bluuebunny/crossref_metadata_2025 huggingface dataset:
Studying and Analysis of crash severity for different Expressways on Al-Rusafa side for Baghdad city using Binary Logistic Regression Model
Authors: Joni Hasan Hamodi , Shallal Mustafa Husham
Published: August 2021

Nowadays, in Iraq, especially Baghdad, many accidents are recorded daily, and the occurrence is different in terms of severity (fatal, injury, property damage only) with different seasons, days and even times, as a result of the anxiety and great concern that these accidents pose on the part of drivers of these highways. Therefore, this study has become necessary to find out the causes which have direct interference with the accident impact on these roads. On the other hand, many researchers in the field of traffic engineering in Iraq didn’t address the severity of accidents on highways. In addition, this study is the first to find out the main causes of accidents for the most important main and vital highways that are used on a daily basis by drivers on the Al- Rusafa side in Baghdad (Mohamed Al-Qasim Expressway, Army Canal expressway). Furthermore, the data utilized in this research consists of a sample size of (236) forms and it was collected from traffic officers for period 2006 to 2019. After analysis by using Logistic Regression Model, there are three variables closely linked to the severity of accidents on Mohamed Al-Qasim Expressway (cause of an accident like (wrong turn, loss of control, closing (safety distance), vehicle body type, speed). Also, and four variables on Army Canal Expressway (road condition, day, vehicle body type, speed) resulting from the Binary Logistic Regression model.
Studying of the effect of many parameters on a bulk liquid membrane and its opposition in Cd(II) removal from wastewater
Authors: Khalaf Zainab Abdulmajeed , Hassan Asrar Abdullah
Published: August 2021

Because of their tendency to accumulate in the body and their highly toxic potential, heavy metal pollution is becoming one of the main problems globally. The presented study examined the likelihood of eliminating heavy metals by means of the Bulk Liquid Membrane (BLM) method, which is a tool of high importance in various applications of such type. BLM is a simple type of liquid membrane which is showing excellent membrane stability yet insignificant solute fluxes. Therefore, this study outlines the BLM’s membrane resistance in removing heavy metals and recovery from the waste-waters. The cadmium (Cd) ions are fully prepared from the acidic aqueous solutions in this study with the use of the BLM. With regard to stirred transfer cell type, an experimental research has examined the recovery and extraction of Cd ions from synthetic wastewater solution via carrier Tri-butyl-phosphate TBP [C12H27O4P] with the use of BLM as an approach of separation. The impact of some parameters such as feed and stripping stirring speed, carrier concentration, membrane stirring speed, initial feed concentration, temperature, feed, and stripping phase pH is assessed for Cd removal. At pH 4 for feed, pH 10 for strip, 10 %(v/v) carrier concentration, 2 ppm initial concentration, 150 rpm,(S:F) = (1:1) in toluene, and the room temperature the maximal efficiency of extraction and stripping of cadmium (II) metal ions was 82 % and 93 %.
Prototype filter design for filter bank multicarrier modulation
Authors: Mohammed Mahmood Jasim , Ali Mohammed Abd Al Kareem
Published: August 2021

The use of the cyclic prefix in the orthogonal frequency division multiplexing (CP-OFDM) system recently it is the technique widely used method in many wireless communication systems, which depends on the use of the rectangular pulse shape for the transmission. However, the use of the rectangular pulse shape in the filter leads to appearance of many problems such as out of band emission and also the necessary need to use what is known as the cyclic prefix for the purpose of preventing interference, which leads to decrease the spectral efficiency due to the exploitation of part of the spectrum for the purpose of protection from interference. For the purpose of getting rid of these problems, the filter bank multicarrier (FBMC)system has been proposed who uses filters to construct the typical pulse that can be used in this system. The main idea in this system is how to choose the appropriate filter system for the FBMC/OQAM because this filter plays a fundamental role in the system. In this research, we will be focused on presenting a new prototype pulse shape that can be used in the fifth-generation networks(5G) of communications and also for the purpose of improving the performance of this system and overcoming the previously mentioned obstacles. During this research we will present two models to form the used pulse model, and then we compare these shapes with the most common pulse shape like (Rectangular, RC, PHYDYAS, Hermite). Through this comparison, the efficiency of these pulses can be determined by studying several different parameters that have a direct impact on performance, such as (BER, SIR, PAPR).
The effect of recycled plastic waste polyethylene terephthalate (PET) on characteristics of cement mortar
Authors: Abed Jasim M , Khaleel Ban A , Aldabagh Inas S , Sor Nadhim Hamah
Published: August 2021

This paper studied the effect of waste Polyethylene Terephthalate (PET) on the workability and mechanical properties of the produced cement based mortar. However, five different waste PET weight fractions of 0, 5, 15, 25 and 50% were replaced with river sand in cement mortar mixtures with constant cement content and water to cement ratio of 525 kg/m3 and 0.48, respectively. The workability of the mixtures is enhanced by increasing the replacement level of plastic waste PET. On the other hand, the dry density, compressive and flexural strengths were reduced as waste PET incorporation increased except the mix contained 5% of PET which improved the compressive and flexural strengths. As a result of the dry density and compressive strength results, it was determined that the mixture containing 25% waste PET is considered as a lightweight mortar and suitable for structural purposes.
Review of ceramic materials that used as a thermal barrier in diesel engine pistons
Authors: Majeed E A , Rashid H K , Hussain M K
Published: August 2021

The diesel engines is used in many industrial applications in addition to that in cars. In this type of engine the fuel-air mixture will burn behind the piston inside the cylinder and will produce high temperature. Developing diesel engines to be more efficient, less fuel consumption, low gas emissions, and high performance that has been pursued for more than two decades. Increased combustion temperature can enhance engine power and efficiency while lowering specific fuel consumption and CO emission rates. Ceramic thermal barrier coatings have been identified as the most promising method for achieving these goals. Due to the abundance of materials and technologies, it is necessary to understand the best material suitable for depositing and the techniques required to complete the process. Many researchers have studied a wide range of materials like ZrO2, Al2O3, mullite, YSZ, and forsterite to develop suitable systems that use thermal barrier coatings. Additionally, many techniques such as EB-PVD and ASP have been developed to meet the requirements of these systems. This paper will examine the materials and technologies that can be used to improve internal diesel engine performance.
A Study of Natural Rosmarinus Corrosion Inhibitor for Zinc In HCl Solution
Authors: Wali Haneen Faleh , Bahar Shaker Salih
Published: August 2021

In this study, the effect of important variables on the corrosion rate of Zinc metal was studied with free corrosion, weight loss, and polarization techniques. The test system was designed to measure corrosion potential, corrosion rate, limited current density, and the polarization technique. The experiment used a 0.1M HCl solution as its medium. Temperatures (20,30, 40, 50, and 60) C and rosemary inhibitor concentrations (1 and 5) g/L were used to study the efficacy of the zinc corrosion process. The results showed that the corrosion rate increased with increasing temperature but decreased with increasing inhibitor concentration in acid solution. The maximum inhibition efficiency in Weight Loss Experiments observed at 5g/L of rosemary and 20 °C is 49.07%. The corrosion potential became more negative with increasing temperature and became nobler (less negative) with increasing inhibitor concentration. It has been shown that rosemary is good as a green inhibitor in acid solution.
Effect of Tungsten additions on Microstructure and Corrosion resistance of F75 alloy.
Authors: Jabr Nuha Hasan , Dawood Nawal Mohammed
Published: August 2021

For many surgical applications such as knee implant, metal-to-metal Hip jointing and denta implants, CoCrMo allays are the main choice. The present study aims to study the effect of Tungsten on Microstructure and Corrosion resistance of CoCrMo (F75) alloy. Tungsten has been added to the base alloy in various weight ratios (0.5, 1 and 1.5 wt. percent). The alloys have been made using powder metallurgywhich has been sintered with two stages at 500°C (2 h) and 850°C (6 h) under Argon atmosphereMicrostructures observation, Corrosion resistance, open circuit potential and Brinell macro-hardness, have been performed. In the microstructure test this phase (CoCr and CoCrMo) was appeared. Corrosion test results have shown that with the addition of (1,5% W) the highest corrosion resistance was found, which gives the lowest rate of corrosion (4.310 mpy) in Ringer’s solution. The hardness of F75 alloy improve after the addition of tungsten in Ringer’s solution, Also hardness increases as tungsten additives increase, which have the highest percentage (1.5%W) gave the highest hardnes
Improved performance of Ti6Al4V alloy in Biomedical applications - Review.
Authors: Haydar H. J. , Al-Deen Jamal , AbidAli Abdulraheem Kadhim , Mahmoud Anasalwjood A.
Published: August 2021

The advantages of Ti6Al4v alloy are high strength, low density, and And the advantage of it being non-toxic and the human body does not reject it. Because of these properties, Ti6Al4v are distinguished by their unique properties. To manufacture high strength and lightweight components for biomedical applications, Ti6Al4v alloy is suitable for purpose because of its properties necessary for manufacture. The properties of TiAl4v alloy about its mechanical properties, its corrosion resistance, wear testing, biocompatibility, and bone fusion in biomedical applications, are discussed in the paper. Although TiAl4v alloy has desirable properties, studies have proven to release the two elements of aluminum and vanadium. These two elements are toxic and affect the biocompatibility of Ti6Al4v despite its unique properties. To avoid that, researchers are looking for a way to solve the problem by addition alloy elements that are less toxic and have good mechanical properties. Examples of these elements are zirconium and tantalum..
Investigation Quantum Electronic Transition of Organometallic Molecules
Authors: Abbas Ibrahim Obayes M. , Al-Robayi Enas M. , Al-Owaedi Oday A.
Published: August 2021

We provide a brief overview of recent calculations and predictions of electronic properties for single-molecules and discuss some principles underpinning strategies for enhancing their electronic performance. Quantum interference effects in the electronic properties of (Pyridine-2Cyclopentene Metallic) organometallic-type molecules possessing four aromatic rings were investigate theoretically. In this paper, electronic transmission properties were study for different types of organometallic molecules. A calculation also provides a powerful tool to estimate the electrical and electronic properties. Furthermore, to probe the electronic structure of all compounds in this study we compute the UV-visible, iso-surface and energies calculations. It is finding that the (HOMO and LUMO) energy changing with replace metallic atoms as well as the energy gap changes as the metal different. Therefore, this indicates the energies depend on the type of the metallic atoms in the studied molecules. All calculations were performed using density functional theory at three parameters with the Lee-Yang-Parr functional (B3 LYP) levels with SDD basis sets.
An insight on the response of foundations resting on sand with geosynthetic materials as a reinforcement
Authors: Alali Manal , Paikaray Bandita , Mohapatra Benu
Published: August 2021

Application of Geosynthetic to resolve several geotechnical engineering problems is widely accepted and effective methods. It improved the foundation’s bearing ability as well as minimizes the settlements associate to footings resting on weak soils. Their use is not only restricted to footings in fact they are widely used in improving the subgrade performance of the pavement sand for slope stabilizations. Over the past few decades numerous researchers have contributed their valuable results based on laboratory tests or numerical investigations. The present study aims to provide a detailed literature survey of research work associated with soil reinforcements together under a common hood which can help the upcoming researchers to understand the work done in this field simply and effectively. It also aims to highlight the effect of depth of geosynthetics, their respective width, relative density of sand or other geo-parameters and layers’ number provided with geosynthetic affect the bearing capability and settlement behavior of reinforced and unreinforced soil structures.
A New Suppression approach of FWM Crosstalk Effect in Optical Communication Link based on Polarization combiner Method
Authors: Mohammed Nidhal A. , Abd Haider J.
Published: August 2021

To meet the growing needs of internet data, optical communication systems have become the backbone of modern communications networks. At the present time, the dense wavelength division multiplexing (DWDM) technique has been used to increase the number of channels, but the nonlinear effects have a great impact that limits the performance of doubling the DWDM system. The four wave mixing (FWM) is the most harmful and dangerous as the effect of FWM increases on the system the greater the optical connection distances. The new approach of pairing groups of different optical signals was investigated to suppress the FWM effect. The simulation was conducted for an 8-channel system with a total data rate (80Gb/s). A comparative study was conducted on the suppression of FWM by the difference in the power inputs (-0.5 to 20) dBm. The robustness of the proposed technique was examined using two forms of modulation (Carrier Suppressed Return to Zero (CSRZ) and Duo Binary Modulation class -1(DBM-1)) techniques, with optical fiber system of (1,2,5) spans, each of length 60 Km, with spacing between the channels 50GHz. The power of FWM was significantly reduced with the CSRZ & DBM-1 techniques to less than (47.97%, 41.38 %) respectively, at an input power of 12.5 dBm. The performance of the proposed system with the polarization technique was improved by the rate of the quality factor (Q-factor of (91.59%, 78.67%) for the same sequence of modulation.
Numerical analysis of a zoned earth dam considering hydrodynamic force during the earthquake excitation
Authors: Jawad Areej A. , Hassan Waqed H. , Fattah Mohammed Y.
Published: August 2021

This paper presents finite element analysis of a zoned earth dam considering hydrodynamic force during the earthquake. Geostudio software using the sub-program SEEP/W and QUAKE/W was used. The earthquake that is used in this analysis are Iraqi earthquake that happened in Ali Al-Garbi within Missan governorate and El-Centro earthquake. Haditha dam section was used for the hypothetical dam. The maximum height of the dam is 57 m. The shell was constructed from the mix of sand-gravel with the average particles diameter range from (0.24 to 16.7 mm). Three different properties were used for core material, each one of these properties was analyzed under three different heads of water in the upstream side. The main parameters that have the influence on the analysis results are; water level in the upstream side of the dam, intensity of the earthquake, properties of the core material, and the value of hydrodynamic force. The hydraulic flux and peak displacement increase with increasing these parameters.
Re-distributing the field outlets for irrigation networks within the new growth cities: The Central District of Kerbala city as example
Authors: Al-Fawzy Ali Mekki , Hasan Isra’a Abdul-Sahib , Hasan Hayfaa Kareem , Hussein Najm Najm Abdul
Published: August 2021

Generally, the rivers in both the natural and lined form use the open-section system to carry water, either for distribution or conveyance purposes. With time and depreciation effect, this system needs to be change or modify to become more indirectly suitable with growth of cities, and specially with transformation of land use from agricultural to residential. The present paper aims to reach a proper decision to re-distribute the field outlets for a part of AliHneidiyah river in Karbala city, Republic of Iraq, for the distance between stations (0+000) and (4+000), to choose between keeping up the current number of outlets or reduce them to a certain, actually used one. For this study, the cadastral maps were used as a reference to determine the agricultural areas served by the river during its route within the study area, and geographic information system to monitor the change in the nature of these areas represented by gradual transformation from agricultural to residential purpose, by using of satellite images for four different years, 2002, 2007, 2013, and 2016. The results of this study showed a great reduction in the agricultural areas on both sides of the chosen length of river route by a percentage of 88%, which leads to change location and specifications of the remain, actually used outlets. In addition, use the whole section for conveyance purposes to protect the water quality. This study showed that the geographic information system is a good and helpful technique for evaluation and make decisions of water related subjects.
Land covers monitoring for Bahar-Al-Najaf (Iraq) based on sentinel-2 imagery
Authors: Al-Helaly Mustafa Hasan , Alwan I. A. , Al-Hameedawi Amjed Naser
Published: August 2021

the last four years have seen a remarkable rise in water levels to the Bahar-Al- Najaf, which led to some areas adjacent to the Al-Bahar region. This creates a state of confusion in the subject of future planning for land uses within the study area. To examine this problem in practice, the images of the Sentinel-2 satellite (within the period 2016-2020) were selected. The resulted thematic maps included six classes of land use and land cover LULC, these classes are (agricultural areas, built up areas, gypsum soil, clay soil, sandy soil, and water areas). With regard to the accuracy of the performed classification process, the so-called confusion matrix indicates that the overall classification accuracy is about 85%. The study concluded that some of the important land use, both the road pilgrimage, the strategic line and its oil transfer accessories had been overwhelmed by water, as well as water approaches a newly built residential complex near the Bahar Al- Najaf. It is imposed by the study; the federal and local government agencies must take rapid measures and procedures to avoid potential future flood risk.
Investigation soil degradation in Iraq by using geomatics techniques
Authors: Dalhel Fadhaa Turkey , Albayati Muthanna M. , Ziboon Abdulrazak T.
Published: August 2021

In this study Remote Sensing techniques have been used to investigate soil degradation in Iraq (alluvial plain) for the period (1976 - 2020) by using different many source of data such as satellite images (Landsat 1-5 MSS C1 Level, Landsat 4-5 TM C1 Level-1, Landsat 7, Landsat 8, and sentinel 2) and use more than one software like (ENVI 5.3, ERDAS Imagine 2015, Arc GIS 10.7, and Blender). This study focusing on determine the main degraded areas in Iraq, (alluvial plain) chosen because of spread sand dunes. To make the study soberer, ground trothing achieved to verify the real status of the area and collect the data by field visit. Bands G, B, R, and IR from LANDSAT-3 in 1976, 1996 and 2014, the same bands used from Sentinel-2 dated 2021. Unsupervised classification made for images of 1976 and 1996 then supervised classification did for images in 2014 and 2021. The classification was carried out using ERDAS Imagine V.2015 software and areas of the main land uses in the study area were calculated. The results indicate that there is a big problem in the base year 1976, this problem almost disappeared in the second station of work 1996, but it returned back after that through the results for the years 2014 and 2021.
Assessment of load capacity of piles and conclusion of a new criterion using static load tests
Authors: Hussein H. H.
Published: August 2021

In this study, a comprehensive evaluation of 27 field tests carried out on different piles driven in various parts of Iraq. This evaluation is made in terms of the pile bearing capacity of each pile, using nine methods. These methods are (Davison offset limit, Chin konder, Brinch Hansen 80%, Brinch Hansen 90%, De court, De Beer, Vander Veen, Fuller&Hoy and Butler&Hoy). The evaluation has shown that De Beer, Chin kondeer, and Vanderveen methods are the best methods because the maximum bearing capacity obtained by these methods is associated with a low pile settlement, although Vander Veen method is time-consuming. Fuller&Hoy and Davison methods are very close and give good results, the maximum bearing capacity obtained by these two methods give high pile settlement, leading to structure failure, especially for structures subjected to loading and unloading. Brinch Hansen 90% and Butler&Hoy methods are suitable methods because they give a good and acceptable bearing capacity with very small pile settlement. As for Brinch Hansen 80% and De Beer methods, they provide high bearing capacity than the failure load. They can be used by multiplying the resulting values by 0.85 to get the maximum bearing capacity of the pile. The study shows that the ratio of 10% after comparing it with results is a bit exaggerating, and 4% of pile diameter can be used as a criterion to find the ultimate load.
Flexural Behavior of Concrete Beams Reinforced with Hybridization Rebars
Authors: Al-Bahrany Barakat Shakir , Alkhudery Hayder H.
Published: August 2021

Flexural behavior of concrete beams reinforced with hybridization steel rebar enclosed by CFRP sheet has been explored in this paper. Seven specimens have been casted and tested under two-point load, one served as a control beam which was reinforced by ordinary steel bars, and six beams were reinforced with hybrid steel bar/sheet CFRP. Two main parameters have been considered which were the length of the hybrid steel bar/sheet CFRP and layers of carbon sheet warping steel bar. The response has been investigated in terms of failure modes, ultimate load, first cracking load, maximum deflection, crack patterns, load-deflection curves. The experimental results indicated that hybrid steel bar/sheet CFRP techniques yielded the same behavior as the control beams and reduced the maximum deflection. Also, it is improved the load capacity by about (4.35% to 42.61%) in comparison with reference beam. Effective reduction of maximum deflection was indicated throughout behavior of all enhanced specimens while no change was recorded in first cracking load in comparison with control specimen. Hybridization length (1200 mm) which represent two-thirds of beam length gives an optimal length of strengthening for one and two layers in terms of ultimate load by 21.74% and 39.13% compared to control beam, respectively.
Improvement shear properties of HMA using crumb rubber with different filler
Authors: Allateef Eman Abd , Abd Ali Abd Alhaq Hadi
Published: August 2021

Rutting is one of the big problems in hot-mix asphalt (HMA) pavements. The primary mechanism of HMA rutting is shear deformation, often caused by high stress in HMA layers during traffic loading, especially at high temperatures. Current HMA rutting tests are not necessarily designed to capture HMA shear properties such as shear strength, shear strain, and shear module. The present work explores the behavior of the shear strength properties of HMA modified with Crumb Tire Rubber (CTR) and two types of filler (brick and lime dust in comparison with passing sieving No.200 as control filler) by developing a Simple Punching Shear Test (SPST) under control of temperature and loading rate. A series of laboratory sample tests to formulate and set up the SPST protocol and the related test parameters, derive the SPST results from the analysis sample to capture the HMA shear parameters from the results, and comparatively evaluate the shear properties of HMA mixes. Results have shown that the SPST is relatively receptive to the form of modifier and filler. Using limestone dust as with (5%) CTR content increased higher shear strength, the rate of increase was about (44.44%) and (51.38%). Also 5% to 7% CTR content with lime dust filler lowering shear strain more than for brick dust filler.
Structural performance of a steel tower model under seismic loading
Authors: Adnan Muaid , Al-Wazni Saad
Published: August 2021

This research represents the dynamic behavior of the steel tower structural model due to applying seismic load. The 3D finite element model is created using ANSYS-software to simulate the real structure used in experiment. The dynamic properties, natural frequencies and mode shapes, are extracted and compared with the experimental model values. The comparison is implemented to verify the FE analysis procedure of the tower model with experimental model results and they are accepted by 83% tuning ratio. The nonlinear seismic analysis is applied to the structural model using observed ground motion in 1999 Turkey Earthquake. The seismic load is applied in two cases; the first is in the x-direction of the structural tower model and the other in the y-direction of the model in a horizontal plane. The maximum response displacements in x and y-axis and load displacement hysteresis for both loading cases are exhibited. The results display that the tower structural model failed with large response displacement in the first few time of ground motion according to IBC-2018 and NBCC-2005. The collapse of the tower structural model occurred after time 18 sec and the applied seismic loading in x-axis has significant effect.
Trip attraction model of selected zones in Baghdad city
Authors: Majeed N H , Qasim G J
Published: August 2021

The initiation of this analysis is to establish a mathematical model for predicting trip attraction for Bab al-moadam sector in Baghdad city that involving land use features. To achieve the study objective, the study area is divided into two zones. A conversation mechanism has been adopted to collect data. The data collection included all education centers, state institutions, shopping centers, and health centers, and their numbers were 21 educational centers, 10 centers belonging to state institutions, 5 shopping centers, 12 health centers. The trip attraction models for six purposes of trips(Educational, state institution, shopping, health, other trips, and the total trips) have been developed. These models have been built when the gathered data was fed to the (spss) software version 22 by using stepwise regression process. The results show that the attraction of trips is highly related to the number and diversity of vital centers in the region. we conclude from this study that educational trips depend on the number of students. Work t rips depend on the number of employees. The number of stores is the most influencing factor on shopping trips. Health trips depend largely on the number of beds in addition to the number of patients in consulting clinics and emergency clinics. Other trips are it depends on other health trips, other educational trips and other work trips, the number of total trips that are attracted to the study area depend on the number of employees, the number of health staff, the number of visitor, and the number of students.
Sustainability of using reclaimed asphalt pavement: based-reviewed evidence
Authors: Enieb M , Hasan Al-Jumaili Mohammed Abbas , Eedan Al-Jameel Hamid Athab , Eltwati A S
Published: August 2021

The concept of sustainability is considered essential in the development of the asphalt mixtures industry, due to its economic and environmental benefits. This study attempts to highlight the potential benefits of sustainability using Reclaimed Asphalt Pavement (RAP). It reviews previous studies conducted on RAP to obtain the most important characteristics in how to use the optimal content of RAP and its effect on some basic properties such as resilient modulus, susceptibility to moisture, permanent deformation, and fatigue. This study mainly focuses on the advantages of using RAP materials in hot mix asphalt (HMA). The results indicated that adding 30% of RAP to virgin asphalt mixtures gives the best performance in terms of the most studied characteristics.
The Use of Geographic Information System to Analyze Stations Locating for Proposed Rapid Bus Route in AL KUT City.
Authors: Balket Shaymaa F. , Asmael Noor M.
Published: August 2021

Bus Rapid Transit (BRT) It is one of the public vehicle systems in modern cities that provides fast, convenient, and cost-saving transport services. It operates on separate lines. The activation of the BRT system depends on the locations of the stations within its route. If the stations were located in suitable locations, it would attract a large number of passengers, this contributes to an increase in the use of public transport and thus reduces traffic congestion, road accidents and environmental pollution in the city. In this research, station locations for the proposed BRT route in Al Kut city will be studied and analyzed. 10 candidate sites were selected for BRT stations. Criteria that were used to analyze the sites of these stations are the locations of government institutions, health and educational services, stopping points for current means of transportation, and the population density of city areas. Geographical Information Systems (GIS) technology was used to represent these criteria spatially on the map to be processed and prepared for analysis using the Services Coverage Tool (Service Area) and allocation Tool (Allocation – Location) available in the network analysis toolbar and overlay tool (intersect) in the Toolbox menu. The results of the analysis showed that the sites of (10) BRT stations are within good and reasonable services coverage areas in relation to the services distribution sites in the city and the BRT route site, as the stations cover (76) government site, (69) educational institutions, (10) health sites, and (11) stops for the current transportation lines. The results of the statistical analysis also showed that the coverage of BRT stations is 88% of the total population density in the city.
Effect of reinforcing materials on mechanical properties of composite material using Taguchi method
Authors: Owaid Anmar Abdulazeez , Kaygusuz Hakan , Mohammed Farag Mahel
Published: August 2021

The mechanical properties play an important role in the selection of suitable material in the manufacturing of boats. In this paper, the effect of glass fiber orientations and the fillers weight fraction on the mechanical properties of un saturated polyester composite material were studied. The glass fibers were used with (0/0, 0/90, 45/45) angles. The carbon filler used with (2.5%, 5%, 7.5%), while the aluminium oxide nano be used with (0%, 1%, 3%) weight fraction respectively. The standard Taguchi’s array L9 (33) was used. The signal to noise ratio and analysis of variance were introduced to analyze and estimate the optimal combination parameters. The results show that the mechanical properties improved with using the reinforcements. The glass fibers orientations angle presents the most parameter effect than the other parameters on the modulus of elasticity, tensile strength and impact strength with a contribution of 81.8%, 83.39% and 96.75% respectively. Followed by carbon and aluminium oxide nano. The optimum parameter with their levels for the highest modulus of elasticity was obtained at (0/90 fiber orientation, 5% carbon and 0% nano aluminium oxide). While the highest tensile strength and impact strength present with using (0/0 fiber orientation and 5% carbon). The experimental and expected results are very close, with an error ratio not exceeding 5%.
Modified Bridgeless Landsman Converter Fed EV Battery Charger with Improved Power Factor
Authors: Dinesh M. , Bhaskar K.B.
Published: August 2021

This research work focuses on the design and construction of a novel Battery-powered Electric Vehicle (BpEV) and to enhance the power-factor of the input AC. This is accomplished by substituting the prevalent diode converter with a newer, high-quality Landsman converter that is equipped with power-factor tuning. The Flyback-isolated and PFC converters work together to let the EV battery to switch between constant current and constant voltage modes. The recommended PFC converter is regulated using a single entity to attain consistent DC-link voltage and to boost the power-factor close to unity, with simulation carried out using MATLAB. As per the findings, a minimum of 60V DC output is required for charging the battery and suppressing input harmonics. In comparison to the usual architecture, the suggested scheme could provide increased power quality, very little device stress, less ripple at both input and output, and significantly lower harmonics. To validate the simulation results, a prototype is developed and deployed to charge a 48V EV battery with a rating of 100Ah in order to make it compliant with the IEC 61000-3-2 standard, particularly in the case of high voltage spikes at the input. The charger’s performance has been deemed to be good in all conditions based on matlab simulation results.
Synthesis and characterization of flower-like Al2O3:C for optically stimulated luminescence (OSL) dosimeter
Authors: Chobpattana Varistha , Chutimasakul Threeraphat , Rungpin Nittima , Rattanarungruangchai Natch , Assavajamroon Ploy , Kwamman Tanagorn
Published: August 2021

Growth in radiation diagnosis and therapy drives personal radiation dosimeters for physical and radiological protection control. Nevertheless, OSL (optically stimulated luminescence) personal dosimeters in Thailand are all imported. In this work, the particulate and flower-like structure of carbon-doped alpha aluminum oxide polycrystal (α-Al2O3:C) with the various carbon dopants (0.1% and 1 %) were studied as a detector in the OSL personal dosimeter. The particulate powder was prepared by alumina powder (295 nm). The flower-like structure α-Al2O3:C was prepared by boehmite precursors, synthesizing from aluminum sulfate via the low-cost and low-temperature hydrothermal method and sucrose as carbon sources. The crystalline structure was identified by x-ray diffraction (XRD). The chemical properties and oxygen vacancies were investigated by Fourier-transform infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS). The size of as-prepared flower-like structure α-Al2O3: C was 2–3 μm confirmed by scanning electron microscopy (SEM). The alumina precursors and carbon dopants affected electron trapping states, morphologies, and OSL outputs. This finding successfully proved that the flower-like α-Al2O3 derived from boehmite precursor exhibits excellent OSL sensitivities to beta irradiation (better than that of the particulate power of α-Al2O3: C) and responded linearly in the range of 0–80 kGy.
US national academy expels astronomer Geoff Marcy
Authors: Gwynne Peter
Published: August 2021

The National Academy of Sciences (NAS) has rescinded the membership of exoplanetary astronomer Geoffrey Marcy. The action, which took effect on 24 May, comes six years after Marcy stepped down from his position at the University of California, Berkeley, for what he called “unwelcome behaviour with female graduate and undergraduate students”.
Call for alternative to medical radioactive treatments
Authors: Gwynne Peter
Published: August 2021

The US Nuclear Regulatory Commission (NRC) must overhaul its system used to categorize and regulate radioactive materials to adequately protect society from their use.
A cosmic adventure
Authors: de Régules Sergio
Published: August 2021

Nobel laureate and cosmologist James Peebles from Princeton University talks to Sergio de Régules about winning the prize, cosmological models and his new book
A welcome reminder
Authors: Durrani Matin
Published: August 2021

A new book about Hawking is a reminder we must make physics welcoming to all
Supercomputers face a cosmic challenge
Authors: Brazil Rachel
Published: August 2021

Fast neutrons from cosmic-ray showers can cause significant errors in supercomputers. But by measuring the scale of the problem, physicists hope not only to make such devices less prone to cosmic corruption but also protect everything from self-driving cars to quantum computers, as Rachel Brazil finds out
How to spark an interest
Authors: Marshall Rick
Published: August 2021

Rick Marshall shares his advice for giving an inspiring and engaging presentation about physics to pre-university school students
Quantum dots/graphene nanohybrids photodetectors: progress and perspective
Authors: Wu Judy , Gong Maogang
Published: August 2021

Semiconductor quantum dots/graphene heterostructure nanohybrids combine the advantages of the enhanced light–matter interaction and spectral tunability of quantum dots (QDs) and high charge mobility in graphene as a charge transport pathway, providing a unique platform for exploration of photodetectors with high performance. In particular, the QDs/graphene nanohybrids allow resolution to the critical issue of charge transport in QDs-only photodetectors stemming from the low charge mobility associated with both QD surface defect states and inter-QD junctions. Furthermore, the achieved capability in industrial-scale fabrication of graphene and colloidal QDs has motivated efforts in research of QDs/graphene nanohybrids focal plane arrays that are expected to be not only high performance and low cost, but also light-weight, flexible and wearable. This paper aims to highlight recent progress made in the research and development of QDs/graphene nanohybrid photodetectors and discuss the challenges remained towards their commercial applications.
A year since George Floyd
Authors: Applewhite Derek A.
Published: August 2021

The murder of George Floyd sparked an awakening, long overdue, which reverberated throughout society. As science begins to acknowledge its role in perpetuating systematic racism, the voices of Black scientists, which have largely been absent, are now being called on. As we rightly begin to make space for diverse voices and perspectives in science, we all must think about what it is we are asking minoritized individuals to do.
A-4 Amyloid Status Modifies the Association between Subjective Cognitive Decline and Brain MRI Metrics
Authors: Steinbach Marilyn J , Khan Omair A , Liu Dandan , Gilbert Camdyn , Thwaites Natalie , Cambronero Francis E , Moore Elizabeth E , Bown Corey W , Acosta Lealani Mae Y , Spirko Katie Osborn , Pechman Kimberly R , Blennow Kaj , Zetterberg Henrik , Hohman Timothy J , Jefferson Angela L , Gifford Katherine A
Published: August 2021

Objective

Subjective cognitive decline (SCD), a potential precursor to Alzheimer’s disease (ad), has been associated with increased neurodegeneration and cerebrovascular disease longitudinally. However, the impact of amyloid status, an early pathological marker of Alzheimer’s disease (ad) on these longitudinal associations is less clear. Here, we related baseline SCD to longitudinal biomarkers of brain health in the context of amyloid status.

Method

Participants included 139 non-demented older adults (72 ± 7 years) from the Vanderbilt Memory & Aging Project who completed a SCD questionnaire and fasting lumbar-puncture to quantify amyloid status (defined using published cutoffs of amyloid-beta42 levels) at baseline. 3 T brain-MRI to measure gray and white matter hyperintensity (WMH) volumes was collected at baseline, 18-months, 3-years, and 5-years. Linear mixed effects models assessed if baseline SCD X amyloid status was associated with longitudinal total and lobar grey and white matter volumes, covarying for baseline age, sex, race/ethnicity, education, diagnosis, mood, and apolipoprotein-Ee4 status. Models were also stratified by baseline amyloid status.

Results

Baseline SCD score and amyloid status interacted with total gray (p = 0.02) and WMH volume (p < 0.05). In stratified models, higher total SCD predicted increased inferior lateral ventricular volume (p < 0.001) among amyloid positive individuals. Conversely, in amyloid negative, greater baseline SCD was associated with increased WMH volumes globally (p = 0.03) and in the frontal and parietal lobes (p-values <0.035).

Conclusion

In the presence of amyloid, the presence of SCD is predictive of neurodegeneration in ad-specific regions. Conversely, SCD without amyloidosis may reflect a cerebrovascular disease, indicated by WMHs. Results highlight how amyloid status may help delineate etiologies of SCD.
A-82 Neurocognitive Improvement after Intra-Arterial Bevacizumab for Steroid-Refractory Radiation Necrosis of the Brain
Authors: Folley Bradley S , Kadner Robert J , Sheehan Jason P , Han Dong Y , Kryscio Richard J , Carter Mary B , Shields Lisa B E , Plato Brian M , La Rocca Renato V , Spalding Aaron C , Yao Tom L , Fraser Justin F , Dashti Shervin R
Published: August 2021

Objective

Evaluate neurocognitive change after single low-dose targeted intra-arterial (IA) bevacizumab in patients with brain radiation necrosis.

Methods

Phase II, single-arm, prospective trial. 10 adults underwent targeted 2.5 mg/kg IA bevacizumab. Neurocognitive indices (Neuropsychological Assessment Battery® and Wechsler Test of Adult Reading) were measured at baseline and 12-months to document performance in 5 domains: Attention, Language, Learning and Memory, Visuospatial, and Executive Function. Clinical indices also quantified. Data (mean ± SD, 95% confidence interval [CI], Cohen’s d) were analyzed using paired t tests. Null hypothesis rejected for p < 0.05.

Results

At baseline, Numbers-&-Letters Speed T-score (38.2 ± 10.7) indicated decreased processing speed consistent with sub-cortical pattern of illness. All other baseline neurocognitive indices were within normalized means (image). 12-months post-treatment, Numbers-&-Letters Errors T-score increased by 6.0 ± 4.9 [95%CI 1.9,10.1] (t = 3.464, d = 1.225, p = 0.010). List-Learning List-Long-Delayed-Recall T-score increased by 9.0 ± 5.6 [95% CI 4.3,13.7] (t = 4.520, d = 1.598, p = 0.003) and Design-Construction T-score increased by 3.5 ± 4.1 [95%CI 0.04,7.0] (t = 2.391, d = 0.845, p = 0.048). Volume of radiation necrosis decreased by 74.4 ± 14.7% (t = −3.308, d = 1.169, p = 0.013). Headache decreased by 84.4 ± 18.2% (t = −3.495, d = 1.236, p = 0.010). 0/10 died or exhibited AEs attributed to bevacizumab. 2/10 patients experienced radiation necrosis recurrence at months 10 and 11, respectively.

Conclusions

Single low-dose intra-arterial targeted bevacizumab led to durable neuropsychological performance increase in memory retrieval and visuospatial ability consistent with improvement in sub-cortical function. To our knowledge this is the first prospective report of this novel approach in adults. Clinical improvements mirrored neuropsychologic improvements. Randomized trials are needed comparing targeted low-dose IA bevacizumab to multi-cycle IV bevacizumab at higher doses to determine which is best alternative in brain radiation necrosis.
A-84 Interdisciplinary Collaboration: Neuropsychology’s Role in Elucidating Neurocognitive Symptoms in a Patient with Arachnoid Cyst
Authors: Yunes Katelyn , Posada Carolina
Published: August 2021

Objective

Arachnoid cysts (ACs) are typically cerebrospinal fluid-filled abnormalities that occur within the central nervous system. ACs are uncommon (prevalence rate of 1.2%), and typically occur within the left hemisphere middle cranial fossa or posterior fossa. Symptoms vary depending on location and size but often include headaches, weakness, cognitive changes, and hydrocephalus. We present an unusual case of a 68-year-old right-handed woman with 13 years of education who was admitted to the hospital following overdose. During a previous admission, Patient was found to have a large arachnoid cystic lesion and right-sided weakness, but was determined not to require acute intervention. Neuropsychology was consulted to assess current cognitive functioning.

Method

Patient was initially diagnosed with a severe major depressive episode with new-onset psychotic features following an overdose of baclofen and Tylenol. Suicide attempt was denied. Magnetic Resonance Imaging (MRI) confirmed previously identified arachnoid cystic lesion (Figure 1) causing mass effect. Patient’s MRI also revealed pituitary macroadenoma (Figure 2) that caused subtle distortion along the optic chiasm.

Results

The results (Table 1) suggested an abnormal cognitive profile characterized by deficits on measures of language, visuoperception, memory, and abstract reasoning in the context of relatively intact auditory attention and working memory.

Conclusions

The extent and severity of Patient’s deficits are likely attributable to the cystic lesion, with recent onset of visual hallucinations likely caused by location of pituitary macroadenoma. This case highlights the importance of having access to a neuropsychological inpatient consultation service to assist with clarification of symptom etiology and facilitation of appropriate diagnosis and intervention.
A-92 Assessing Perceived Workload on the Brief Visual Memory Test in Traumatic Brain Injury Survivors
Authors: Smith Kristina E , Lopez-Hernandez Daniel W , Bueno Alexis , Rugh-Fraser Rachel A , Nordberg Bethany A , Budding Deborah , Hovda David A , McArthur David L , Plurad David , Fuster Joaquin M , Woo Ellen , Hardy David J , Wright Matthew J
Published: August 2021

Objective

We examined perceived workload as it is related to Brief Visual Memory Test-Revised (BVMT-R) short-delay and long-delay performance in traumatic brain injury (TBI) and healthy comparison (HC) participants.

Method

The sample consisted of 39 TBI participants and 54 HC participants. Demographically corrected BVMT-R scores were used to evaluate short-delay and long-delay performances. The perceived workload was measured using the NASA-TLX.

Results

ANOVA revealed that the HC group outperformed the TBI group on the BVMT-R short-delay and long-delay score, p < 05, η p 2 = 0.05. ANCOVAs controlling for age were used to evaluate NASA-TLX group differences. In regards to the NASA-TLX, TBI participants reported higher levels of physical demand, effort, frustration and overall subjective workload on the BVMT-R short-delay compared to HC participants, p < 05, η p 2 = 0.01–0.09. Furthermore, on the long-delay of the BVMT-R, the NASA-TLX revealed that the TBI group reported higher levels of temporal demand, effort, frustration and overall subjective workload compared to the HC group, p < 0.05, η p 2 = 0.05–0.14.

Conclusions

Results revealed that TBI participants demonstrated worse BVMT-R performances than HC participants. However, TBI survivors reported higher perceived workload demands compared to the HC group in both short-delay and long-delay of the BVMT-R. Our findings suggest that TBI impacts non-verbal memory performance in both BVMT-R short-delay and long-delay. Also, brain injury may be impacting TBI survivors’ awareness of their non-verbal memory performance. Further work is required to determine what drives the impaired perception of non-verbal memory performance among TBI survivors.