bluuebunny/crossref_metadata_2025 huggingface dataset:
Procédé technologique LUMELEC : au carrefour de l’optique et de l’électronique
Authors: Arguel P. , Grisolia J. , Launay J. , Tap H. , Capello C. , Rouabhi C. , Guerin F. , Gessinn F.
Published: March 2021

Chaque année, les installations de l’AIME (Atelier Interuniversitaire de Micro-nano-Electronique) de Toulouse sont utilisées par une quarantaine de filières d’enseignement qui y trouvent tous les moyens techniques pour concevoir, réaliser et caractériser un ensemble de dispositifs électroniques ou des microsystèmes électromécaniques. S’inscrivant dans une volonté d’élargissement de l’offre de formation de cette structure inter-établissement, et afin de répondre à une demande croissante de ses utilisateurs, un nouveau procédé technologique visant la conception, la réalisation et la caractérisation de dispositifs optoélectroniques a été mis en place en 2012 et est suivi aujourd’hui par environ 250 étudiants par an, en provenance de diverses formations universitaires ou écoles d’ingénieurs.

Ce procédé, baptisé LUMELEC, a pour objectif de fabriquer, sur un même substrat de silicium, divers photodétecteurs destinés à être caractérisés et dont les performances font l’objet d’une étude comparative en fonction de l’application visée. En rupture avec les approches conventionnelles, nous proposons ici la mise en oeuvre d’une réelle microfabrication par les étudiants, succédant à une phase de modélisation et aboutissant à une caractérisation quasi exhaustive du système réalisé. Ainsi, les contraintes liées à des applications dans des domaines aussi variés que la conversion photovoltaïque, la domotique, la biologie, l’environnement,… sont analysées afin de déterminer les caractéristiques du dispositif le mieux adapté à sa fonction. Aujourd’hui, bénéficiant d’un retour d’expérience sur plusieurs années, nous décrivons dans cet article les principales options retenues pour permettre une mise en oeuvre aisée et « modulaire » de ce projet, et faire en sorte qu’il réponde aux demandes de formations diverses.
Delivering professional doctorate education: challenges and experiences during the COVID-19 pandemic
Authors: Tucker Matthew , Wilson Hannah , Hannibal Claire , Lawless Aileen , Qu Zhouhua
Published: March 2021

Professional Doctorates have similar attributes of a PhD, but are arguably not as universally known. Moreover, professional doctorates have an added level of complexity, as students become scholar-practitioners by ensuring that they make a significant contribution to professional practice. However, professional doctorate education is often challenging due to the lack of research preparedness of professional doctorate students, who typically have been away from higher education for a number of years. Although these students may have built astute business mind sets, it could be argued that their approach to scholarly research is less so. So to achieve engaged scholarship that enables professional doctorate students to become scholar practitioners, it is crucial to create the correct learning environment. Using the Doctorate in Business Administration (DBA) at Liverpool Business School, UK, as a case study, the ability to deliver professional doctorate education is explored, and pertinently the challenge and experience of how the teaching and learning environment has transitioned since the COVID-10 pandemic is evaluated. Finally, key lessons are outlined as to how to design professional doctorate programmes that are resilient to disruptions to conventional teaching and learning practices.
Diagnosing the formation of an environment-oriented component of competencies in higher education
Authors: Ponomariova Olga , Vasina Olga , Shurygin Sergey
Published: March 2021

The article examines the diagnostic tools for evaluating the formation of an environment-oriented component of competencies in students within the system of higher education. The authors present the set of diagnostic tools following their long-term work on identifying the experience of emotional and values-based attitude to nature as the most difficult element of the environment-oriented component of competencies to assess. The article substantiates the selection of diagnostic tools taking into account available environmental knowledge, skills, abilities and behavioural stereotypes of students. It focuses on determining the level of adapted social experience combining the experience of environment-oriented cognitive activity, environment-oriented work methods, environment-oriented creative activity, emotional and values-based attitude. The use of diagnostic tools is illustrated by experimental work within the educational process at A.V. Khrulev Penza Branch of the Military Academy of Logistics and Penza State University.
Implementing innovative teaching methods in the digital environment
Authors: Glotova Tatyana , Kolchugina Irina
Published: March 2021

The article examines the issues of adopting the innovative teaching methods to effectively organise the educational process within blended and distance learning and teaching. The examples of curricula design using modern information technologies and elements (resources and activities) of the digital learning environment of Penza State University are given. The teaching methods and features of their employment are described. The authors highlight the need for further elaborating the issues of ongoing methodological support for teachers in the field of information and pedagogical technologies.
Integrating soft skills development into English language class
Authors: Andrievskikh Svetlana , Lapina Valentina
Published: March 2021

Many employers around the world express their concerns about recent graduates’ lack of necessary soft skills. They claim that new hires are inadequately prepared for handling some of the common challenges which have to be addressed at the workplace and the skills gap is widening with every passing year. Employers are looking for candidates who can understand and analyse ideas, tackle complex issues, actively contribute and take responsibility when working on projects, and are willing to develop their skills and acquire the new ones throughout their careers. Being aware of the problem, the authors undertook a study and propose some suggestions of integrating soft skills development into university English Language class.
Modeling cognitive learning spaces in Russian universities in the context of globalization and digitalization
Authors: Tregubova Tatiana , Ainoutdinova Irina
Published: March 2021

The article is devoted to the modeling cognitive learning spaces in Russian universities for the effective training of students and their preparation for life and future profession. Based on a comparative analysis of theoretical and practical approaches to the problem by Russian and foreign scientists, a conclusion is made about the importance and relevance of the topic for academic community and society as a whole. In modern conditions, the processes of globalization, integration, informatization and digitalization induce universities to change the vector of their activities in the direction of technology and innovation, advanced forms of communication and mental interaction, technological methods of teaching and knowledge transfer, and, as a result, cause them to review their learning spaces as well. From a pedagogical perspective, the design of cognitive learning spaces may equally influence the entire educational landscape of the country as well as the learning climate of a particular institution, learning outcomes of a particular student and the system of professional development of a particular teacher and/ or researcher in multiple ways. The purpose of this work is to study and analyze the current state of the problem, systematize and concretize the conceptual apparatus, identify current positive trends in higher education allowing to model and design the effective tech-based, information-rich and equitable cognitive learning space at university, which will provide a beneficial learning environment with regard to mental needs and expectations of modern students.
An improved Kirkwood–Bethe model for calculating near-field shockwave propagation of underwater explosions
Authors: Zhang Jingxiao , Wang Shushan , Jia Xiyu , Gao Yuan , Ma Feng
Published: March 2021

To calculate the near-field shockwave propagation of underwater explosions for different explosives quickly and accurately, an improved calculation model, based on the Kirkwood–Bethe theory, is proposed. Based on the detonation theory and shock jump conditions, the model establishes initial equilibrium conditions and an initial shockwave-front state of the explosion bubble interface. By incorporating a second-order Mach-precision bubble dynamics equation, the model determines the physical parameters and enthalpy change functions at the initial expanding stage in real time. By solving the isentropic flow of the enthalpy change function G at varying delay times, a functional relation was established between the enthalpy change function and the pressure at arbitrary flow points and times. The model obtained the near-field shockwave-front peak-pressure spatial distributions of underwater explosions and the pressure decay time constants at arbitrary flow points. The results indicated that the proposed method can quickly and accurately determine the near-field shockwave propagation of underwater explosions for different explosives, with satisfactory agreement with experimental data. The proposed method relates the explosive detonation, explosion bubble expansion, and shockwave propagation, thus connecting the explosive parameters with the shockwave front state parameters.
Adsorption of crotonaldehyde on metal surfaces: Cu vs Pt
Authors: Nayakasinghe Mindika Tilan , Guerrero-Sánchez Jonathan , Takeuchi Noboru , Zaera Francisco
Published: March 2021

The thermal chemistry of crotonaldehyde on the surface of a polished polycrystalline copper disk was characterized by temperature-programmed desorption (TPD) and reflection–absorption infrared spectroscopy (RAIRS) and contrasted with previous data obtained on a Pt(111) single crystal substrate. A clear difference in the adsorption mode was identified between the two surfaces, highlighted by the prevalence of RAIRS peaks for the C=C bond on Cu vs for C=O on Pt. Adsorption was also determined to be much weaker on Cu vs Pt, with an adsorption energy on the former ranging from −50 kJ/mol to −65 kJ/mol depending on the surface coverage. The experimental data were complemented by extensive quantum mechanics calculations using density functional theory (DFT) to determine the most stable adsorption configurations on both metals. It was established that crotonaldehyde adsorption on Cu occurs via the oxygen atom in the carbonyl group, in a mono-coordinated fashion, whereas on Pt multi-coordination is preferred, centered around the C=C bond. The contrasting surface adsorption modes seen on these two metals are discussed in terms of the possible relevance to selectivity in single-atom alloy hydrogenation catalysis.
Path-integral calculation of the fourth virial coefficient of helium isotopes
Authors: Garberoglio Giovanni , Harvey Allan H.
Published: March 2021

We use the path-integral Monte Carlo (PIMC) method and state-of-the-art two-body and three-body potentials to calculate the fourth virial coefficients D(T) of 4He and 3He as functions of temperature from 2.6 K to 2000 K. We derive expressions for the contributions of exchange effects due to the bosonic or fermionic nature of the helium isotope; these effects have been omitted from previous calculations. The exchange effects are relatively insignificant for 4He at the temperatures considered, but for 3He, they are necessary for quantitative accuracy below about 4 K. Our results are consistent with previous theoretical work (also with some of the limited and scattered experimental data) for 4He; for 3He, there are no experimental values, and this work provides the first values of D(T) calculated at this level. The uncertainty of the results depends on the statistical uncertainty of the PIMC calculation, the estimated effect of omitting four-body terms in the potential energy, and the uncertainty contribution propagated from the uncertainty of the potentials. At low temperatures, the uncertainty is dominated by the statistical uncertainty of the PIMC calculations, while at high temperatures, the uncertainties related to the three-body potential and omitted higher-order contributions become dominant.
Analytical Hessians for Ewald and particle mesh Ewald electrostatics
Authors: Simmonett Andrew C. , Brooks Bernard R.
Published: March 2021

The particle mesh Ewald (PME) method has become ubiquitous in the molecular simulation community due to its ability to deliver long range electrostatics accurately with ON  ⁡log(N) complexity. Despite this widespread use, spanning more than two decades, second derivatives (Hessians) have not been available. In this work, we describe the theory and implementation of PME Hessians, which have applications in normal mode analysis, characterization of stationary points, phonon dispersion curve calculation, crystal structure prediction, and efficient geometry optimization. We outline an exact strategy that requires O(1) effort for each Hessian element; after discussing the excessive memory requirements of such an approach, we develop an accurate, efficient approximation that is far more tractable on commodity hardware.
Dual-process brain mitochondria isolation preserves function and clarifies protein composition
Authors: Noterman Maria F. , Chaubey Kalyani , Lin-Rahardja Kristi , Rajadhyaksha Anjali M. , Pieper Andrew A. , Taylor Eric B.
Published: March 2021

Significance

The unique aspects of brain mitochondria composition and function are incompletely understood, and new approaches are required to understand their relationship. We addressed this challenge through a dual-process isolation procedure that yields both semipure brain mitochondria suitable for functional studies but not protein localization and ultrapure brain mitochondria that are suitable for determining protein localization but functionally compromised. We observed that contrary to the published literature, N-methyl-D-aspartate receptor, ryanodine receptor 1, glyceraldehyde 3-phosphate dehydrogenase, monocarboxylate transporter 1, excitatory amino acid transporter 1, and the L-type calcium channel Ca
v
1.2α1 subunit are absent from brain mitochondria. Utilization of this dual-process brain mitochondria isolation technique will foster clarity on mechanisms of brain health and disease.
Contamination of argon x-ray spectra by tungsten and other elements commonly found in tokamaks
Authors: Rice J E , Gu M , Cao N M , Hughes J W , Reinke M L , Sertoli M , Vezinet D
Published: March 2021

Emission lines which appear in the spectral ranges of ground state transitions from n = 2 levels in He- and H-like argon ions are discussed. X-ray transitions from elements commonly found in tokamaks (tungsten, molybdenum, iron and sulphur) which radiate in the wavelength range from 3700–4000 mÅ are identified by comparison with atomic structure calculations. Individual lines from tungsten charge states in the vicinity of Zn-like W44+ are documented, along with B-like Mo37+. The behaviour of line ratios as a function of electron temperature is examined, in support of the identifications.
VO2–graphene-integrated hBN-based metasurface for bi-tunable phonon-induced transparency and nearly perfect resonant absorption
Authors: Erçağlar Veysel , Hajian Hodjat , Özbay Ekmel
Published: March 2021

A bi-tunable hexagonal boron nitride (hBN)-based metasurface with bi-functional phonon-induced transparency (PIT) and nearly perfect resonant absorption features in the mid-infrared (MIR) range is proposed. The metasurface, that is composed of axially symmetric hBN rings, is separated from a uniform thin vanadium dioxide (VO2) film with a SiO2 spacing layer and is integrated with a top graphene sheet. For the insulating phase of VO2 (i-VO2), PIT with an 80% transmission contrast ratio is observed inside the reststrahlen (RS) band of hBN due to the support of hyperbolic phonon polaritons. A considerably large group delay of 9.5 ps and up to 1.8 THz RIU−1 frequency shift per refractive index unit is also achieved for the i-VO2 case. On the other hand, it is found that for the metallic phase of VO2 (m-VO2), light transmission is prohibited and nearly perfect resonant absorption peaks are appeared inside the RS band of hBN. Finally, by integrating the hBN-based metasurface into the graphene sheet on the top, a tunable PIT-like effect and nearly perfect light absorption is achieved duo to the hybridization of graphene plasmons and hBN phonons. This leads to a modulation depth as high as 87% in the transmission (i-VO2) and 62% in the absorption (m-VO2) responses. Our findings offer a tunable and bi-functional device that is practical for MIR slow-light, sensing, and thermal emission applications.
Perfect discrimination of quantum measurements using entangled systems
Authors: Datta Chandan , Biswas Tanmoy , Saha Debashis , Augusiak Remigiusz
Published: March 2021

Distinguishing physical processes is one of the fundamental problems in quantum physics. Although distinguishability of quantum preparations and quantum channels have been studied considerably, distinguishability of quantum measurements remains largely unexplored. We investigate the problem of single-shot discrimination of quantum measurements using two strategies, one based on single quantum systems and the other one based on entangled quantum systems. First, we formally define both scenarios. We then construct sets of measurements (including non-projective) in arbitrary finite dimensions that are perfectly distinguishable within the second scenario using quantum entanglement, while not in the one based on single quantum systems. Furthermore, we show that any advantage in measurement discrimination tasks over single systems is a demonstration of Einstein–Podolsky–Rosen ‘quantum steering’. Alongside, we prove that all pure two-qubit entangled states provide an advantage in a measurement discrimination task over one-qubit systems.
The dynamic load test of two seismic resistance of steel structures EBF and RBS
Authors: Rastandi J I , Orientilize M , Ashilah C , Apritasari D
Published: March 2021

The non-destructive dynamic loading test has been conducted on two seismic resistance of steel structures, reduced beam section (RBS) and eccentric braced frame (EBF). Eccentric mass shaker was used to excite the 1-storey 1-bay steel structure. Two dynamics parameters were obtained which were the natural frequency and the damping ratio. A finite element analysis was performed using OpenSees software to get a comparison result. Similar natural frequency and displacement response were obtained from the test and the FE Analysis. The Natural frequency of RBS and EBF was around 3.614 Hz which is similar to the FE analysis as 3,623 Hz. Meanwhile the damping ratio is 3.149%. The natural frequency of the EBF structure is around 6.0 to 6.13 Hz, while the FE analysis result is 6.13 Hz. The damping ratio from test results is between 2.04 – 2.06%.
An Estimation of Electrical Energy Saving for Lecture Building at Universitas Andalas Using Daily Electric Need Pattern
Authors: Akbar F , Pujani V , Juliani E , Nazir R
Published: March 2021

Electrical energy is a mandatory requirement for carrying out various kinds of human activities. Nowadays, electrical energy must be used efficiently, that is, as needed. However, in use, it is often done excessively and inefficiently, which causes energy loss. It has an impact on the high spent on electricity costs. This research was conducted using an analytical method to obtain a pattern of ideal daily energy consumption needs for various kinds of academic activities in the Universitas Andalas lecture building, namely during the lecture period, exam period, and lecture holidays. The ideal pattern of needs is obtained by considering electrical equipment data, lecture schedules, the questionnaire results on electricity users’ behavior, and the value of lighting intensity. The pattern is plotted on a graph every 30 minutes for 24 hours. The pattern results are then compared with current electrical energy usage to evaluate everyday electrical energy use to improve future use. Based on testing the pattern of ideal electrical energy needs with current, it is found that electrical energy is the least efficient during the lecture holidays with a percentage value of 55% to 75%.
Design a Stethoscope Digital to Keep the Medical Practitioner at an Adequate Distance While Examining the Patient
Authors: Rusydi M I , Ningsih E M , Pawawoi A , Nofendra R , Windasari N
Published: March 2021

A stethoscope is an instrument in medicine used to listen to the sounds produced in the body or auscultation, primarily to listen to the sound from the lungs and heartbeat. Medical practitioners usually use the sound from a stethoscope as an indicator to diagnose an illness. Regular stethoscope with earpiece is less effective to use since the novel coronavirus quickly spreading from saliva droplets. Medical practitioners have difficulty attaching the conventional stethoscope to the ear because they have to use personal protective equipment, including head covering, to deal with coronavirus patients and patients with other medical complaints. This research designs a digital stethoscope that can be used even the head of medical practitioners covered by safety clothes. This stethoscope has a sound sensor, OLED, a microprocessor, and a speaker. The sound of lungs and heartbeat from 30 volunteers was recorded to investigate the frequency of noise, lung, and heartbeat. A bandpass filter was designed to get the signal with an upper cut-off frequency of 50 Hz to 80 Hz and a lower cut-off frequency of 5 Hz. The result shows that this stethoscope can detect the number of heartbeats and give a clear lung sound. This device can help medical practitioners examine patients while keeping their distance from patients.
Design the motor acceleration for the desired frequency air volume inspiration of asynchronous mechanical ventilator based on a pressure sensor
Authors: Rusydi M I , Jordan A , Laksono H D , Windasari N , Ngetha H T
Published: March 2021

The SARS-CoV-2, a virus that attacks the respiratory system, has some difficulty breathing and chest pain. A mechanical ventilator is a simple version of a ventilator and most used to support patient breathing because it iseasy to use. This research design a mechanical ventilator operate based on the frequency and air volume of inspiration. The operator can set the ventilator using a potentiometer and choose the menu on an LCD. A couple of press wall push a bag valve mask in the desired frequency. The motor speed has a vital role to perform the number pushing based on the desired setting. The amount of airflow out from this bag depends on the duration and the depth of pushing. Some standard frequencies of human breathing were investigated in the range of 12 to 20 times of inspiration in a minute. The acceleration of the ventilator based on calculation was implemented to the machine, and it reduced the number frequency to 64% of the desired frequency. An error compensator is used to improve the accuracy of the ventilator. It compensates by multiply calculated acceleration by 2.31. It is successfulin improving the performance and resulted in the ventilator work in the desired frequency and volume.
Analysis of Particulate Matter 2.5, carbon monoxide, carbon dioxide, CO/CO2 ratio and rate of fuel consumption from the use of biomass stove fueled by corncob and rice husk
Authors: Goembira F , Putra R W , Ihsan T
Published: March 2021

This study was conducted to analyze PM2.5, CO and CO2 concentrations, CO/CO2 ratio, and the rate of fuel consumption due to the use of a biomass stove. Water Boiling Test Method was used to simulate cooking activities, which consisted of three phases, i.e., cold start (CS), hot start (HS), and simmering (SM). Biomass wastes used in this research were corncobs and rice husks. Based on the measurement results, for the corncob, PM2.5 concentrations were 239.823±60.83, 262.962±79.17, and 120.75±45.20μg/Nm3 at CM, HS, and SM phases, respectively. While for CO concentrations during the CM, HS, and SM phases were 36.984 ±3.67, 35.918±1.74, and 37.959±5.56 ppm, correspondingly. Moreover, 595,468±13.25, 611,492±7.73, and 565,205±18.50 ppm CO2 concentrations were detected during the CM, HS, and SM phases, respectively. Furthermore, for the rice husk biomass waste, PM2.5 concentrations of 158.579±14.07, 115.014±16.08, and 69.603±17.11 μg/Nm3 were observed during the CS, HS, and SM phases. While for CO concentrations during the CS, HS, and SM phases, the measured values were, in turn, 38.152±2.73, 38.152±5.02, and 36.422±4.72 ppm. Lastly, the measured CO2 concentrations were 593,647±8.28, 589,241±12.45, and 556,886±13.06 ppm for the CS, HS, and SM phases, respectively. PM2.5 and CO concentrations did not meet the air quality standards for both biomass wastes, while CO2 meets the air quality standard according to Indonesian Minister of Health Regulation No. 1077/2011. The CO/CO2 ratio of the biomass stove is above 0.02, while the specific fuel consumption rate, for corncob were 0.186, 0.135, and 0.238g/g, while for the rice husk were 0.238, 0.305, and 0.335g/g, during the cold start, hot start, and simmering phases.
An Assessment of Heavy Metals Pollution in the Waters and Sediments of Lake Maninjau, Indonesia
Authors: Komala P S , Nur A , Badriah N L , Harefa M , Silvia S , Ridwan  , Zulkarnaini
Published: March 2021

This research performs an analysis of heavy metals in the waters and sediments of Lake Maninjau and the resultant pollution index value. The research was carried out in 11 locations, e.g., floating net cages, endemic fisheries, near settlements, hydropower plants, and seven rivers at the lake’s inlet and outlet at a depth of 0-1.5 metres. Determining the pollution index was conducted based on heavy metals and environmental parameters. Aside from Zn, the concentration of Cd, Hg, Pb, Cu in the waters in all locations exceeded the quality standard. The Hg metal in sediments in all areas exceeded the quality standard of contaminated soil. Concentrations of heavy metals in sediment are higher than that of heavy metals in water. 8 of 11 sampling locations were in the medium polluted category, with the fish cage location having the highest pollution index (PI) value. Anthropogenic activities such as aquaculture, water transportation, and settlements around the lake have an effect on the waters and sediments of the lake, characterised by heavy metal contamination. The lake’s quality must be continuously monitored, and wastewater management improved from activities around the lake to control heavy metal contamination. Further evaluation is required of the heavy metals contamination originating from anthropogenic activities and natural sources.
Optimizing Inventory Control System of Crumb Rubber Raw Material: a Case Study
Authors: Amrina E , Dewi A Y
Published: March 2021

Rubber companies often face problems with raw material inventory because obtained from nature. To anticipate shortages of inventory, companies usually buy raw materials in excess quantities. This will result in large inventory costs. This study aims to optimize the inventory control system of crumb rubber raw material in a case rubber company. It started with the demand forecasting of crumb rubber raw material. The level strategy method is then used to determine the production planning of crumb rubber. Finally, the fixed order quantity model is applied to determine the optimal inventory control of crumb rubber raw material. The results show the optimal inventory level of crumb rubber raw material is 988,881 Kg, with a reorder point is 526,570 Kg, and a safety stock is 342,302 Kg. It obtained the total inventory cost is IDR 1,843,689,421 per year. Inventory control is useful for ensuring the smooth production process and preventing excess or shortage of inventory. The results are expected can aid the rubber company in improving inventory control and minimize inventory costs.
Applying system dynamic for predicting the strengths, weaknesses, opportunities, and treats of Patchouli Oil Agroindustry in West Sumatra
Authors: Rahmayanti D , Hadiguna R A , Santosa  , Nazir N
Published: March 2021

The patchouli oil agroindustry is one industry that has the potential to be developed in West Sumatera. This study aims to analyze the future condition of the patchouli oil agroindustry in West Sumatera. As an initial step of the formulation strategy for developing patchouli oil agroindustry in West Sumatra. This study conducted a SWOT analysis using a dynamic system approach. The system dynamic is very suitable for the patchouli oil agroindustry’s design development model because of the complex system. Other studies that have been conducted with SWOT analysis uses qualitative data obtained from corporate informants. In this study, SWOT data is collected based on the output derived from the dynamic system model. The system dynamics model run by using Powersim software with graphical output. Graphics can present internal and external conditions and the patchouli oil industry. Graphic trends that tend to increase will be categorized as strengths, while declining trends are classified as weaknesses. Based on the simulation results, there are six strengths, six weaknesses, two opportunities, and three threats of patchouli oil agroindustry forces in West Sumatra.
Effect of changes in the regeneration temperature and the regeneration airflow velocity on the system performance of the solid desiccant air conditioning
Authors: Saputra D A , Osaka Y , Tsujiguchi T , Kodama A
Published: March 2021

This paper presents the effect of changes in operating parameters on the solid desiccant air conditioning system performance. It has consisted of the regeneration temperature and the regeneration airflow velocity parameters. These parameters were examined in two operation modes, the former ranging from 2 m/s–0.83 m/s at constant regeneration temperature, and the latter ranging from 75°C–46.4°C at constant regeneration airflow velocity. The results indicate a smaller decline in dehumidification performance for the constant regeneration temperature operating mode than the constant airflow velocity operating mode. On the contrary, the system performance and the recovery energy ratio at the latter operating mode gives a higher value than the former operating mode. These results suggest that when the dehumidification performance becomes the main function in the system, the regeneration airflow velocity should not be too low to avoid a significant reduction in system performance.
Mechanical Properties and Microstructure of Mg-1.6Gd Alloys Reduction 80% Hot Rolling as Implant Materials
Authors: Susanti O , Rahmadino A
Published: March 2021

Mg-Gd alloys is of great interest for many potential application especially in implant material. Higher mechanical properties is always the goal pursued by reserachers for the materials which generally have relatively still low strength, low ductile and loe hardness. From this aspect, the present paper reviews the recent report of a kind of Mg-Gd rolled which have been able to achieve strength compared with Mg-Gd casting alloys. The aim of this paper is to investigate the mechanical properties and microstructure forMg-Gd alloys that are rolled at high tempetaure with severe reduction. Mg-Gd rolled with 80% reduction will be applied by unidirectional and cross direction with purpose to find varian characteristic. The Temperature range are 400,450,500 and 550°C. The results of this experiment show that the highest hardness number obtained by single rolling specimen as 64.86 VHN at 550 °C. The highest ultimate tensile strength numbers obtained by cross rolling with 163.22 MPa at 550 °C. For the grain size, single rolling specimen has the smallest number with 46.33μm at 500 °C. Overall, temperature 500-550 °C give a big impact to improve Mg-1.6Gd alloys.
Circular Economy Practices by the Informal Sector: an Implementation of Green Manufacturing in Urban Area
Authors: Sutanto A , Yuliandra B
Published: March 2021

A large amount of household e-waste and their recovery activities by the informal sector positively impact the economic, social, and environmental in the urban area because they strongly support sustainable and green manufacturing principles. This research aims to observe the household e-waste collecting model in Padang city, Indonesia. Furthermore, it also wants to find several retain values of the Circular Economy practices by the informal sector for household e-waste when recycled, reused, or remanufactured. The e-waste from the refrigerator, air conditioner, and washing machine is taken as sample cases in this research. The result shows at least two collecting models: the reverse e-waste flow with and without the repair or service shop’s involvement. These models include some actors such as (1) end-users, (2) household collectors, (3) repair shops, (4) intermediary collectors, (5) final collectors, and (6) recycling plants. Most of the collectors and repair shops involved are in the informal sector. The result also shows that remanufacturing through rebuilding its functional status as a new performance by reusing e-waste obtains the highest recovery value. Such remanufactured products in the secondary market can reach up to 40% from their first price. Recycling of household e-waste products has the lowest recovery value. However, copper (Cu) from e-waste products has the highest market value, and it follows aluminum and ferrous metals, among other metals, when recycled or reused.
High Performance Asphalt for Airfield Pavement
Authors: Guyot Xavier
Published: March 2021

Due to the expected increase in air traffic movements around the world and its impact on the environment, the requirement to build more sustainable and low maintenance airfield infrastructures has become very important. One solution consists in using high performance asphalt materials in order to provide a better sustainable whole life cost solution for these pavements. Performances of binder play a key role in the performances of the asphalt pavement as the properties of both are linked. Using Polymer Modified Bitumen Asphalt materials for runway and taxiway represents an alternative solution to traditional Marshall Asphalt (MA). This type of products for wearing course and binder can improve considerably the airfield pavement performances regarding the Rutting resistance, thermal susceptibility or even Fuel resistance. Due to new generation of aircraft more and more aggressive, use of rut resistance asphalt base course is also mandatory. Asphalt Concrete manufactured with Hard Grade bitumen like “High Modulus Asphalt” with improved mechanical characteristics can lead to longer service life, by preserving resources and bringing also cost savings as maintenance is reduced. This type of Asphalt Concrete showed on major airport projects his potential as a viable alternative to the traditional airfield pavement materials for base course such as Crushed Rocks or Dense Bitumen Macadam.
Field Experiment for Accuracy Verification of the Devices Measuring International Roughness Index in TRUE Project: Five Years Report
Authors: Tomiyama K , Nakamura H , Mashito H , Jomoto M , Kameyama S
Published: March 2021

A lot of devices measuring the International Roughness Index (IRI) has recently been developed and applied in response to the pavement inspection purposes. Consequently, the accuracy of measured IRIs obtained with different devices on the same road surface has become a practical concern for providing a consistent inspection result. Against this background, the specified non-profit organization Pavement Diagnosis Researchers Group (PDRG) in Japan has undertaken a project regarding the experiment to harmonize and compare Test methods for surface Roughness Under actual road Environment (TRUE project) since 2014. The TRUE project has so far conducted the roughness measuring experiments three times over five years at Hokkaido, Japan. This paper introduces the features of the TRUE project such as participated devices, test site selection, and data recording and reporting procedures. A benchmark testing for obtaining reference profiles is also provided to make the project reliable. In this paper, the results of experiments conducted in the last five years are statistically described as well. Finally, this paper introduces the potential of the TRUE project such as a new device grouping and the accuracy evaluation report for device certification for contributing to further improvement of a device participated in the project.
Performance study and application of porous ultra-thin wearing course for asphalt pavement maintenance
Authors: Li Mingliang , Lu Haizhu , Li Jun , Mao Quan , Chen Long
Published: March 2021

An ultra-thin layer wearing course with thickness between 15mm and 30mm are developed and applied for maintenance of asphalt pavement. The maximum size of the coarse aggregate is 10 mm. In this study, the high viscosity modified bitumen is used as binder for improving the anti-rutting and raveling performance of a porous mixture. Mixture designed study is carried out by combing the functional and structural performance measurements. The target air voids contents for those ultra-thin surfaces are between 15% and 20%. Important factors presenting the high temperature property, moisture feature, low temperature feature and anti-raveling performance are investigated in lab. Meanwhile, surface characteristic which reflect the sound absorption is also observed. A feasibility of using the ultra-thin wearing course mixture in China is proved. Trial sections are constructed in southeast part of China for studying the performance of ultra-thin waring course in maintenance engineering. The achievements from the study will provide technical support for the maintenance of asphalt pavement with moderate surface damage. It will also improve the skid resistance and the noise reducing function of the old pavement, which presents superior social and environmental benefits.
Design Mixture of RAP-HMA Pavements: A Review
Authors: Sharma A , Ransinchung G D , Kumar P , Kumar D S N V A
Published: March 2021

Roads are the national assets of a country. Once they are non-functional, they can be recycled to serve the next design life. Flexible pavements are the predominant type of pavement all over the world. The distressed flexible pavement material can be termed as Reclaimed Asphalt Pavement (RAP) material. The most common percent of RAP in the recycling process is 20% only. For higher incorporation of RAP material, there is uncertainty in the performance of RAP-HMA mixture. Design Mixture of RAP incorporated HMA technology depends on criteria’s like the viscosity of aged RAP extracted binder, dosages of recycling agents, overheating of RAP material and method of intrusion of RAP material in plant production units etc. The fields cum laboratory studies have found rutting, fatigue and moisture susceptibility as major concerns in this technology. The uses of rejuvenators have been found to improve the fatigue resistance of asphalt mixture but its over-dosages may impact rutting resistance. Hence, a balanced mixture design method which involves performance evaluation of recycled mixture is required. This paper discusses the mixture design of RAP-HMA pavement.
Reviewing methods for determination of Dielectric Constant required to Calibrate GPR Study for Asphalt Layers
Authors: Walia A , Rastogi R , Kumar P , Jain S S
Published: March 2021

Ground Penetrating Radar (GPR) is a non-invasive technique developed substantially in the recent years. Initially, GPR technology was applied to natural ground to explore the sub-surface conditions and identify the anomalies in it. Now it has become a well-accepted technique to investigate any kind of materials such as wood, ice, concrete, asphalt etc. The calibration of GPR equipment is most important prerequisite criteria before data collection for accurate investigation of pavement subsurface features. During calibration, the velocity of radar waves will be calibrated in contrast to subjected material as whole examination is governed on the basis of it. The basic dielectric properties required as a prerequisite while using GPR system are dielectric permittivity, electrical conductivity along with magnetic permeability. The dielectric constant affects the velocity of transmitting wave as inverse proportion i.e. velocity decreases with an increase in dielectric constant and vice-versa. Considering the principle, the detailed study of pavements requires understanding and estimation of ‘bulk’ dielectric constant. The heterogeneous conditions of pavement actually obscure the straightforwardness of analysis and therefore estimation of a ‘bulk’ dielectric constant value becomes essential. There are several methods to compute the dielectric constant of asphaltic layers, which are developed by different researchers, and these are discussed briefly in this paper. The paper tries to put forward the merits and demerits of these methods and to identify the most appropriate one suiting to Indian conditions.
Assessing Health Impact of Air Pollutants in Five Iraqi Cities Using AirQ+ Model
Authors: Abbas T R , Abbas R R
Published: March 2021

Concentration of air pollutants CO, NO2, SO2, O3, PM10, PM2.5 in four Iraqi cities (Al-Najaf, Al-Muthanna, Maysan, Kirkuk) and PM2.5 in Baghdad city were monitored and analysed for the period September 1, 2019 to August 31, 2020. The results showed that the daily mean concentration of CO, NO2for the four cities are well below the WHO air quality standard. In general, PM2.5 and PM10 concentrations are the factors that govern the air quality index in Iraqi cities under consideration. It is clear that, for all the cities under consideration, the daily AQI is mostly “Moderate” and to a less extent “Unhealthy for sensitive groups”. However, there are 53 days for Al-Muthanna (mainly due to PM10) and 58 days for Baghdad (due to PM2.5 alone) in which the AQI is “Unhealthy”. Moreover, there are another 53 days for Al-Muthanna in which the AQI is “Hazardus”. So, the air quality in Al-Muthanna and Baghdad can be considered lower than that in other cities. Indeed, this is attributed to dust storms in Al-Muthanna and high population of Baghdad city and consequently higher air pollutants emissions due to their industrial, transportation and electric generation activities. AirQ+ software was used to assess public health consequences of long term exposure to PM2.5 in terms of relative risk (RR). RR of acute lower respiratory disease, chronic obstructive pulmonary, mortality by lung cancer, ischemic heart disease, mortality by stroke for the five cities were assessed. RR of mortality by lung cancer due to exposure to PM2.5 in Baghdad is the highest among the cities under consideration. RRLC= 1.25 (95% CI = 1.14 – 1.4).
Radiation Control of Halogen Lamps Falling on Double Pass Solar Air Heater
Authors: Ali Shrooq Jomaa , Jalil Jalal M , Al-Karim Shereen F Abd
Published: March 2021

This paper studies the control of radiation on double-pass solar air heaters with porous media in the lower channel. The intensity of radiations was controlled in two ways potentiometer and mobile via the Bluetooth by designing, building, and implementing a light control system which consists of a power supply, transformer, two Arduino microcontroller (which programmed with C++ language), bridge rectifier, resistances, two optocouplers, TRAIC, Bluetooth model, toggle switch and LCD Display. The results showed the inverse relationship between the solar radiation and the resistance, the maximum solar radiation obtained from this work reached 786 W/m2when the resistance is 1.15 kΩ, while the minimum solar radiation is 158.6 W/m2when the resistance is 6.21 kΩ. The output power increases with increasing solar radiation, which means the maximum output power reaches 2567 W at the maximum solar radiation.
A New Smart Approach for Best Location Determination Based on Internet of Things
Authors: Aziz Hadeel Hussein , Abdullah Mahmood Zaki
Published: March 2021

Finding the best location among several alternatives require more effort, time, and devices in the usual cases, especially if these locations in another city or governorate. This study pursuit using a smart approach to select the best new primary school site with an accurate result in a short time and low cost. The presented approach utilizes a smartphone as an internet of things (IoT) device that has an internal Global Positioning System (GPS) unit to collect and send the location (GPS coordinates) via Google maps application to urban planners (decision-makers) to give their opinion in each site sent to them after making a spatial analysis for these site using the Arc GIS program to assess every advised site with each criterion. Then, the fuzzy TOPSIS method aggregates urban planners’ opinions to determine the more suitable site for a new primary school. The Fuzzy TOPSIS method was implemented using python code to reduce the time required for manual computation. All the Fuzzy TOPSIS steps executed time does not exceed 1 minute, and it just needs to enter the number of (criteria, decision-makers, and alternative sites). The importance weight of the criteria for each decision-maker and the ratings of alternative sites by the decision-makers’ chosen criteria. So with this smart approach, with a few hours, we can find a more fitting new site, although it took more than a week in the normal way.
Performance Evaluation of Eco-Friendly Ultra-High-Performance Concrete Incorporated with Waste Glass-A Review
Authors: Esmaeili Jamshid , AL-Mwanes Ammar Oudah
Published: March 2021

The ultra-high-performance glass concrete (UHPGC) is an advanced UHPC innovative pioneer in sustainable concrete technology. UHPGC technology can provide environmental benefits through the use of post-consumer glass. Economic benefits through the decrease in the amount of landfilled materials are undesirable as they are neither biodegradable nor environmentally friendly and could reduce the costs for UHPC. Compressive strength greater than 150 MPa and mini-slump spread diameter bigger than 250 mm can be achieved, depending on the UHPGC composition and curing temperature. The glass powder (GP) milled to the micro-scale is subjected to low pozzolanic reaction and works as a catalyst speeding clinker dissolution forming calcium silicate hydrate (C-S-H). These reactions have a good positive influence on both UHPC’s mechanical and microstructural properties. This paper overviews previous studies carried out as partial or full replacement of sand or quartz sand (QS), quartz powder (QP), and silica fume (SF) by the use of milled waste glass (WG) in UHPC mixture. Nowadays, the sustainability of the construction sector must be a priority for the scientific community. So, the development of the used materials and methods to extend the lifetime of concrete structures is mandatory.