries focused at the rear end as well as spoiler angles, are evaluated using OpenFOAM Delayed Detached Eddy Simulations (DDES) utilising a Design for Six Sigma (DFSS) approach, such that not only a sensitivity study of drag response is yielded, but a ranking in terms of the potential for drag savings in certain areas of the car, is produced.
Energy Efficient Maneuvering of Connected and Automated Vehicles
Authors: Rengarajan Sankar , Hotz Scott , Sarlashkar Jayant , Gankov Stanislav , Bhagdikar Piyush , Gross Michael C. , Hirsch Charles
Published: April 2020

Onboard sensing and external connectivity using Vehicle-to-Vehicle (V2V), Vehicle-to-Infrastructure (V2I) and Vehicle-to-Everything (V2X) technologies allows a vehicle to "know" its future operating environment with some degree of certainty, greatly narrowing prior information gaps. The increased development of such connected and automated vehicle systems, currently used mostly for safety and driver convenience, presents new opportunities to improve the energy efficiency of individual vehicles [1, 2, 3, 4, 5]. Southwest Research Institute (SwRI) in collaboration with Toyota Motor North America and University of Michigan is currently working on improving energy consumption of a Toyota Prius Prime 2017 by 20%. This paper will provide an overview of the various algorithms that are being developed to achieve the energy consumption target. Custom tools such as a traffic simulator was built to model traffic flow in Fort Worth, Texas with sufficient accuracy. The benefits of a traffic simulator are two-fold: (1) generation of repeatable traffic flow patterns and (2) evaluation of the robustness of control algorithms by introducing disturbances. The traffic simulator is integrated with a high-precision hub dynamometer for testing the various control algorithms in a controlled environment. Vehicle testing results from the hub dynamometer is presented.
Compatibility of Elastomers with Polyoxymethylene Dimethyl Ethers and Blends with Diesel
Authors: Kass Michael , Wissink Martin , Janke Chris , Connatser Raynella , Curran Scott
Published: April 2020

Polyoxymethylene dimethyl ethers (PODEs) have shown promise as candidates for diesel fuel blendstocks due to their low sooting tendency, high cetane number, and diesel-comparable boiling point range. However, there is a lack of literature regarding compatibility of PODEs with common automotive elastomers, which would be a prerequisite to their adoption into the marketplace. To address this need, an exposure study and complementary solubility analysis were undertaken. A commercially available blend of PODEs with polymerization degree ranging from 3 to 6 was blended with diesel certification fuel at 0, 33, 50, 67, at 100% by mass. Elastomer coupons were exposed to the various blends for a period of 4 weeks and evaluated for volume swell. The elastomer materials included multiple fluoroelastomers (Viton and fluorosilicone) and acrylonitrile butadiene rubbers (NBR), as well as neoprene, polyurethane, epichlorohydrin (ECO), PVC-nitrile blend (OZO), ethylene propylene diene monomer (EPDM), styrene-butadiene rubber (SBR), and silicone. The exposure results indicated overall poor compatibility for PODE, with every elastomer except for fluorosilicone exhibiting greater than 30% volume swell at the 33% blend level. The general trend across the elastomers was either a consistent increase in volume swell with PODE concentration, or maximum in volume swell at an intermediate blend fraction. One notable exception is EPDM, which is not generally compatible with diesel fuel and which exhibited a reduction in volume swell with increasing PODE concentration. The same elastomers and PODE/diesel blends were evaluated using Hansen solubility parameter analysis, which predicted similar trends to the exposure study with the exception of ECO. From these results, we conclude that adoption of PODEs as a diesel fuel blendstock will require either the development of specialized elastomers, or that the blend fraction be kept to a low level to maintain compatibility with existing elastomers.

Notice: This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the US Department of Energy (DOE). The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan).
The GTU: A New Realistic Generic Pickup Truck and SUV Model
Authors: Woodiga Sudesh , Howard Kevin , Norman Paul , Lewington Neil , Carstairs Robert , Hupertz Burkhard , Chalupa Karel
Published: April 2020

Traditionally, ground vehicle aerodynamics has been researched with highly simplified models such as the Ahmed body and the SAE model. These models established and advanced the fundamental understanding of bluff body aerodynamics and have generated a large body of published data, however, their application to the development of passenger vehicles is limited by the highly idealized nature of their geometries. To date, limited data has been openly published on aerodynamic investigations of production vehicles, most likely due to the proprietary nature of production vehicle geometry. In 2012, Heft et al. introduced the realistic generic car model ‘DrivAer’ that better represents the flow physics associated with a typical production vehicle. The introduction of the DrivAer model has led to a broad set of published data for both experimental and computational investigations and has proven itself invaluable as a correlation and calibration tool of wind tunnels, the validation of computational fluid dynamics (CFD) codes and increasing the understanding of the fundamental flow physics around passenger vehicles.

Automotive sales trends in the United States, published by the Bureau of Economic Analysis in 2018, indicate that sales of Pickup Trucks (PUs) and Sports Utility Vehicles (SUVs) have increased over the past 10 years and are outselling sedans at a rate just over two to one. Compared to sedans, PU and SUV body styles pose additional aerodynamic challenges due to their complex wake structures. The introduction of a realistic generic PU and SUV model as an open access tool is expected to yield benefits to the wider community, equivalent to those of the DrivAer passenger vehicle. This paper introduces the Generic Truck Utility (GTU) as a realistic, generic PU truck and interchangeable SUV model. The paper will focus on the design and development of the GTU and will present a summary of preliminary experimental results of the GTU complemented by numerical simulations using iconCFD®, an open source based CFD solver.
A Novel Assessment and Administration Method of Autonomous Vehicle
Authors: Wang Zhao , Sun Hang , Zhang Hang , Xie Hanguang , Chen Zhenyu
Published: April 2020

As a promising strategic industry group that is rapidly evolving around the world, autonomous vehicle is entering a critical phase of commercialization from demonstration to end markets. The global automotive industry and governments are facing new common topics and challenges brought by autonomous vehicle, such as how to test, assess, and administrate the autonomous vehicle to ensure their safe running in real traffic situations and proper interactions with other road users. Starting from the facts that the way to autonomous driving is the process of a robot or a machine taking over driving tasks from a human. This paper summarizes the main characteristics of autonomous vehicle which are different from traditional one, then demonstrates the limitations of the existing certification mechanism and related testing methods when applied to autonomous vehicle. Based on the above analysis, a novel assessment mechanism focusing on complete vehicle behaviors is proposed, which takes safety, timeliness, accuracy, and smoothness as the four rules of autonomous vehicles. Then, a novel comprehensive evaluation scheme based on scenario is proposed, which combines simulation test, real vehicle test and verification test under actual driving situation. In addition, a novel administration mechanism covering vehicle development, type approval and in-use management is proposed to address the fact that the performance of autonomous vehicles is dominated by software rather than hardware and is changed by software updates throughout the life of the vehicle.
An Electric Motor Thermal Bus Cooling System for Vehicle Propulsion - Design and Test
Authors: Shoai Naini Shervin , Miller Richard , Wagner John , Rizzo Denise , Sebeck Katherine
Published: April 2020

Automotive and truck manufacturers are introducing electric propulsion systems into their ground vehicles to reduce fossil fuel consumption and harmful tailpipe emissions. The mobility shift to electric motors requires a compact thermal management system that can accommodate heat dissipation demands with minimum energy consumption in a confined space. An innovative cooling system design, emphasizing passive cooling methods coupled with a small liquid system, using a thermal bus architecture has been explored. The laboratory experiment features an emulated electric motor interfaced to a thermal cradle and multiple heat rejection pathways to evaluate the transfer of generated heat to the ambient surroundings. The thermal response of passive (e.g., carbon fiber, high thermal conductivity material, thermosyphon) and active cooling systems are investigated for two operating scenarios. The test results demonstrate that up to 93% improvement can be achieved in cooling system energy consumption during a light load electric motor condition while maintaining a target core temperature of 70°C. The governing thermal system dynamics will be reviewed in discussion of the experimental observations.
Apparent Soot Size and Concentration in Combusting Diesel Jets at High Gas Pressures and Temperatures Measured by Combining Quasi-Simultaneous LII, Elastic Light Scattering and Light Extinction
Authors: Ochoterena Raul , Andersson Mats , Andersson Sven
Published: April 2020

A method for measuring apparent soot particle size and concentration in turbulent combusting diesel jets with elevated and inhomogeneous optical density is presented and discussed. The method is based on the combination of quasi-simultaneous Laser Induced Incandescence (LII), Elastic Scattering (ELS) and Light Extinction (LE) measurements exhibiting a high potential for spatially resolved measurements of carbonaceous particles in flames and residual gases at a given instant. The method evaluates the LII signal by calculating the laser fluence across the flame and compensating for signal trapping, allowing measurements where laser extinction between the flame borders reaches values up to 90%. The method was implemented by measuring particle size and concentration in the middle sagittal axis of optically dense, combusting diesel jets at a certain time after the start of combustion. Experiments were carried out in the Chalmers High Pressure, High Temperature spray rig under conditions similar to those prevailing in direct injected compression ignition engines. Measurements of apparent particle size and concentration together with volume fraction conferring an instantaneous single-shot case and an average measurement from several consecutive jets are presented and discussed.
Driver Response to Left Incurring Path Intrusions at Sign-Controlled Intersections
Authors: Ziraldo Erika , Attalla Shady , Kodsi Sam , Oliver Michele
Published: April 2020

Straight intersecting path or “side” collisions account for 12% of all motor vehicle crashes and 24% of fatalities. While previous research has examined driver responses to hazards striking from the right (near side), no research has quantified driver responses to hazards striking from the left (far side) of an intersection. The purpose of this study was to measure driver response time (DRT) and response choice for two versions of this scenario. In one condition, the hazard vehicle was initially stopped at the intersection before accelerating into the path of the participant driver. In the other condition, the hazard vehicle approached and entered the intersection while moving at a constant speed of 50 km/h.

Testing was conducted using an Oktal full car driving simulator. 107 licenced drivers (NFemale = 57, NMale = 50) completed a short familiarization drive followed by the experimental drive in which they encountered both the initially stopped and moving conditions of the straight path hazard, in a counterbalanced order. DRT was defined as the time between when the hazard vehicle crossed a trigger located two meters from the curb until the driver reacted either by touching the brake pedal or swerving.

The average DRT was 0.08 seconds in the initially moving hazard condition and 2.39 seconds in the stopped condition. In the moving condition, many participants were able to anticipate the hazard before it crossed the defined starting location. To account for the more obvious hazard precursor in the moving condition, a geographic location further from the intersection is proposed as the starting location for measuring DRT in gradually developing hazard scenarios. There was also a significant difference in DRT (F (2) = 5.55, p = 0.005) based on the avoidance action taken. Drivers who braked and steered had the longest response times and they were also more likely to get into a collision.
A Study of Wear Mechanism on Upper Surface of Piston Top Ring Groove
Authors: Sato Kenji , Takahashi Katsuyuki , Wakabayashi Ryo , Yoshii Kenta , Takahashi Shinichi
Published: April 2020

During engine durability tests (peak power, constant engine speed) conducted in the development process, it has been the case that excessive wear has occurred to the upper surfaces of the piston top ring grooves, despite the fact that contact pressure due to combustion pressure has been low. This has resulted in considerable increases in development man-hours. The research discussed in this paper therefore set out to conduct a factor analysis of wear on the upper surfaces of piston top ring grooves in order to elucidate the wear mechanism in petrol engine for passenger car. This paper will discuss the test method employed in the factor analysis and the mechanism of wear demonstrated by the analysis. First, the form of the wear was analyzed, and rig test methods able to reproduce wear were developed. With regard to the form of wear, both sliding and impact modes were observed. Sensitivity analyses for each form of wear were conducted using rig tests. Quality engineering was employed in the tests, and sensitivity was analyzed based on the design of experimental method. Following this, an engine motoring test method was developed that was closer to the operating state of an actual engine, and that allowed tests to be simply conducted. This motoring test was able to reproduce a compound form of wear produced by sliding and impact, equivalent to that observed in an actual engine, and verified the accuracy of the factor sensitivity demonstrated in the rig tests. In addition, the motoring test was able to reproduce asymmetrical wear in the direction of the circumference of the grooves, which could not be reproduced in the rig test, and made it possible to elucidate the causes of this wear. Finally, an actual engine test was conducted combining the highest and lowest of the determined sensitivities, confirming the validity of the identified wear factors.
Evaluation Methodologies in the Development of Dynamically Reconfigurable Systems in the Automotive Industry
Authors: Oszwald Florian , Bertelo Ruben , Gericota Manuel , Becker Juergen
Published: April 2020

Classical decentralized architectures based on large networks of microprocessor-based Electronic Control Units (ECU), namely those used in self-driving cars and other highly-automated applications used in the automotive industry, are becoming more and more complex. These new, high computational power demand applications are constrained by limits on energy consumption, weight, and size of the embedded components. The adoption of new embedded centralized electrical/electronic (E/E) architectures based on dynamically reconfigurable hardware represents a new possibility to tackle these challenges. However, they also raise concerns and questions about their safety. Hence, an appropriate evaluation must be performed to guarantee that safety requirements resulting from an Automotive Safety Integrity Level (ASIL) according to the standard ISO 26262 are met.

In this paper, a methodology for the evaluation of dynamically reconfigurable systems based on centralized architectures is presented. The aim is to evaluate the reliability and probability of failure while exploring the design space without compromise the overall system performance.

The methodology is divided into three stages. In the first stage, the system is decomposed, and its sub-systems are isolated before applying a Fault Tree Analysis on the elements of each sub-system. The mathematical stochastic model of Markov Chain is used in the second stage to obtain the reliability function and the quantification of the Mean Time to Failure (MTTF) of the system. Finally, the overall system is evaluated in terms of performance, and according to time constraints such as reconfiguration latency in case of failure.

Applying this method, we quantify the MTTF in Failure in Time (FIT) format of an E/E architecture. Additionally, we evaluate each sub-system independently and obtain the respective ASIL decomposition of the overall system. The aim is to evaluate the migration of safety-related functionalities/redundancy from traditional architectures into reprogrammable devices.

With the application of this methodology, we can evaluate the reliability and performance of dynamically reconfigurable systems and define new E/E automotive architectures.
Trainee and Program Director Perspectives on Meaningful Patient Attribution and Clinical Outcomes Data
Authors: Rosenbluth Glenn , Tong Michelle S. , Montes Shivany Y. Condor , Boscardin Christy
Published: April 2020

Background

The Accreditation Council for Graduate Medical Education specifies that trainees must receive clinical outcomes and quality benchmark data at specific levels related to institutional patient populations. Program directors (PDs) are challenged to identify meaningful data and provide them in formats acceptable to trainees.

Objective

We sought to understand what types of patients, data/metrics, and data delivery systems trainees and PDs prefer for supplying trainees with clinical outcomes data.

Methods

Trainees (n = 21) and PDs (n = 12) from multiple specialties participated in focus groups during academic year 2017–2018. They described key themes for providing clinical outcomes data to trainees.

Results

Trainees and PDs differed in how they identified patients for clinical outcomes data for trainees. Trainees were interested in encounters where they felt a sense of responsibility or had autonomy/independent decision-making opportunities, continuity, or learned something new; PDs used broader criteria including all patients cared for by their trainees. Both groups thought trainees should be given trainee-level metrics and consistently highlighted the importance of comparison to peers and/or benchmarks. Both groups found value in “push” and “pull” data systems, although trainees wanted both, while PDs wanted one or the other. Both groups agreed that trainees should review data with specific faculty. Trainees expressed concern about being judged based on their patients' clinical outcomes.

Conclusions

Trainee and PD perspectives on which patients they would like outcomes data for differed, but they overlapped for types of metrics, formats, and review processes for the data.
On the ice-nucleating potential of warm hydrometeors in mixed-phase clouds
Authors: Krayer Michael , Chouippe Agathe , Uhlmann Markus , Dušek Jan , Leisner Thomas
Published: April 2020

Abstract. The question whether or not the presence of warm hydrometeors in clouds may play a significant role in the nucleation of new ice particles has been debated for several decades. While the early works of Fukuta and Lee (1986) and Baker (1991) indicated that it might be irrelevant, the more recent study of Prabhakaran et al. (2019) suggested otherwise. In this work, we are aiming to quantify the ice-nucleating potential using high-fidelity flow simulation techniques around a single hydrometeor and use favorable considerations to upscale the effects to a collective of ice particles in clouds. While we find that ice nucleation may be enhanced in the vicinity of a warm hydrometeor by several orders of magnitude and that the affected volume of air is much larger than previously estimated, it is very unlikely that this effect alone causes the rapid enhancement of ice nucleation observed in some types of clouds, mainly due to the low initial volumetric ice concentration. Nonetheless, it is suggested to implement this effect into existing cloud models in order to investigate second-order effects such as ice nucleus preactivation or enhancement after the onset of glaciation.
Measurement report: Short-term variation of ammonia concentration in an urban area: contributions of mist evaporation and emissions from a forest canopy with bird droppings
Authors: Osada Kazuo
Published: April 2020

Abstract. Short-term variations of NH3 concentrations in the urban atmosphere are affected by local meteorological conditions and variations of natural and anthropogenic sources. To investigate potential sources and processes of NH3 variation in an urban area, hourly NH3 and NH4+ concentrations were measured from November 2017 through October 2019 in Nagoya, a megacity located in central Japan. Monthly averages of NH3 concentrations were high in summer and low in winter. Daily minimum NH3 concentrations were almost linearly correlated with daily minimum air temperature. In contrast, daily maximum NH3 concentrations revealed an exponential increase with temperature, suggesting that different processes with air temperature acted during the nighttime and daytime. Short-term increases of NH3 concentrations of two types were examined closely. The first is a rare but large increase (11 ppb for 2 hr) after mist evaporation during daytime. It is noteworthy that an event of this magnitude was identified only once during two years of observations at Nagoya even though evaporation of mist or fog droplets is expected to be frequent after rain. The second short-term increase was a large morning peak in summer. After selected days were fulfilled with non-wet and weak wind conditions, the amplitude of diurnal variation of NH3 concentration (daily maximum minus minimum) was analyzed: the amplitude was small (ca. 2 ppb) in winter but it increased from early summer along with new leaf growth. It peaked in summer (up to ca. 20 ppb) during intense addition of droppings from hundreds of crows on trees in the campus assembled before roosting. The high daily maximum NH3 concentration was characterized by a rapid increase occurring 2–4 hr after local sunrise. Daily and seasonal findings related to the morning peak implied that stomatal emission at the site was responsible for the increase. The yearly difference between daily amplitudes during the two summers was explained by the difference in the input amounts of reactive nitrogen derived from bird droppings and some rain, suggesting that the canopy of a small forest affected by the bird droppings might act as a temporary but strong source of NH3.
Intercomparison and Evaluation of Ground- and Satellite-Based Stratospheric Ozone and Temperature profiles above Observatoire Haute Provence during the Lidar Validation NDACC Experiment (LAVANDE)
Authors: Wing Robin , Steinbrecht Wolfgang , Godin-Beekmann Sophie , McGee Thomas J. , Sullivan John T. , Sumnicht Grant , Ancellet Gerard , Hauchecorne Alain , Khaykin Sergey , Keckhut Philippe
Published: April 2020

Abstract. A two-part inter-comparison campaign was conducted at L'Observatoire de Haute Provence (OHP) for the validation of lidar ozone and temperature profiles using the mobile NASA Stratospheric Ozone Lidar (NASA STROZ), satellite overpasses from the Microwave Limb Sounder (MLS), the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER), meteorological radiosondes launched from Nimes, and locally launched ozonesondes. All the data were submitted and compared blind, before the group could see results from the other instruments. There was good agreement between all ozone measurements between 20 and 40 km with differences of generally less than 5 % throughout this region. Below 20 km SABER and MLS measured significantly more ozone than the lidars or ozone sondes. Temperatures for all lidars were in good agreement between 30 and 60 km with differences on the order of ±1 to 3 K. Below 30 km, the OHP lidar operating at 532 nm has a significant cool bias due to contamination by aerosols. Systematic, altitude varying bias up to ±5 K compared to the lidars was found for MLS at many altitudes. SABER temperature profiles are generally closer to the lidar profiles, with up 3 K negative bias near 50 km. Uncertainty estimates for ozone and temperature appear to be realistic for nearly all systems. However, it does seem that the very low estimated uncertainties of lidars between 30 and 50 km, between 0.1 and 1 K, are not achieved during LidAr VAlidation NDacc Experiment (LAVANDE). These estimates might have to be increased to 1 to 2 K.
The fate of upwelled nitrate off Peru shaped by submesoscale filaments and fronts
Authors: Hauschildt Jaard , Thomsen Soeren , Echevin Vincent , Oschlies Andreas , José Yonss Saranga , Krahmann Gerd , Bristow Laura A. , Lavik Gaute
Published: April 2020

Abstract. Filaments and fronts play a crucial role for a net offshore and downward nutrient transport in Eastern Boundary Upwelling Regions (EBUS) and thereby reduce primary production. Often studies are either based on observations or model simulations but seldom both approaches are combined quantitatively to assess the importance of filaments for primary production and nutrient transport. Here we combine targeted interdisciplinary shipboard observations of a cold filament off Peru with submesoscale-permitting (1/45°) coupled physical (CROCO) and biogeochemical (PISCES) model simulations to (i) evaluate the model simulations in detail, including the timescales of biogeochemical modification of the newly upwelled water and (ii) quantify the net effect of submesoscale fronts and filaments on primary production of the Peruvian upwelling system. The observed filament contains relatively cold, fresh and nutrient-rich waters originating in the coastal upwelling. Enhanced nitrate concentrations and offshore velocities of up to 0.5 m s−1 within the filament suggest an offshore transport of nutrients. Surface chlorophyll in the filament is a factor 4 lower than at the upwelling front while surface primary production is a factor 2 higher, highlighting the additional value of direct rate measurements for model validation. The simulation exhibits filaments that are similar in horizontal and vertical scale compared to the observed filament. Nitrate concentrations and primary pro- duction within filaments in the model are comparable to observations as well, justifying further analysis of nitrate uptake and subduction using the model. Virtual Lagrangian floats were released in the subsurface waters along the shelf and biogeochemical variables tracked along the trajectories of floats upwelled near the coast. In the submesoscale-permitting (1/45°) simulation 43.0 % of upwelled floats and 40.6 % of upwelled nitrate is subducted within 20 days after upwelling, which corresponds to an increase of nitrate subduction compared to a mesoscale-resolving (1/9°) simulation by 13.9 %. This suggests that submesoscale processes further reduce primary production by amplifying the downward and offshore export of nutrients found in previous mesoscale studies, which are thus likely to underestimate the reduction in primary production due to eddy-fluxes. Moreover, this downward and offshore transport could also enhance the export of fresh organic matter below the photic zone and thereby potentially stimulate microbial activity in the upper offshore oxygen minimum zone.
Disdrometer measurements under Sense-City rainfall simulator
Authors: Gires Auguste , Bruley Philippe , Ruas Anne , Schertzer Daniel , Tchiguirinskaia Ioulia
Published: April 2020

Abstract. The Hydrology, Meteorology and Complexity Laboratory of École des Ponts ParisTech (http://hmco.enpc.fr, last access: 24 March 2020) and the Sense-City consortium (http://sense-city.ifsttar.fr/, last access: 24 March 2020) made available a dataset of optical disdrometer measurements stemming from a campaign that took place in September 2017 under the rainfall simulator of the Sense-City climatic chamber, which is located near Paris. Two OTT Parsivel2 disdrometers were used. The size and velocity of drops falling through the sampling area of the devices of roughly a few tens of square centimetres are computed by disdrometers. This enables the estimation of the drop size distribution and the further study of rainfall microphysics or kinetic energy for example. Raw data – basically a matrix containing a number of drops according to classes of size and velocity, along with more aggregated ones such as rain rate and drop size distribution with filtering – are available. The dataset is publicly available at https://doi.org/10.5281/zenodo.3347051(Gires et al., 2019).
Rivers in the sky, flooding on the ground
Authors: Ionita Monica , Nagavciuc Viorica , Guan Bin
Published: April 2020

Abstract. The role of the large scale atmospheric circulation and atmospheric rivers (ARs) in producing extreme flooding and heavy rainfall events in the lower part of Rhine River catchment area is examined in this study. Analysis of the largest 10 floods in the lower Rhine, between 1817–2015, indicate that all these extreme flood peaks have been preceded up to 7 days in advance by intense moisture transport from the tropical North Atlantic basin, in the form of narrow bands, also know as atmospheric rivers. The influence of ARs on the Rhine River flood events is done via the prevailing large-scale atmospheric circulation. Most of the ARs associated with these flood events are embedded in the trailing fronts of the extratropical cyclones. The typical large scale atmospheric circulation leading to heavy rainfall and flooding in the lower Rhine is characterized by a low pressure center south of Greenland which migrates towards Europe and a stable high pressure center over the northern part of Africa and southern part of Europe. The days preceding the flood peaks, lower (upper) level convergence (divergence) is observed over the analyzed region, which is an indication of strong vertical motions and heavy rainfall. The results presented in this study offer new insights regarding the importance of tropical moisture transport as driver of extreme flooding in the lower part of Rhine River catchment area and we show for the first time that ARs are an useful tool for the identification of potential damaging floods inland Europe.