bluuebunny/crossref_metadata_2025 huggingface dataset:
Physio-Feedback and Exercise Program (PEER) Improves Balance, Muscle Strength, and Fall Risk in Older Adults
Authors: Thiamwong Ladda , Stout Jeffrey R. , Sole Mary Lou , Ng Boon Peng , Yan Xin , Talbert Steven
Published: April 2020

A one-group pre/posttest study was conducted to examine the feasibility and effect size of an 8-week physio-feedback and exercise program (PEER) on improving balance, muscle strength, and fall risk. Nineteen participants (mean age = 76 years) received the intervention, which included visual physio-feedback by the BTrackS™ Assess Balance System, cognitive reframing, and a combined group- and home-based exercise program by a trained peer coach. Pre- and post-measurement outcomes were evaluated for balance, handgrip strength, and fall risk. Feasibility was assessed by dropout rate, safety, and adherence to exercise. Significant improvements were noted in dynamic balance (Sit-to-Stand, Timed Up & Go tests), handgrip strength, and fall risk. Participants' attendance was 87.5%, with no fall incidence. The physio-feedback, cognitive reframing, and peer coaching facilitate older adults to align their perceived fall risk with physiological fall risk and motivate them to stay active. PEER intervention is feasible; safe; improves balance, muscle strength, and fall risk; and may enhance activity engagement.

Targets:

Community-dwelling older adults.

Intervention Description:

Provide visual physio-feedback and cognitive reframing based on the fall risk appraisal matrix and participate in combined group- and home-based exercises by a trained peer coach.

Mechanism of Action:

Align perceived and physiological fall risk, peer coaching to exercise.

Outcomes:

Balance, handgrip strength, fall risk, and activity engagement.

[
Research in Gerontological Nursing, 13
(6), 289–296.]
Surface Modification of Low Carbon Steel by Using Electrophoretic Deposition Technique with Graphene Oxide Powder
Authors: Nemee Pichawan , Jaitanong Nittaya , Narksitipan Suparut
Published: April 2020

In this research, low carbon steel surface was modified using electrophoretic deposition (EPD) technique from a graphene oxide (GO) water suspension. The electrophoretic deposition (EPD) is the technique used for manipulation and deposition of nanomaterials. The GO coating was used as a layer to increase the hardness of low carbon steel. GO was successfully synthesized using the modified Hummers method. EPD technique was performed by applying voltage at 9 volts and the deposition time of 15 mins. The working distance between the cathode and anode was fixed at 15 mm. The GO film had been deposited by EPD technique where it was carburized at 900, 950, 1000 and 1050°C, for 60 mins. The microstructure of the carbide film was investigated using scanning electron microscopy (SEM). As the carburization temperature raised (1050°C), more volume carbon atoms reacted with iron atoms to form iron carbon (Fe3C) layer on to the substrate surface. The carbide films are columnar crystal growth with a particle size of approximately 50 μm. The growth rate of the carbide films at 1050°C is about 8 µm/min. Energy dispersive X-ray spectrometer (EDS) was studied for chemical elements analysis. Fe, C and O elements were then detected. At carburization temperature of 1050°C, it showed that C element distribution is higher than others’ temperatures. Moreover, the hardness on the carbide films was investigated using a Vickers hardness tester under an applied load of 500 grams for 10 seconds. It was found that the hardness increased with the increasing carburization temperatures. The hardness of low carbon steel is 172.99 ± 2.28 HV. After the carburization processing via GO at temperature of 1050°C, the highest hardness of 821.42 ± 35.33 HV was obtained. It was observed that the mechanical properties of low carbon steel surface were found to be strongly influenced by the process of carburization temperature.
Application of Microwave Radiation in Modified Polyol Process for Synthesis Pure, Te-Doped, and Sn-Doped CoSb3 Thermoelectric Materials
Authors: Kapanya Thammanoon , Thanachayanont Chanchana , Tuantranont Adisorn , Sarakonsri Thapanee
Published: April 2020

Synthesis routes of CoSb3 need a long reaction time, especially at high temperature and-/or high pressure. Although the modified polyol process assisted with microwave radiation can be used to solve these problems, it used the excess amount of Sb ion. Therefore, this study aimed to solve this drawback by retarding the rate of reduction. The different microwave times (0, 1, and 3 min) were investigated to find out the shortest heating duration for preparing CoSb3 nanoparticles. Te-doped and Sn-doped CoSb3 were synthesized to investigate the benefit of this synthesis method for increasing the solubility limit of Te and Sn in the CoSb3 structure. The phase and microstructure of the synthesized products were characterized by using x-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results showed that the high crystalline phase of CoSb3 (JCPDS: 78-0977) without any metallic impurity phases product was successfully synthesized in 3 minutes for a heating time at normal pressure, non-excessive addition of Sb ion precursor, and low temperature. The XRD results of Te-doped and Sn-doped CoSb3 products exhibited poor crystalline phase and hard to exactly identify. In SEM and TEM results, the CoSb3 powder consisted of very tiny spherical-like particles around 10 nanometers attaching together even at different microwave time similar to Te-doped/Sn-doped samples.
Study on Effect of Inductively Coupled Ar/O2 Plasma in E- and H-Mode on Riceberry Rice by SEM/EDS
Authors: Wangkanai Jidchanok , Poonsawat Kittawat , Sopan Sakulrat , Wongsagonsub Rungtiwa , Suphantharika Manop , Suwannalert Prasit , Dangtip Somsak
Published: April 2020

Riceberry brown rice is regarded as a source of various nutrients; often richer than white rice. Non-thermal plasma has recently been gaining a role for improving properties of cereal grains, especially brown rice. A number of methods of plasma treatment has been proposed including discharges as capacitive coupled plasma (CCP) and inductive coupled plasma (ICP). ICP has two operation modes as capacitive (E-mode) and inductive (H-mode) discharge with rather distinct characters. In this study we have focused on using ICP Ar/O2 plasma in both E-and H mode for plasma treatment on riceberry brown rice. The input power for plasma generation were set to 50 and 250 W for E-and H-mode, respectively. Plasma in H-mode was having higher plasma density than that in E-mode, as observed in the optical emission spectrum. The surface morphology of riceberry brown rice before and after Ar/O2 plasma treatment was evaluated using a scanning electron microscope without or with an energy dispersive spectroscopy (SEM and SEM/EDS). It has been found that the bran layer was richer in elemental compositions than the endosperm. The surface of rice sample was found to be etched and more porous after plasma treatment. The Ar/O2 plasma in H-mode was observed to offer higher effect. The surface contact angle was found to decrease from 120.1o ± 0.9o in untreated samples to 79.3o ± 0.6o and 99.2o ± 0.8o in plasma treated samples on E-and H-mode, respectively.
Electron Microscopy Investigation of Rice Husk-Derived Silicon-Tin/Nitrogen-Doped Graphene Composites Nanostructure
Authors: Laokawee Viratchara , Autthawong Thanapat , Chayasombat Bralee , Yu Aishui , Sarakonsri Thapanee
Published: April 2020

Nowadays, there is an increasing of the demanding in high energy density lithium-ion batteries (LIBs) due to the growing of energy storage needs for electronic vehicles and portable devices. Silicon (Si) and Tin (Sn) are the promising anode materials for LIBs due to their high theoretical capacity of 4200 mAh/g and 994 mAh/g. Moreover, Si can be derived from rice husk which is the main agricultural product in Thailand. However, the using of Si and Sn encounters with the huge volume expansion during lithiation and delithiation process. To alleviate this problem, Nitrogen-doped graphene (NrGO), carbon supporter, is used as composite with these metals to buffer the volume change and increase the electrical conductivity of composites. This work aims to synthesis Si/NrGO and SiSn/NrGO nanocomposites and Si used in these composites is derived from rice husk. All products were characterized by X-rays diffraction (XRD), Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. XRD results showed that the composites contained phases of Si, Sn and carbon. The electron microscopy techniques were the main part to clarify the morphology and distribution of Si and Sn particles on NrGO. SEM and TEM results confirm that there were small sized particles of Si and Sn dispersed and covered on NrGO surface. Furthermore, the electrochemical properties of prepared composites were measured to confirm their efficiency as anode materials in lithium-ion batteries by coin cell assembly. The composite with 10 percent Si and 10 percent Sn on NrGO could deliver a high capacity around 480 mAh/g over 100 cycles and expected to use as anode materials in the next generation lithium-ion batteries.
Microstructure and Mechanical Performance of Fiber-Reinforced Cement Composites Made with Nucleating-Agent Activated Coal-Fired Power Plant Bottom Ash
Authors: Sonprasarn Passakorn , Chakartnarodom Parinya , Kongkajun Nuntaporn , Prakaypan Wichit
Published: April 2020

The purpose of this work was to study the microstructure and the mechanical properties of the fiber-reinforced cement composites that used the nucleating-agent activated coal-fired power plant bottom ash as a raw material in the mixture for producing the composites. The raw materials for producing the fiber reinforced cement composites were the ordinary Portland cement (OPC), natural gypsum, cellulose fiber, and bottom ash. The bottom ash was chemically treated by the nucleating agent, a chemical that was prepared by the precipitation process from the aqueous solutions of sodium silicate (Na2SiO3) and calcium nitrate (Ca (NO3)2). To prepare the samples, the mixture consisting of 34.75 wt% OPC, 34.75 wt% bottom ash, 25 wt% natural gypsum, and 5.5 wt% cellulose fiber was mixed with the nucleating agent at the amount of 0 to 4.5 % of OPC weight in the mixture, and water to form the slurry. Then, the samples were produced by filter pressing process and cured in the autoclave for 16 hrs at 180 °C, and 10 bars. The mechanical properties of the samples including modulus of rupture (MOR), modulus of elasticity (MOE), and toughness were characterized by the universal testing machine (UTM). The microstructures of the samples were observed by scanning electron microscope (SEM). The results showed that the utilization of nucleating agent affect the microstructure of the sample leading to the improvement in the mechanical properties of samples.
DIGITAL TERRAIN MODELING USING FINITE ELEMENT METHODS MESHLESS
Authors: Da Silva Francisco Assis , Scandolieri Gustavo R. , Pereira Danillo R. , Helton M. Sapia, João F. C. Silva Leandro L. Almeida,
Published: April 2020

Digital Terrain Modeling (DTM) is a computational model of the earth surface that represents relief and it has a wide range of applications. This work proposes a new approach to DTM using the Finite Element Method (FEM) point-based instead of mesh-based. The points used by the proposed methodology were obtained by data captured by satellite images. The most methods require the precomputation of a mesh on the surface of the terrain. Our methodology overcomes the mesh step, so the modeling process is very fast.
IMPACT OF USING RECYCLED AGGREGATES ON COMPRESSIVE STRENGTH OF CONCRETE
Authors: Naouaoui Khaoula , Bouyahyaoui Azzeddine , Cherradi Toufik
Published: April 2020

Recycled aggregate concrete is considered the next generation in the field of construction: it respects the environment, solves the problem of debris management and is economically profitable. In order to better adapt its use, technical studies, experimental studies and simulations are carried out in all research centers around the world in order to define its field of application. Our study falls within this framework. It is concerned with the study of the mechanical characteristics of recycled aggregate concrete essentially the compression test for various percentages of replacement. The purpose of this study is to confirm the results of studies by other researchers and to find techniques that will maximize the replacement of natural aggregates with recycled aggregates. The concrete chosen for these tests is an old building in the region of Rabat, Morocco which has been built more than 40 years and demolished in the year of 2017. The tests carried out showed a decrease in the compressive resistance noted when the replacement rates exceed 50% rate. The first improvement methods were put in place and being tested: the partial replacement of cement with pozzolan (20% rate) known by his improving of the compressive strength for ordinary concrete, the partial replacement of the large proportion [12.5-31.5] only in recycled concrete and work with natural gravels. Other improvements will be proposed as the studies progress.
USE OF GEOSYNTHETIC CLAY LINER AS A WATERPROOFING BARRIER IN SANITARY LANDFILLS
Authors: Visentin Caroline , Zanella Pedro Nicola , Kronhardt Bruna Koppe , Trentin Adan William da Silva , Braun Adeli Beatriz , Thomé Antônio
Published: April 2020

One of the main sources of soil and water (superficial and subterranean) contamination is the inadequate solid waste disposal. In this sense, sanitary landfills have great importance for environmental protection, and in these systems, the geosynthetics materials, such as the Geosynthetic Clay Liner (GCL), are widely employed. However, for landfills with leachate recirculation, the application of GCL is vetoed by many government agencies. In view of this, this study sought to provide an analysis of recent advances in application of GCL in landfill sites. For this reason, the main configurations of landfills and characteristics of its leachate were presented, as well as of the GCL by means of case studies applied to the context. The results indicated that the most important parameter to be evaluated in GCL performance is its hydraulic conductivity, which can be influenced directly by leachate composition (conventional and recirculated) as to the presence of cations and anions. Thus, it is concluded that the evaluation of these characteristics is essential to ensure the proper performance of GCL in landfills.
THE USE OF VECTOR-BASED GIS BOOLEAN ANALYSIS TECHNIQUE TO DETERMINE THE BEST LOCATION FOR A MUNICIPAL SOLID WASTE LANDFILL SITE IN MAFRAQ GOVERNORATE/ JORDAN
Authors: Al- Shabeeb Abdel Rahman Rakad
Published: April 2020

The choice of location for a landfill site has a significant effect on the economy, ecology and overall environmental well-being, and is therefore a vital decision in the process of city planning. In Mafraq, the huge increases in population, as a result both of the arrival of significant numbers of Syrian refugees, as well as an increasing birth rate, has increased the pressure on the limited resources available, as well as emphasising the necessity of building a proper system of waste management, as well as a well-located landfill site. In relation to the latter, the aim is to position it so as to minimise any negative impact on either the environment or on public health. In terms of GIS, vector analysis tools and multi-criteria decision analysis (MCDA) were applied to ascertain the best location for a landfill site. The aspects that were assessed in this research included slopes, roads, airport, wells, soil, faults, international borders, Wadis, and urban areas. The weighting given to each item was determined using the Boolean technique in terms of its importance to the location of a landfill site. The conclusions indicated that 18 sites in the area researched were potentially suitable for landfill sites, but that the Jordanian government had to undertake further work using the results of the GIS research to determine where the site should be located.
ASSESSING HUMAN AND CARBON FOOTPRINT OF RANCHI URBAN ENVIRONMENT USING REMOTE SENSING TECHNOLOGY
Authors: Kumar Amit , Kumar Ashwani
Published: April 2020

In the present study, the total carbon emission of rapidly growing Ranchi Urban Agglomeration (RUA) was estimated in geospatial environment considering certain factors. The carbon emission estimation is based on the increase in human as well as vehicular population and loss of vegetation cover employing standardized conversion factors. The rapid built-up expansion (180%) and human population growth (223%) during 1975-2010 led to innumerable socio-economic and environmental impacts including deterioration of urban ecosystem. The built-up expansion as observed through satellite images reflects degradation in the natural ecosystem primarily apparent on forest ecosystem in RUA. The study reveals that after reorganization of Ranchi as state capital (post 2000), the carbon emission was more prevalent as compared to the earlier periods. The estimates of carbon stock (terrestrial carbon) represents that the vegetation cover, attributed as the major source of carbon sink, was lost and leads to emission of total 2.44 metric tonnes of carbon during 1975-2010. The vehicular based carbon emission estimation exhibits high level of carbon emission in RUA (198,038,728 metric tonnes) during the year 2010. The population distribution pattern in wards of Ranchi Municipal Corporation revealed that the wards located in the selected city core northern, north-eastern, eastern and south-western parts emitted than the mean city carbon emission (>38,500 metric tonnes) as compared to the wards located in central, north-eastern, south-western and south-western parts (>60,000 metric tonnes). The study suggests towards urgent imposition of regulations for rapid land use transformation together with preservation and growth of carbon sink locations of RUA.
URBAN MOBILITY OF THE ELDERLY IN THE METROPOLITAN REGION OF SÃO PAULO: AN APPLICATION OH THE MULTINOMIAL LOGIT MODEL
Authors: Mação Bernal Luciana , Moreira Diniz Claudinei , Da Penha Sanches Suely
Published: April 2020

Elderly population growth has become a worldwide concern in recent years. For that matter, it is important to think about the current state of cities in a way to ensure a safe and independent transportation for the daily mobility of the elderly. Therefore, this study aimed to identify differences in the urban mobility of the elderly and non-elderly population based on travel characteristics. Data was obtained from a mobility research conducted within the metropolitan area of São Paulo, from which five variables were selected and treated for the study. The methodology was based on an analysis with a multinomial logit model. Results indicated that elderly and the non-elderly people tend to choose the individual transport mode first, followed by the public transport mode and lastly the walking mode. Moreover, non-elderly people tend to travel longer distances in their daily commutes, while the elderly people are more likely to do shorter trips in their daily commutes. In sum, the comprehension of mobility differences between elderly and non-elderly population allows a better understanding of challenges faced by the elderly in their daily mobility, as well as adequate planning for more inclusive cities.
An overview of analgesics: NSAIDs, paracetamol, and topical analgesics
Authors: Van Rensburg R. , Reuter H.
Published: April 2020

Pain is a complex and unique experience. It encompasses several pathways, involving nociceptive signal generation (transduction) and propagation (transmission), as well as perception and modulation of the nociceptive stimuli. Nonsteroidal anti-inflammatory drugs (NSAIDs) primarily exert their analgesic effects through inhibition of cyclooxygenase (COX) enzymes, thereby attenuating prostaglandin synthesis. The COX-2 selective NSAIDs (coxibs) and aspirin have also been shown to reduce colorectal cancers, presumably by prostaglandin-inhibition mechanisms. Paracetamol appears to have both peripheral and central effects. The postulated mechanism for its peripheral effects is indirect COX inhibition, while the central effects are thought to be mediated by modulation of descending pain inhibition pathways. Topical analgesics are available in various formulations. The topical NSAIDs have the same mechanism of action as the systemic formulations, but with less systemic absorption and effects. The local anaesthetics provide a dense sensory block via inhibition of nerve impulse transmission, and are available in percutaneous and transdermal preparations. Capsicum is effective for neuropathic pain, and acts by stimulating and then desensitising peripheral sensory nerves.
Depression in doctors: A bitter pill to swallow
Authors: Outhoff K.
Published: April 2020

At some point in their career, at least a third of doctors suffer personal health problems such as injury, aging, or physical and mental illness, which detract from their ability to function properly and to practice medicine safely. In most, impairment is amenable to intervention, treatment, recovery or resolution. However, some conditions, notably depression, may be overrepresented in the medical profession, under-recognized, stigmatised and undertreated, which may have fatal consequences.
An approach to acute pulmonary embolism in the primary emergency care environment
Authors: Naidoo M.
Published: April 2020

Pulmonary embolism (PE) is a common emergency presenting among high risk patients. It is important to have a structured approach to clinical assessment, diagnosis and management of this potentially life-threatening emergency. Clinical and management pathways have improved over the last 10 years as clear guidelines have emerged. Newer diagnostic modalities have become available and will hopefully improve the pick-up rate of PE and reduce the morbidity and mortality. High level evidence presented by the American Society of Haematology and the European Society of Cardiology forms the basis for this review.
Morphine spinals: ICU or ward?
Authors: Quan C.
Published: April 2020

No abstract available.
Opioid Free Anaesthesia: a paradigm shift
Authors: Anamourlis P. C.
Published: April 2020

No abstract available.
Effect of counselling on the family function of intimate partner violence victims attending antenatal clinic in a tertiary hospital in North Central Nigeria
Authors: Akor B. O. , Moses L. A. , Baamlong N. D. , Shedul L. L. , Haruna A. S. , Abu J. M. , Chira O. U. , Ripiye N. R. , Abdulkareem R. A.
Published: April 2020

Background and aim: Intimate partner violence (IPV) is a global problem. Family dysfunction is an integral characteristic of IPV homes. However, not much has been done regarding restoration of these families. The aim of this study was to explore the effect of counselling on the family function of pregnant IPV victims, with a view to recommending an appropriate interventional strategy.Methods: The study was a single-blinded randomised controlled trial of pregnant IPV victims. The Abuse Assessment Scale (AAS) was used to recruit 72 IPV victims who were randomised into the control and intervention arms of 36 each. Their sociodemographic data were collected. The family function of the victims was assessed using the SCORE-15 index of family function at the beginning the study. The intervention arm had three sessions of counselling lasting one to two hours fortnightly using the SOS DoC protocol. The family function was repeated post intervention. Data were analysed using SPSS version 20 and a p-value of 0.05 was considered significant.Results: The majority (82%) of the IPV victims had dysfunctional families. Baseline mean family function score across the groups showed no statistically significant difference. Post intervention, the mean family function score improved from 2.92 ± 0.92 to 2.16 ± 0.63 and this change was statistically significant (p 0.0001). In the control arm, the change from 2.48 ± 0.73 to 2.29 ± 0.82 was not statistically significant (p = 0.116). Conclusion: Short-term counselling significantly improved the family function of IPV victims.
The spiritual construction of depression
Authors: Ellis Chris
Published: April 2020

No abstract available.
Integrating services for impact and sustainability: a proof-of-concept project in KwaZulu-Natal, South Africa
Authors: Haskins J. Lyn , Phakathi Sifiso A. , Grant Merridy , Horwood Christiane M.
Published: April 2020

Background: Integration of services in primary health care settings can provide mother/baby pairs with all required services at one visit. This study aimed to evaluate a proof of concept, quality improvement (QI) intervention to strengthen well-child service provision and integration with maternal health services in five rural clinics in KwaZulu-Natal, South Africa.Methods: Quantitative cross-sectional surveys were conducted among mothers bringing their child for well-child services, before and after implementation of the intervention. Exit interviews and reviews of the child’s Road to Health Booklet (RTHB) were conducted to determine services provided at the visit, and the time spent in the clinic was observed and recorded.Results: A total of 413 exit interviews and record reviews were conducted (123 at baseline and 290 at follow-up). At follow-up, significantly more mothers were tested for HIV during the well-child visit (9.2% vs. 22.6%; p = 0.045) and significantly more mothers received ART (3.7% vs. 35.5%; p = 0.010). However, coverage of growth-monitoring services remained low and there was no difference in infant feeding advice provided to mothers at baseline and follow-up (49.5% vs. 49.7%; p = 0.996). More mothers interacted with a registered nurse at follow-up than at baseline (35.8% vs. 80.7%; p = 0.032).Conclusions: Over the implementation period of the QI intervention, improvement was shown in coverage and quality of some maternal health and HIV services, but there was no improvement in growth monitoring. This suggests that QI has the potentialto improve integration of service delivery, but this was a small study and further research is recommended.
A coordinate-free proof of the finiteness principle for Whitney’s extension problem
Authors: Carruth Jacob , Frei-Pearson Abraham , Israel Arie , Klartag Bo'az
Published: April 2020

We present a coordinate-free version of Fefferman’s solution of Whitney’s extension problem in the space

C^{m−1,1}(\mathbb R^n)

. While the original argument relies on an elaborate induction on collections of partial derivatives, our proof uses the language of ideals and translation-invariant subspaces in the ring of polynomials. We emphasize the role of compactness in the proof, first in the familiar sense of topological compactness, but also in the sense of finiteness theorems arising in logic and semialgebraic geometry. These techniques may be relevant to the study of Whitney-type extension problems on sub-Riemannian manifolds where global coordinates are generally unavailable.
Fusing Radar and Vision Data for Cut-In Vehicle Identification in Platooning Applications
Authors: Liu Mengke , Rathinam Sivakumar , Lukuc Mike , Gopalswamy Swaminathan
Published: April 2020

Identifying vehicles and objects in the vicinity of platooning vehicles is critical for platooning safety. A neighboring vehicle may change lanes and enter a lane with platooning vehicles. Any deployable platooning system must be able to first identify the presence of a cut-in vehicle before performing any control actions on the vehicles. In this article, a sensor fusion algorithm is presented that combines radar and vision data obtained on-board a moving truck to identify the states of the cut-in vehicle. Experimental results are presented to corroborate the performance of the proposed algorithms.
Effect of Adherent Rain on Vision-Based Object Detection Algorithms
Authors: Hamzeh Yazan , El-Shair Zaid , Rawashdeh Samir A.
Published: April 2020

Adverse weather conditions degrade the quality of images used in vision-based advanced driver assistance systems (ADAS) and autonomous driving algorithms. Adherent raindrops onto a vehicle’s windshield occlude parts of the input image and blur background texture in regions covered by them. Rain also changes image intensity and disturbs chromatic properties of color images. In this work, we collected a dataset using a camera mounted behind a windshield at different rain intensities. The data was processed to generate a set of distorted images by adherent raindrops along with ground truth data of clear images (just after a windshield wipe). We quantitatively evaluated the amount of distortion caused by the raindrops, using the Normalized Cross-Correlation and Structural Similarity methods. While most prior work in the field of rain detection and removal focuses on the image restoration aspects, they typically do not provide quantitative measures to the effect of degradation of input image quality on the performance of image-based algorithms. We quantitatively evaluated the effect of raindrop distortion on deep-learning-based object detection algorithms by comparing the detectors’ performance on the distorted images to the clear images. State-of-the-art detector algorithms were selected and used, namely, Faster Region-based Convolution Neural Network (R-CNN), Single Shot Detector (SSD) and You Only Look Once (YOLO). For the overall performance of the object detection and classification algorithms, we used standard accuracy, precision, and recall measures.
An Analytical Approach for Calculating Instantaneous Multilayer-Coated Wall Surface Temperature in an Engine
Authors: Koutsakis G. , Ghandhi J.B.
Published: April 2020

Thermal swing coatings that have low volumetric heat capacity and low thermal conductivity are attractive because they have the potential to significantly reduce heat transfer to the combustion chamber walls. This paper presents an analytical method for determining the exact solution of the time-resolved wall temperature during the engine cycle for any number of coating layers and properties using the Laplace transformed heat diffusion equation. The method relies only on material properties and the past heat flux history, and represents the exact solution of the heat diffusion equation. The analytical nature of the solution enables fast computation and, therefore, application to system-level optimization calculations. The model relies on an assumption of one-dimensional heat flow, and constant material properties. The major advantage of this approach compared to the standard finite difference approach, wherein the wall is finely discretized, is that there is no approximation and the accuracy is guaranteed, i.e., it does not depend on nodal density. Results are presented for both a quasi-steady operating condition and for an engine transient event. In the latter case a 200-fold reduction in computation time relative to a finite difference code was realized.
Conjugate Heat Transfer CFD Analysis of an Oil Cooled Automotive Electrical Motor
Authors: Srinivasan Chiranth , Yang Xiaofeng , Schlautman Jeff , Wang Deming , Gangaraj Srihari
Published: April 2020

This study brings to forefront the analysis capability of CFD for the oil-cooling of an Electric-Motor (E-Motor) powering an automobile. With the rapid increase in electrically powered vehicle, there is an increasing need in the CFD modeling community to perform virtual simulations of the E-Motors to determine the viability of the designs and their performance capabilities. The thermal predictions are extremely vital as they have tremendous impact on the design, spacing and sizes of these motors. In this paper, with the Simerics, Inc. software, Simerics-MP+®, a complete three dimensional CFD with conjugate heat transfer CHT model of an Electric Motor, including all the important parts like the windings, rotor and stator laminate, endrings etc. is created. The multiphase Volume of Fluid (VOF) approach is used to model the oil flow inside this motor. Two parts of the oil flow, rotor and stator flow, both are simulated, and the net effect of the oil cooling the different solid components is predicted. The study shows the mesh capturing of complicated, intricate paths with relative ease combined with the robust high fidelity interface capturing VOF scheme with rapid turnaround times makes it a very attractive tool for design studies. Thermal results obtained from simulations are compared to physical test data obtained from thermocouple measurements and very good agreement is found.
Balancing Lifecycle Sustainment Cost with Value of Information during Design Phase
Authors: Kassoumeh Sam , Majcher Monica , Ealy James , Gorsich David , Jayakumar Paramsothy , Pandey Vijitashwa
Published: April 2020

The complete lifecycle of complex systems, such as ground vehicles, consists of multiple phases including design, manufacturing, operation and sustainment (O&S) and finally disposal. For many systems, the majority of the lifecycle costs are incurred during the operation and sustainment phase, specifically in the form of uncertain maintenance costs. Testing and analysis during the design phase, including reliability and supportability analysis, can have a major influence on costs during the O&S phase. However, the cost of the analysis itself must be reconciled with the expected benefits of the reduction in uncertainty. In this paper, we quantify the value of performing the tests and analyses in the design phase by treating it as imperfect information obtained to better estimate uncertain maintenance costs. A multi-attribute decision framework for military ground vehicles acquisition is employed to illustrate the methodology and the value of performing the analysis early in the system’s lifecycle. Attributes considered are maintenance cost and operational availability, while the utility is calculated for a risk averse decision maker. Numerical methods are employed to calculate the value of sample information and reflect an increase in expected utility (EU) after collecting the information. While less than the value of perfect information that completely eliminates outcome uncertainty, results demonstrate a positive value for testing. This value determines the maximum amount that should be spent on testing given the anticipated benefits.
Lightweight Design of Automotive Front End Material-Structure Based on Frontal Collision
Authors: ZHANG JIANGFAN , Zou Xiaojun , Yuan Liu-kai , Zhang Hualin
Published: April 2020

The front end structure is an important role in protecting the vehicle and passengers from harm during the collision. Increasing its protective capacity can be achieved by increasing the thickness or replacing high-strength materials. Most of the current research is analyzed separately from these two aspects. This paper proposes a multi-objective optimization method based on weighting factor analysis, which combines material and thickness selection. Firstly, the optimized components are determined based on the 100% frontal collision simulation results. Secondly, six thicknesses and two materials of the front part of the vehicle body are selected as design variables to construct an orthogonal test design. In this paper, a weight-based multi-factor optimization method is used to numerically analyze the response results obtained by orthogonal experiments. Analyze the impact of each factor on the optimization goal to select the most reliable optimization. This optimization method can select the best material and component thickness combination scheme. The results show that the mass of the selected parts are reduced by 16.5%; the total energy absorption is increased by 5.2%; the intrusion in the dash is reduced by 8.9%; and the peak acceleration of the B-pillar is reduced by 39.2%.The material-structure integration optimization method is an effective method to solve the contradiction between lightweight and crashworthiness.
Evaluations of Mechanical Properties of ABS Parts from Open-Source 3D Printers and Conventional Manufacturing
Authors: Garcia Jordan , Harper Robert , Bradley Coilin , Schmidt John , Lu Y Charles
Published: April 2020

3D printing is a revolutionary manufacturing method that allows the productions of engineering parts almost directly from modeling software on a computer. With 3D printing technology, future manufacturing could become vastly efficient. However, the procedures used in 3D printing differ substantially among the printers and from those used in conventional manufacturing. The objective of the present work was to comprehensively evaluate the mechanical properties of engineering products fabricated by 3D printing and conventional manufacturing. Three open-source 3D printers, i.e., the Flash Forge Dreamer, the Tevo Tornado, and the Prusa, were used to fabricate the identical parts out of the same material (acrylonitrile butadiene styrene). The parts were printed at various positions on the printer platforms and then tested in bending. Results indicate that there exist substantial differences in mechanical responses among the parts by different 3D printers. Specimens from the Prusa printer exhibit the best elastic properties while specimens from the Flash Forge printer exhibit the greatest post-yield responses. There further exist noticeable variations in mechanical properties among the parts that were fabricated by the same printer. Depending on the positions that the parts were placed on a printer platform, the properties of resultant parts can vary greatly. For comparison, identical parts were fabricated using a conventional manufacturing method, i.e., compression molding. Results show that compression molded parts exhibit more robust and more homogeneous properties than those from 3D printing.
An Investigation of Real-Gas and Multiphase Effects on Multicomponent Diesel Sprays
Authors: Perini Federico , Busch Stephen , Reitz Rolf
Published: April 2020

Lagrangian spray modeling represents a critical boundary condition for multidimensional simulations of in-cylinder flow structure, mixture formation and combustion in internal combustion engines. Segregated models for injection, breakup, collision and vaporization are usually employed to pass appropriate momentum, mass, and energy source terms to the gas-phase solver. Careful calibration of each sub-model generally produces appropriate results. Yet, the predictiveness of this modeling approach has been questioned by recent experimental observations, which showed that at trans- and super-critical conditions relevant to diesel injection, classical atomization and vaporization behavior is replaced by a mixing-controlled phase transition process of a dense fluid. In this work, we assessed the shortcomings of classical spray modeling with respect to real-gas and phase-change behavior, employing a multicomponent phase equilibrium solver and liquid-jet theory. A Peng-Robinson Equation of State (PR-EoS) model was implemented, and EoS-neutral thermodynamics derivatives were introduced in the FRESCO CFD platform turbulent NS solver. A phase equilibrium solver based on Gibbs free energy minimization was implemented to test phase stability and to compute phase equilibrium. Zero-dimensional flash calculations were employed to validate the solver with single- and multi-component fuels, at conditions relevant to diesel injection. The validation showed that 2-phase mixture temperature in the jet core can deviate up to 40K from the single-phase solution. Surface equilibrium with Raoult’s law employed for drop vaporization calculation was observed to deviate up to 100% from the actual multiphase real-gas behavior. Liquid-jet spray structure in high pressure fuel injection CFD calculations was modeled using an equilibrium-phase (EP) Lagrangian injection model, where liquid fuel mass is released to the Eulerian liquid phase, assuming phase-equilibrium in every cell. Comparison to state-of-the-art modeling featuring KH-RT breakup and multicomponent fuel vaporization highlighted the superior predictive capabilities of the EP model in capturing liquid spray structure at several conditions with limited calibration efforts.
Ramped Versus Square Injection Rate Experiments in a Heavy-Duty Diesel Engine
Authors: Willems Robbert , Willems Frank , Simpson Tony , Albrecht Bogdan , Deen Niels , Somers Bart
Published: April 2020

CO2 regulations on heavy-duty transport are introduced in essentially all markets within the next decade, in most cases in several phases of increasing stringency. To cope with these mandates, developers of engines and related equipment are aiming to break new ground in the fields of combustion, fuel and hardware technologies. In this work, a novel diesel fuel injector, Delphi’s DFI7, is utilized to experimentally investigate and compare the performance of ramped injection rates versus traditional square fueling profiles. The aim is specifically to shift the efficiency and NOx tradeoff to a more favorable position. The design of experiments methodology is used in the tests, along with statistical techniques to analyze the data. Results show that ramped and square rates - after optimization of fueling parameters - produce comparable gross indicated efficiencies. Tests were carried out at 1200 and 1425 rpm; for the latter engine speed peak efficiency was attained at considerably lower NOx levels by applying a ramped injection rate. Particulate matter emissions, on the other hand, are generally lower with the use of square profiles. Heat release analysis further reveals that ignition delays in ramped rate operation are quite long, hinting at vastly different spray behavior. The relatively low loads applied in this work only sustain the delays further. Altogether, this causes the potential of the rate shaping capabilities to be underexploited, as direct control over the burn rate is limited with the combustion system used in this work. The results emphasize the need to carefully select ramp slopes for a particular engine geometry, load and speed point, and additional operating parameter settings.
Fast Catalyst Light-Off with Dynamic Skip Fire
Authors: Luo Xi , Hashemi Sam , Subramanian Ram , Arvanitis Anastasios , Younkins Matthew
Published: April 2020

Catalytic aftertreatment is commonly used to reduce regulated gas emissions from Internal Combustion (IC) engines. Achieving fast catalyst light-off has always been a challenge for automobile IC engine applications. This paper experimentally studied the thermal management and regulated gas emissions from a Spark Ignition (SI) engine with Dynamic Skip Fire (DSF®) technology during cold start period.

The study has found that DSF can increase exhaust gas temperature at the catalyst inlet by up to 100°C, and the exhaust enthalpy by up to 20%. Cold start tailpipe carbon monoxide (CO) and hydrocarbon (HC) emissions can be reduced by 10% to 20% largely due to the increased exhaust gas temperature and enthalpy. Dynamic air pumping can further increase exhaust gas temperature by 30 °C, and can nearly double enthalpy delivered to the catalyst, which reduces cold start HC emissions by more than 50%.
48 V High-power Battery Pack for Mild-Hybrid Electric Powertrains
Authors: Hall Jonathan , Borman Stephen , Hibberd Benjamin , Bassett Michael , Reader Simon , Berger Martin
Published: April 2020

Mild hybridisation, using a 48 V system architecture, offers fuel consumption benefits approaching those achieved using high-voltage systems at a much lower cost. To maximise the benefits from a 48 V mild-hybrid system, it is desirable to recuperate during deceleration events at as high a power level as possible, whilst at the same time having a relatively compact and low cost system. This paper examines the particular requirements of the battery pack for such a mild-hybrid application and discusses the trade-offs between battery power capabilities and possible fuel consumption benefits. The technical challenges and solutions to design a 48 V mild-hybrid battery pack are presented with special attention to cell selection and the thermal management of the whole pack. The resulting battery has been designed to achieve a continuous-power capability of more than 10 kW and a peak-power rating of up to 20 kW. The pack has been built and has been subjected to a series of tests at a range of ambient temperatures. The performance of the pack has been validated and the main characteristics, such as the internal resistance and capacity have also been established. The performance targets for the pack have been achieved. Further testing is underway to fully characterize the pack’s capabilities and characteristics, after which it will be installed into MAHLE’s 48 V eSupercharged demonstrator car.
Multi-Scale Structural Analysis on Rubber Seal for Battery Pack
Authors: Minami Katsuya , Sasaki Takahiro , Sato Takao
Published: April 2020

A rubber sealing for a water-cooled battery pack plays a significant role to prevent water immersion into the inside of the pack. The appropriate design including the adjacent parts achieves a weight reduction of the battery pack by reducing the battery tray thickness and the quantity of bolts used in the whole battery pack.

Generally, finite element analysis (FEA) is effective for the design optimization before proto-typing. However, the application to the sealing for a battery pack requires a large scale analysis, including the complicated contacts and large deformation of the rubber sealing, and results in unpractically long computation time and frequent computation errors due to the finite element distortion.

A multi-scale structural analysis and the process on the rubber sealing for the battery pack has been developed to solve the above issues. This approach consists of 3 steps, which are single-unit, entire-scale and detailed structural analysis.

The cross-section of rubber sealing was simplified as rectangular shape by modifying the mechanical property of the sealing to meet the reaction force characteristic with the original one through the Step 1. Using this simplified model, the entire-scale analysis including the whole battery pack was carried out to extract the area from the entire seal line at which the seal pressure decreases to less than the requirement or high stress of the battery tray and the cover occurs. Then, the detailed structural analysis at the extracted area was carried out for quantitative evaluation.

The developed structural analysis and its work flow can contribute to rubber sealing design optimization by shortening the computation time and reducing the computation errors. In this paper, the developed simulation methodology including the analysis flow are specifically presented. The simulation conditions and results for a battery pack of Battery Electric Vehicle (BEV) are shown as the case study.